Add rust-analyzer-span server feature equivalent to the ID server

17 files changed, 1158 insertions, 557 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 2cb26d0c597..aeb7444aa30 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1277,6 +1277,7 @@ dependencies = [
 name = "proc-macro-srv"
 version = "0.0.0"
 dependencies = [
+ "base-db",
  "expect-test",
  "libloading",
  "mbe",
@@ -1285,6 +1286,7 @@ dependencies = [
  "paths",
  "proc-macro-api",
  "proc-macro-test",
+ "span",
  "stdx",
  "tt",
 ]
diff --git a/crates/proc-macro-api/src/lib.rs b/crates/proc-macro-api/src/lib.rs
index a5d4cfeb275..be68f6eff66 100644
--- a/crates/proc-macro-api/src/lib.rs
+++ b/crates/proc-macro-api/src/lib.rs
@@ -20,7 +20,10 @@ use triomphe::Arc;
 use serde::{Deserialize, Serialize};
 
 use crate::{
-    msg::{ExpandMacro, ExpnGlobals, FlatTree, PanicMessage, HAS_GLOBAL_SPANS},
+    msg::{
+        flat::serialize_span_data_index_map, ExpandMacro, ExpnGlobals, FlatTree, PanicMessage,
+        HAS_GLOBAL_SPANS, RUST_ANALYZER_SPAN_SUPPORT,
+    },
     process::ProcMacroProcessSrv,
 };
 
@@ -166,6 +169,11 @@ impl ProcMacro {
                 call_site,
                 mixed_site,
             },
+            span_data_table: if version >= RUST_ANALYZER_SPAN_SUPPORT {
+                serialize_span_data_index_map(&span_data_table)
+            } else {
+                Vec::new()
+            },
         };
 
         let response = self
@@ -178,9 +186,7 @@ impl ProcMacro {
             msg::Response::ExpandMacro(it) => {
                 Ok(it.map(|tree| FlatTree::to_subtree_resolved(tree, version, &span_data_table)))
             }
-            msg::Response::ListMacros(..) | msg::Response::ApiVersionCheck(..) => {
-                Err(ServerError { message: "unexpected response".to_string(), io: None })
-            }
+            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
         }
     }
 }
diff --git a/crates/proc-macro-api/src/msg.rs b/crates/proc-macro-api/src/msg.rs
index 18fd9ed7284..7ef6d5b0556 100644
--- a/crates/proc-macro-api/src/msg.rs
+++ b/crates/proc-macro-api/src/msg.rs
@@ -10,28 +10,42 @@ use serde::{de::DeserializeOwned, Deserialize, Serialize};
 
 use crate::ProcMacroKind;
 
-pub use crate::msg::flat::{FlatTree, TokenId};
+pub use crate::msg::flat::{
+    deserialize_span_data_index_map, serialize_span_data_index_map, FlatTree, SpanDataIndexMap,
+    TokenId,
+};
 
 // The versions of the server protocol
 pub const NO_VERSION_CHECK_VERSION: u32 = 0;
 pub const VERSION_CHECK_VERSION: u32 = 1;
 pub const ENCODE_CLOSE_SPAN_VERSION: u32 = 2;
 pub const HAS_GLOBAL_SPANS: u32 = 3;
+pub const RUST_ANALYZER_SPAN_SUPPORT: u32 = 4;
 
-pub const CURRENT_API_VERSION: u32 = HAS_GLOBAL_SPANS;
+pub const CURRENT_API_VERSION: u32 = RUST_ANALYZER_SPAN_SUPPORT;
 
 #[derive(Debug, Serialize, Deserialize)]
 pub enum Request {
     ListMacros { dylib_path: PathBuf },
     ExpandMacro(ExpandMacro),
+    SetSpanMode(SpanMode),
     ApiVersionCheck {},
 }
 
+#[derive(Copy, Clone, Default, Debug, Serialize, Deserialize)]
+pub enum SpanMode {
+    #[default]
+    Id,
+    RustAnalyzer,
+}
+
 #[derive(Debug, Serialize, Deserialize)]
 pub enum Response {
     ListMacros(Result<Vec<(String, ProcMacroKind)>, String>),
     ExpandMacro(Result<FlatTree, PanicMessage>),
+    ExpandMacroSpans(Result<(FlatTree, Vec<u32>), PanicMessage>),
     ApiVersionCheck(u32),
+    SetSpanMode(SpanMode),
 }
 
 #[derive(Debug, Serialize, Deserialize)]
@@ -64,9 +78,12 @@ pub struct ExpandMacro {
     #[serde(skip_serializing_if = "ExpnGlobals::skip_serializing_if")]
     #[serde(default)]
     pub has_global_spans: ExpnGlobals,
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    #[serde(default)]
+    pub span_data_table: Vec<u32>,
 }
 
-#[derive(Default, Debug, Serialize, Deserialize)]
+#[derive(Copy, Clone, Default, Debug, Serialize, Deserialize)]
 pub struct ExpnGlobals {
     #[serde(skip_serializing)]
     #[serde(default)]
@@ -241,6 +258,7 @@ mod tests {
                 call_site: 0,
                 mixed_site: 0,
             },
+            span_data_table: Vec::new(),
         };
 
         let json = serde_json::to_string(&task).unwrap();
diff --git a/crates/proc-macro-api/src/msg/flat.rs b/crates/proc-macro-api/src/msg/flat.rs
index a12581ac138..8dfaba52625 100644
--- a/crates/proc-macro-api/src/msg/flat.rs
+++ b/crates/proc-macro-api/src/msg/flat.rs
@@ -38,12 +38,45 @@
 use std::collections::{HashMap, VecDeque};
 
 use indexmap::IndexSet;
+use la_arena::RawIdx;
 use serde::{Deserialize, Serialize};
-use span::Span;
+use span::{ErasedFileAstId, FileId, Span, SpanAnchor, SyntaxContextId};
+use text_size::TextRange;
 
 use crate::msg::ENCODE_CLOSE_SPAN_VERSION;
 
-type SpanIndexMap = IndexSet<Span>;
+pub type SpanDataIndexMap = IndexSet<Span>;
+
+pub fn serialize_span_data_index_map(map: &SpanDataIndexMap) -> Vec<u32> {
+    map.iter()
+        .flat_map(|span| {
+            [
+                span.anchor.file_id.index(),
+                span.anchor.ast_id.into_raw().into_u32(),
+                span.range.start().into(),
+                span.range.end().into(),
+                span.ctx.into_u32(),
+            ]
+        })
+        .collect()
+}
+
+pub fn deserialize_span_data_index_map(map: &[u32]) -> SpanDataIndexMap {
+    debug_assert!(map.len() % 5 == 0);
+    map.chunks_exact(5)
+        .map(|span| {
+            let &[file_id, ast_id, start, end, e] = span else { unreachable!() };
+            Span {
+                anchor: SpanAnchor {
+                    file_id: FileId::from_raw(file_id),
+                    ast_id: ErasedFileAstId::from_raw(RawIdx::from_u32(ast_id)),
+                },
+                range: TextRange::new(start.into(), end.into()),
+                ctx: SyntaxContextId::from_u32(e),
+            }
+        })
+        .collect()
+}
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 pub struct TokenId(pub u32);
@@ -93,7 +126,7 @@ impl FlatTree {
     pub fn new(
         subtree: &tt::Subtree<Span>,
         version: u32,
-        span_data_table: &mut SpanIndexMap,
+        span_data_table: &mut SpanDataIndexMap,
     ) -> FlatTree {
         let mut w = Writer {
             string_table: HashMap::new(),
@@ -155,7 +188,7 @@ impl FlatTree {
     pub fn to_subtree_resolved(
         self,
         version: u32,
-        span_data_table: &SpanIndexMap,
+        span_data_table: &SpanDataIndexMap,
     ) -> tt::Subtree<Span> {
         Reader {
             subtree: if version >= ENCODE_CLOSE_SPAN_VERSION {
diff --git a/crates/proc-macro-api/src/process.rs b/crates/proc-macro-api/src/process.rs
index 9a20fa63ed7..ed55ca5bd53 100644
--- a/crates/proc-macro-api/src/process.rs
+++ b/crates/proc-macro-api/src/process.rs
@@ -9,7 +9,7 @@ use paths::{AbsPath, AbsPathBuf};
 use stdx::JodChild;
 
 use crate::{
-    msg::{Message, Request, Response, CURRENT_API_VERSION},
+    msg::{Message, Request, Response, SpanMode, CURRENT_API_VERSION, RUST_ANALYZER_SPAN_SUPPORT},
     ProcMacroKind, ServerError,
 };
 
@@ -19,6 +19,7 @@ pub(crate) struct ProcMacroProcessSrv {
     stdin: ChildStdin,
     stdout: BufReader<ChildStdout>,
     version: u32,
+    mode: SpanMode,
 }
 
 impl ProcMacroProcessSrv {
@@ -27,7 +28,13 @@ impl ProcMacroProcessSrv {
             let mut process = Process::run(process_path.clone(), null_stderr)?;
             let (stdin, stdout) = process.stdio().expect("couldn't access child stdio");
 
-            io::Result::Ok(ProcMacroProcessSrv { _process: process, stdin, stdout, version: 0 })
+            io::Result::Ok(ProcMacroProcessSrv {
+                _process: process,
+                stdin,
+                stdout,
+                version: 0,
+                mode: SpanMode::Id,
+            })
         };
         let mut srv = create_srv(true)?;
         tracing::info!("sending version check");
@@ -43,6 +50,11 @@ impl ProcMacroProcessSrv {
                 tracing::info!("got version {v}");
                 srv = create_srv(false)?;
                 srv.version = v;
+                if srv.version > RUST_ANALYZER_SPAN_SUPPORT {
+                    if let Ok(mode) = srv.enable_rust_analyzer_spans() {
+                        srv.mode = mode;
+                    }
+                }
                 Ok(srv)
             }
             Err(e) => {
@@ -62,9 +74,17 @@ impl ProcMacroProcessSrv {
 
         match response {
             Response::ApiVersionCheck(version) => Ok(version),
-            Response::ExpandMacro { .. } | Response::ListMacros { .. } => {
-                Err(ServerError { message: "unexpected response".to_string(), io: None })
-            }
+            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
+        }
+    }
+
+    fn enable_rust_analyzer_spans(&mut self) -> Result<SpanMode, ServerError> {
+        let request = Request::SetSpanMode(crate::msg::SpanMode::RustAnalyzer);
+        let response = self.send_task(request)?;
+
+        match response {
+            Response::SetSpanMode(span_mode) => Ok(span_mode),
+            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
         }
     }
 
@@ -78,9 +98,7 @@ impl ProcMacroProcessSrv {
 
         match response {
             Response::ListMacros(it) => Ok(it),
-            Response::ExpandMacro { .. } | Response::ApiVersionCheck { .. } => {
-                Err(ServerError { message: "unexpected response".to_string(), io: None })
-            }
+            _ => Err(ServerError { message: "unexpected response".to_string(), io: None }),
         }
     }
 
diff --git a/crates/proc-macro-srv-cli/src/main.rs b/crates/proc-macro-srv-cli/src/main.rs
index 50ce586fc42..f4e88ed437e 100644
--- a/crates/proc-macro-srv-cli/src/main.rs
+++ b/crates/proc-macro-srv-cli/src/main.rs
@@ -39,10 +39,17 @@ fn run() -> io::Result<()> {
             msg::Request::ListMacros { dylib_path } => {
                 msg::Response::ListMacros(srv.list_macros(&dylib_path))
             }
-            msg::Request::ExpandMacro(task) => msg::Response::ExpandMacro(srv.expand(task)),
+            msg::Request::ExpandMacro(task) => match srv.span_mode() {
+                msg::SpanMode::Id => msg::Response::ExpandMacro(srv.expand(task).map(|(it, _)| it)),
+                msg::SpanMode::RustAnalyzer => msg::Response::ExpandMacroSpans(srv.expand(task)),
+            },
             msg::Request::ApiVersionCheck {} => {
                 msg::Response::ApiVersionCheck(proc_macro_api::msg::CURRENT_API_VERSION)
             }
+            msg::Request::SetSpanMode(span_mode) => {
+                srv.set_span_mode(span_mode);
+                msg::Response::SetSpanMode(span_mode)
+            }
         };
         write_response(res)?
     }
diff --git a/crates/proc-macro-srv/Cargo.toml b/crates/proc-macro-srv/Cargo.toml
index 99993f16e27..3bcc6e12cb1 100644
--- a/crates/proc-macro-srv/Cargo.toml
+++ b/crates/proc-macro-srv/Cargo.toml
@@ -26,6 +26,8 @@ stdx.workspace = true
 tt.workspace = true
 mbe.workspace = true
 paths.workspace = true
+base-db.workspace = true
+span.workspace = true
 proc-macro-api.workspace = true
 
 [dev-dependencies]
diff --git a/crates/proc-macro-srv/src/dylib.rs b/crates/proc-macro-srv/src/dylib.rs
index f20e6832f6e..52b4cced5f5 100644
--- a/crates/proc-macro-srv/src/dylib.rs
+++ b/crates/proc-macro-srv/src/dylib.rs
@@ -11,7 +11,10 @@ use libloading::Library;
 use memmap2::Mmap;
 use object::Object;
 use paths::AbsPath;
-use proc_macro_api::{msg::TokenId, read_dylib_info, ProcMacroKind};
+use proc_macro::bridge;
+use proc_macro_api::{read_dylib_info, ProcMacroKind};
+
+use crate::ProcMacroSrvSpan;
 
 const NEW_REGISTRAR_SYMBOL: &str = "_rustc_proc_macro_decls_";
 
@@ -147,15 +150,18 @@ impl Expander {
         Ok(Expander { inner: library })
     }
 
-    pub fn expand(
+    pub fn expand<S: ProcMacroSrvSpan>(
         &self,
         macro_name: &str,
-        macro_body: &crate::tt::Subtree,
-        attributes: Option<&crate::tt::Subtree>,
-        def_site: TokenId,
-        call_site: TokenId,
-        mixed_site: TokenId,
-    ) -> Result<crate::tt::Subtree, String> {
+        macro_body: tt::Subtree<S>,
+        attributes: Option<tt::Subtree<S>>,
+        def_site: S,
+        call_site: S,
+        mixed_site: S,
+    ) -> Result<tt::Subtree<S>, String>
+    where
+        <S::Server as bridge::server::Types>::TokenStream: Default,
+    {
         let result = self
             .inner
             .proc_macros
diff --git a/crates/proc-macro-srv/src/lib.rs b/crates/proc-macro-srv/src/lib.rs
index 56529f71d85..3f62ded24cf 100644
--- a/crates/proc-macro-srv/src/lib.rs
+++ b/crates/proc-macro-srv/src/lib.rs
@@ -32,36 +32,60 @@ use std::{
 };
 
 use proc_macro_api::{
-    msg::{self, ExpnGlobals, TokenId, CURRENT_API_VERSION},
+    msg::{
+        self, deserialize_span_data_index_map, serialize_span_data_index_map, ExpnGlobals,
+        SpanDataIndexMap, SpanMode, TokenId, CURRENT_API_VERSION,
+    },
     ProcMacroKind,
 };
+use span::Span;
 
-mod tt {
-    pub use proc_macro_api::msg::TokenId;
+use crate::server::TokenStream;
 
-    pub use ::tt::*;
+// see `build.rs`
+include!(concat!(env!("OUT_DIR"), "/rustc_version.rs"));
 
-    pub type Subtree = ::tt::Subtree<TokenId>;
-    pub type TokenTree = ::tt::TokenTree<TokenId>;
-    pub type Delimiter = ::tt::Delimiter<TokenId>;
-    pub type Leaf = ::tt::Leaf<TokenId>;
-    pub type Literal = ::tt::Literal<TokenId>;
-    pub type Punct = ::tt::Punct<TokenId>;
-    pub type Ident = ::tt::Ident<TokenId>;
+trait ProcMacroSrvSpan: tt::Span {
+    type Server: proc_macro::bridge::server::Server<TokenStream = TokenStream<Self>>;
+    fn make_server(call_site: Self, def_site: Self, mixed_site: Self) -> Self::Server;
 }
 
-// see `build.rs`
-include!(concat!(env!("OUT_DIR"), "/rustc_version.rs"));
+impl ProcMacroSrvSpan for TokenId {
+    type Server = server::token_id::TokenIdServer;
+
+    fn make_server(call_site: Self, def_site: Self, mixed_site: Self) -> Self::Server {
+        Self::Server { interner: &server::SYMBOL_INTERNER, call_site, def_site, mixed_site }
+    }
+}
+impl ProcMacroSrvSpan for Span {
+    type Server = server::rust_analyzer_span::RaSpanServer;
+    fn make_server(call_site: Self, def_site: Self, mixed_site: Self) -> Self::Server {
+        Self::Server { interner: &server::SYMBOL_INTERNER, call_site, def_site, mixed_site }
+    }
+}
 
 #[derive(Default)]
 pub struct ProcMacroSrv {
     expanders: HashMap<(PathBuf, SystemTime), dylib::Expander>,
+    span_mode: SpanMode,
 }
 
 const EXPANDER_STACK_SIZE: usize = 8 * 1024 * 1024;
 
 impl ProcMacroSrv {
-    pub fn expand(&mut self, task: msg::ExpandMacro) -> Result<msg::FlatTree, msg::PanicMessage> {
+    pub fn set_span_mode(&mut self, span_mode: SpanMode) {
+        self.span_mode = span_mode;
+    }
+
+    pub fn span_mode(&self) -> SpanMode {
+        self.span_mode
+    }
+
+    pub fn expand(
+        &mut self,
+        task: msg::ExpandMacro,
+    ) -> Result<(msg::FlatTree, Vec<u32>), msg::PanicMessage> {
+        let span_mode = self.span_mode;
         let expander = self.expander(task.lib.as_ref()).map_err(|err| {
             debug_assert!(false, "should list macros before asking to expand");
             msg::PanicMessage(format!("failed to load macro: {err}"))
@@ -71,10 +95,10 @@ impl ProcMacroSrv {
         for (k, v) in &task.env {
             env::set_var(k, v);
         }
-        let prev_working_dir = match task.current_dir {
+        let prev_working_dir = match &task.current_dir {
             Some(dir) => {
                 let prev_working_dir = std::env::current_dir().ok();
-                if let Err(err) = std::env::set_current_dir(&dir) {
+                if let Err(err) = std::env::set_current_dir(dir) {
                     eprintln!("Failed to set the current working dir to {dir}. Error: {err:?}")
                 }
                 prev_working_dir
@@ -83,38 +107,15 @@ impl ProcMacroSrv {
         };
 
         let ExpnGlobals { def_site, call_site, mixed_site, .. } = task.has_global_spans;
-        let def_site = TokenId(def_site as u32);
-        let call_site = TokenId(call_site as u32);
-        let mixed_site = TokenId(mixed_site as u32);
-
-        let macro_body = task.macro_body.to_subtree_unresolved(CURRENT_API_VERSION);
-        let attributes = task.attributes.map(|it| it.to_subtree_unresolved(CURRENT_API_VERSION));
-        let result = thread::scope(|s| {
-            let thread = thread::Builder::new()
-                .stack_size(EXPANDER_STACK_SIZE)
-                .name(task.macro_name.clone())
-                .spawn_scoped(s, || {
-                    expander
-                        .expand(
-                            &task.macro_name,
-                            &macro_body,
-                            attributes.as_ref(),
-                            def_site,
-                            call_site,
-                            mixed_site,
-                        )
-                        .map(|it| msg::FlatTree::new_raw(&it, CURRENT_API_VERSION))
-                });
-            let res = match thread {
-                Ok(handle) => handle.join(),
-                Err(e) => std::panic::resume_unwind(Box::new(e)),
-            };
-
-            match res {
-                Ok(res) => res,
-                Err(e) => std::panic::resume_unwind(e),
+
+        let result = match span_mode {
+            SpanMode::Id => {
+                expand_id(task, expander, def_site, call_site, mixed_site).map(|it| (it, vec![]))
             }
-        });
+            SpanMode::RustAnalyzer => {
+                expand_ra_span(task, expander, def_site, call_site, mixed_site)
+            }
+        };
 
         prev_env.rollback();
 
@@ -155,6 +156,98 @@ impl ProcMacroSrv {
     }
 }
 
+fn expand_id(
+    task: msg::ExpandMacro,
+    expander: &dylib::Expander,
+    def_site: usize,
+    call_site: usize,
+    mixed_site: usize,
+) -> Result<msg::FlatTree, String> {
+    let def_site = TokenId(def_site as u32);
+    let call_site = TokenId(call_site as u32);
+    let mixed_site = TokenId(mixed_site as u32);
+
+    let macro_body = task.macro_body.to_subtree_unresolved(CURRENT_API_VERSION);
+    let attributes = task.attributes.map(|it| it.to_subtree_unresolved(CURRENT_API_VERSION));
+    let result = thread::scope(|s| {
+        let thread = thread::Builder::new()
+            .stack_size(EXPANDER_STACK_SIZE)
+            .name(task.macro_name.clone())
+            .spawn_scoped(s, || {
+                expander
+                    .expand(
+                        &task.macro_name,
+                        macro_body,
+                        attributes,
+                        def_site,
+                        call_site,
+                        mixed_site,
+                    )
+                    .map(|it| msg::FlatTree::new_raw(&it, CURRENT_API_VERSION))
+            });
+        let res = match thread {
+            Ok(handle) => handle.join(),
+            Err(e) => std::panic::resume_unwind(Box::new(e)),
+        };
+
+        match res {
+            Ok(res) => res,
+            Err(e) => std::panic::resume_unwind(e),
+        }
+    });
+    result
+}
+
+fn expand_ra_span(
+    task: msg::ExpandMacro,
+    expander: &dylib::Expander,
+    def_site: usize,
+    call_site: usize,
+    mixed_site: usize,
+) -> Result<(msg::FlatTree, Vec<u32>), String> {
+    let mut span_data_table = deserialize_span_data_index_map(&task.span_data_table);
+
+    let def_site = span_data_table[def_site];
+    let call_site = span_data_table[call_site];
+    let mixed_site = span_data_table[mixed_site];
+
+    let macro_body = task.macro_body.to_subtree_resolved(CURRENT_API_VERSION, &span_data_table);
+    let attributes =
+        task.attributes.map(|it| it.to_subtree_resolved(CURRENT_API_VERSION, &span_data_table));
+    let result = thread::scope(|s| {
+        let thread = thread::Builder::new()
+            .stack_size(EXPANDER_STACK_SIZE)
+            .name(task.macro_name.clone())
+            .spawn_scoped(s, || {
+                expander
+                    .expand(
+                        &task.macro_name,
+                        macro_body,
+                        attributes,
+                        def_site,
+                        call_site,
+                        mixed_site,
+                    )
+                    .map(|it| {
+                        (
+                            msg::FlatTree::new(&it, CURRENT_API_VERSION, &mut span_data_table),
+                            serialize_span_data_index_map(&span_data_table),
+                        )
+                    })
+            });
+        let res = match thread {
+            Ok(handle) => handle.join(),
+            Err(e) => std::panic::resume_unwind(Box::new(e)),
+        };
+
+        match res {
+            Ok(res) => res,
+            Err(e) => std::panic::resume_unwind(e),
+        }
+    });
+    result
+}
+
 pub struct PanicMessage {
     message: Option<String>,
 }
diff --git a/crates/proc-macro-srv/src/proc_macros.rs b/crates/proc-macro-srv/src/proc_macros.rs
index 716b85d096d..a75c0e619bc 100644
--- a/crates/proc-macro-srv/src/proc_macros.rs
+++ b/crates/proc-macro-srv/src/proc_macros.rs
@@ -2,9 +2,9 @@
 
 use libloading::Library;
 use proc_macro::bridge;
-use proc_macro_api::{msg::TokenId, ProcMacroKind, RustCInfo};
+use proc_macro_api::{ProcMacroKind, RustCInfo};
 
-use crate::{dylib::LoadProcMacroDylibError, server::SYMBOL_INTERNER, tt};
+use crate::{dylib::LoadProcMacroDylibError, ProcMacroSrvSpan};
 
 pub(crate) struct ProcMacros {
     exported_macros: Vec<bridge::client::ProcMacro>,
@@ -40,19 +40,19 @@ impl ProcMacros {
         Err(LoadProcMacroDylibError::AbiMismatch(info.version_string))
     }
 
-    pub(crate) fn expand(
+    pub(crate) fn expand<S: ProcMacroSrvSpan>(
         &self,
         macro_name: &str,
-        macro_body: &tt::Subtree,
-        attributes: Option<&tt::Subtree>,
-        def_site: TokenId,
-        call_site: TokenId,
-        mixed_site: TokenId,
-    ) -> Result<tt::Subtree, crate::PanicMessage> {
-        let parsed_body = crate::server::TokenStream::with_subtree(macro_body.clone());
+        macro_body: tt::Subtree<S>,
+        attributes: Option<tt::Subtree<S>>,
+        def_site: S,
+        call_site: S,
+        mixed_site: S,
+    ) -> Result<tt::Subtree<S>, crate::PanicMessage> {
+        let parsed_body = crate::server::TokenStream::with_subtree(macro_body);
 
-        let parsed_attributes = attributes.map_or(crate::server::TokenStream::new(), |attr| {
-            crate::server::TokenStream::with_subtree(attr.clone())
+        let parsed_attributes = attributes.map_or_else(crate::server::TokenStream::new, |attr| {
+            crate::server::TokenStream::with_subtree(attr)
         });
 
         for proc_macro in &self.exported_macros {
@@ -62,12 +62,7 @@ impl ProcMacros {
                 {
                     let res = client.run(
                         &bridge::server::SameThread,
-                        crate::server::RustAnalyzer {
-                            interner: &SYMBOL_INTERNER,
-                            call_site,
-                            def_site,
-                            mixed_site,
-                        },
+                        S::make_server(call_site, def_site, mixed_site),
                         parsed_body,
                         false,
                     );
@@ -78,12 +73,7 @@ impl ProcMacros {
                 bridge::client::ProcMacro::Bang { name, client } if *name == macro_name => {
                     let res = client.run(
                         &bridge::server::SameThread,
-                        crate::server::RustAnalyzer {
-                            interner: &SYMBOL_INTERNER,
-                            call_site,
-                            def_site,
-                            mixed_site,
-                        },
+                        S::make_server(call_site, def_site, mixed_site),
                         parsed_body,
                         false,
                     );
@@ -94,13 +84,7 @@ impl ProcMacros {
                 bridge::client::ProcMacro::Attr { name, client } if *name == macro_name => {
                     let res = client.run(
                         &bridge::server::SameThread,
-                        crate::server::RustAnalyzer {
-                            interner: &SYMBOL_INTERNER,
-
-                            call_site,
-                            def_site,
-                            mixed_site,
-                        },
+                        S::make_server(call_site, def_site, mixed_site),
                         parsed_attributes,
                         parsed_body,
                         false,
diff --git a/crates/proc-macro-srv/src/server.rs b/crates/proc-macro-srv/src/server.rs
index 917d8a6e26a..1854322ddb5 100644
--- a/crates/proc-macro-srv/src/server.rs
+++ b/crates/proc-macro-srv/src/server.rs
@@ -8,226 +8,18 @@
 //!
 //! FIXME: No span and source file information is implemented yet
 
-use proc_macro::bridge::{self, server};
+use proc_macro::bridge;
 
 mod token_stream;
-use proc_macro_api::msg::TokenId;
 pub use token_stream::TokenStream;
-use token_stream::TokenStreamBuilder;
 
+pub mod token_id;
+pub mod rust_analyzer_span;
 mod symbol;
 pub use symbol::*;
+use tt::Spacing;
 
-use std::{
-    iter,
-    ops::{Bound, Range},
-};
-
-use crate::tt;
-
-type Group = tt::Subtree;
-type TokenTree = tt::TokenTree;
-#[allow(unused)]
-type Punct = tt::Punct;
-type Spacing = tt::Spacing;
-#[allow(unused)]
-type Literal = tt::Literal;
-type Span = tt::TokenId;
-
-#[derive(Clone)]
-pub struct SourceFile {
-    // FIXME stub
-}
-
-pub struct FreeFunctions;
-
-pub struct RustAnalyzer {
-    // FIXME: store span information here.
-    pub(crate) interner: SymbolInternerRef,
-    pub call_site: TokenId,
-    pub def_site: TokenId,
-    pub mixed_site: TokenId,
-}
-
-impl server::Types for RustAnalyzer {
-    type FreeFunctions = FreeFunctions;
-    type TokenStream = TokenStream;
-    type SourceFile = SourceFile;
-    type Span = Span;
-    type Symbol = Symbol;
-}
-
-impl server::FreeFunctions for RustAnalyzer {
-    fn injected_env_var(&mut self, _var: &str) -> Option<String> {
-        None
-    }
-
-    fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {
-        // FIXME: track env var accesses
-        // https://github.com/rust-lang/rust/pull/71858
-    }
-    fn track_path(&mut self, _path: &str) {}
-
-    fn literal_from_str(
-        &mut self,
-        s: &str,
-    ) -> Result<bridge::Literal<Self::Span, Self::Symbol>, ()> {
-        // FIXME: keep track of LitKind and Suffix
-        Ok(bridge::Literal {
-            kind: bridge::LitKind::Err,
-            symbol: Symbol::intern(self.interner, s),
-            suffix: None,
-            span: self.call_site,
-        })
-    }
-
-    fn emit_diagnostic(&mut self, _: bridge::Diagnostic<Self::Span>) {
-        // FIXME handle diagnostic
-    }
-}
-
-impl server::TokenStream for RustAnalyzer {
-    fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
-        stream.is_empty()
-    }
-    fn from_str(&mut self, src: &str) -> Self::TokenStream {
-        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
-    }
-    fn to_string(&mut self, stream: &Self::TokenStream) -> String {
-        stream.to_string()
-    }
-    fn from_token_tree(
-        &mut self,
-        tree: bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>,
-    ) -> Self::TokenStream {
-        match tree {
-            bridge::TokenTree::Group(group) => {
-                let group = Group {
-                    delimiter: delim_to_internal(group.delimiter, group.span),
-                    token_trees: match group.stream {
-                        Some(stream) => stream.into_iter().collect(),
-                        None => Vec::new(),
-                    },
-                };
-                let tree = TokenTree::from(group);
-                Self::TokenStream::from_iter(iter::once(tree))
-            }
-
-            bridge::TokenTree::Ident(ident) => {
-                let text = ident.sym.text(self.interner);
-                let text =
-                    if ident.is_raw { ::tt::SmolStr::from_iter(["r#", &text]) } else { text };
-                let ident: tt::Ident = tt::Ident { text, span: ident.span };
-                let leaf = tt::Leaf::from(ident);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(iter::once(tree))
-            }
-
-            bridge::TokenTree::Literal(literal) => {
-                let literal = LiteralFormatter(literal);
-                let text = literal.with_stringify_parts(self.interner, |parts| {
-                    ::tt::SmolStr::from_iter(parts.iter().copied())
-                });
-
-                let literal = tt::Literal { text, span: literal.0.span };
-                let leaf = tt::Leaf::from(literal);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(iter::once(tree))
-            }
-
-            bridge::TokenTree::Punct(p) => {
-                let punct = tt::Punct {
-                    char: p.ch as char,
-                    spacing: if p.joint { Spacing::Joint } else { Spacing::Alone },
-                    span: p.span,
-                };
-                let leaf = tt::Leaf::from(punct);
-                let tree = TokenTree::from(leaf);
-                Self::TokenStream::from_iter(iter::once(tree))
-            }
-        }
-    }
-
-    fn expand_expr(&mut self, self_: &Self::TokenStream) -> Result<Self::TokenStream, ()> {
-        Ok(self_.clone())
-    }
-
-    fn concat_trees(
-        &mut self,
-        base: Option<Self::TokenStream>,
-        trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
-    ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
-        if let Some(base) = base {
-            builder.push(base);
-        }
-        for tree in trees {
-            builder.push(self.from_token_tree(tree));
-        }
-        builder.build()
-    }
-
-    fn concat_streams(
-        &mut self,
-        base: Option<Self::TokenStream>,
-        streams: Vec<Self::TokenStream>,
-    ) -> Self::TokenStream {
-        let mut builder = TokenStreamBuilder::new();
-        if let Some(base) = base {
-            builder.push(base);
-        }
-        for stream in streams {
-            builder.push(stream);
-        }
-        builder.build()
-    }
-
-    fn into_trees(
-        &mut self,
-        stream: Self::TokenStream,
-    ) -> Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>> {
-        stream
-            .into_iter()
-            .map(|tree| match tree {
-                tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
-                    bridge::TokenTree::Ident(bridge::Ident {
-                        sym: Symbol::intern(self.interner, ident.text.trim_start_matches("r#")),
-                        is_raw: ident.text.starts_with("r#"),
-                        span: ident.span,
-                    })
-                }
-                tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) => {
-                    bridge::TokenTree::Literal(bridge::Literal {
-                        // FIXME: handle literal kinds
-                        kind: bridge::LitKind::Err,
-                        symbol: Symbol::intern(self.interner, &lit.text),
-                        // FIXME: handle suffixes
-                        suffix: None,
-                        span: lit.span,
-                    })
-                }
-                tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => {
-                    bridge::TokenTree::Punct(bridge::Punct {
-                        ch: punct.char as u8,
-                        joint: punct.spacing == Spacing::Joint,
-                        span: punct.span,
-                    })
-                }
-                tt::TokenTree::Subtree(subtree) => bridge::TokenTree::Group(bridge::Group {
-                    delimiter: delim_to_external(subtree.delimiter),
-                    stream: if subtree.token_trees.is_empty() {
-                        None
-                    } else {
-                        Some(subtree.token_trees.into_iter().collect())
-                    },
-                    span: bridge::DelimSpan::from_single(subtree.delimiter.open),
-                }),
-            })
-            .collect()
-    }
-}
-
-fn delim_to_internal(d: proc_macro::Delimiter, span: bridge::DelimSpan<Span>) -> tt::Delimiter {
+fn delim_to_internal<S>(d: proc_macro::Delimiter, span: bridge::DelimSpan<S>) -> tt::Delimiter<S> {
     let kind = match d {
         proc_macro::Delimiter::Parenthesis => tt::DelimiterKind::Parenthesis,
         proc_macro::Delimiter::Brace => tt::DelimiterKind::Brace,
@@ -237,7 +29,7 @@ fn delim_to_internal(d: proc_macro::Delimiter, span: bridge::DelimSpan<Span>) ->
     tt::Delimiter { open: span.open, close: span.close, kind }
 }
 
-fn delim_to_external(d: tt::Delimiter) -> proc_macro::Delimiter {
+fn delim_to_external<S>(d: tt::Delimiter<S>) -> proc_macro::Delimiter {
     match d.kind {
         tt::DelimiterKind::Parenthesis => proc_macro::Delimiter::Parenthesis,
         tt::DelimiterKind::Brace => proc_macro::Delimiter::Brace,
@@ -262,121 +54,9 @@ fn spacing_to_external(spacing: Spacing) -> proc_macro::Spacing {
     }
 }
 
-impl server::SourceFile for RustAnalyzer {
-    // FIXME these are all stubs
-    fn eq(&mut self, _file1: &Self::SourceFile, _file2: &Self::SourceFile) -> bool {
-        true
-    }
-    fn path(&mut self, _file: &Self::SourceFile) -> String {
-        String::new()
-    }
-    fn is_real(&mut self, _file: &Self::SourceFile) -> bool {
-        true
-    }
-}
-
-impl server::Span for RustAnalyzer {
-    fn debug(&mut self, span: Self::Span) -> String {
-        format!("{:?}", span.0)
-    }
-    fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
-        SourceFile {}
-    }
-    fn save_span(&mut self, _span: Self::Span) -> usize {
-        // FIXME stub
-        0
-    }
-    fn recover_proc_macro_span(&mut self, _id: usize) -> Self::Span {
-        // FIXME stub
-        self.call_site
-    }
-    /// Recent feature, not yet in the proc_macro
-    ///
-    /// See PR:
-    /// https://github.com/rust-lang/rust/pull/55780
-    fn source_text(&mut self, _span: Self::Span) -> Option<String> {
-        None
-    }
-
-    fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
-        // FIXME handle span
-        None
-    }
-    fn source(&mut self, span: Self::Span) -> Self::Span {
-        // FIXME handle span
-        span
-    }
-    fn byte_range(&mut self, _span: Self::Span) -> Range<usize> {
-        // FIXME handle span
-        Range { start: 0, end: 0 }
-    }
-    fn join(&mut self, first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
-        // Just return the first span again, because some macros will unwrap the result.
-        Some(first)
-    }
-    fn subspan(
-        &mut self,
-        span: Self::Span,
-        _start: Bound<usize>,
-        _end: Bound<usize>,
-    ) -> Option<Self::Span> {
-        // Just return the span again, because some macros will unwrap the result.
-        Some(span)
-    }
-    fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
-        // FIXME handle span
-        self.call_site
-    }
-
-    fn end(&mut self, _self_: Self::Span) -> Self::Span {
-        self.call_site
-    }
-
-    fn start(&mut self, _self_: Self::Span) -> Self::Span {
-        self.call_site
-    }
-
-    fn line(&mut self, _span: Self::Span) -> usize {
-        // FIXME handle line
-        0
-    }
-
-    fn column(&mut self, _span: Self::Span) -> usize {
-        // FIXME handle column
-        0
-    }
-}
-
-impl server::Symbol for RustAnalyzer {
-    fn normalize_and_validate_ident(&mut self, string: &str) -> Result<Self::Symbol, ()> {
-        // FIXME: nfc-normalize and validate idents
-        Ok(<Self as server::Server>::intern_symbol(string))
-    }
-}
-
-impl server::Server for RustAnalyzer {
-    fn globals(&mut self) -> bridge::ExpnGlobals<Self::Span> {
-        bridge::ExpnGlobals {
-            def_site: self.def_site,
-            call_site: self.call_site,
-            mixed_site: self.mixed_site,
-        }
-    }
-
-    fn intern_symbol(ident: &str) -> Self::Symbol {
-        // FIXME: should be `self.interner` once the proc-macro api allows it.
-        Symbol::intern(&SYMBOL_INTERNER, &::tt::SmolStr::from(ident))
-    }
-
-    fn with_symbol_string(symbol: &Self::Symbol, f: impl FnOnce(&str)) {
-        // FIXME: should be `self.interner` once the proc-macro api allows it.
-        f(symbol.text(&SYMBOL_INTERNER).as_str())
-    }
-}
-
-struct LiteralFormatter(bridge::Literal<tt::TokenId, Symbol>);
+struct LiteralFormatter<S>(bridge::Literal<S, Symbol>);
 
-impl LiteralFormatter {
+impl<S> LiteralFormatter<S> {
     /// Invokes the callback with a `&[&str]` consisting of each part of the
     /// literal's representation. This is done to allow the `ToString` and
     /// `Display` implementations to borrow references to symbol values, and
@@ -427,66 +107,3 @@ impl LiteralFormatter {
         f(symbol.as_str(), suffix.as_str())
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn test_ra_server_to_string() {
-        let s = TokenStream {
-            token_trees: vec![
-                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                    text: "struct".into(),
-                    span: tt::TokenId(0),
-                })),
-                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                    text: "T".into(),
-                    span: tt::TokenId(0),
-                })),
-                tt::TokenTree::Subtree(tt::Subtree {
-                    delimiter: tt::Delimiter {
-                        open: tt::TokenId(0),
-                        close: tt::TokenId(0),
-                        kind: tt::DelimiterKind::Brace,
-                    },
-                    token_trees: vec![],
-                }),
-            ],
-        };
-
-        assert_eq!(s.to_string(), "struct T {}");
-    }
-
-    #[test]
-    fn test_ra_server_from_str() {
-        let subtree_paren_a = tt::TokenTree::Subtree(tt::Subtree {
-            delimiter: tt::Delimiter {
-                open: tt::TokenId(0),
-                close: tt::TokenId(0),
-                kind: tt::DelimiterKind::Parenthesis,
-            },
-            token_trees: vec![tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                text: "a".into(),
-                span: tt::TokenId(0),
-            }))],
-        });
-
-        let t1 = TokenStream::from_str("(a)", tt::TokenId(0)).unwrap();
-        assert_eq!(t1.token_trees.len(), 1);
-        assert_eq!(t1.token_trees[0], subtree_paren_a);
-
-        let t2 = TokenStream::from_str("(a);", tt::TokenId(0)).unwrap();
-        assert_eq!(t2.token_trees.len(), 2);
-        assert_eq!(t2.token_trees[0], subtree_paren_a);
-
-        let underscore = TokenStream::from_str("_", tt::TokenId(0)).unwrap();
-        assert_eq!(
-            underscore.token_trees[0],
-            tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
-                text: "_".into(),
-                span: tt::TokenId(0),
-            }))
-        );
-    }
-}
diff --git a/crates/proc-macro-srv/src/server/rust_analyzer_span.rs b/crates/proc-macro-srv/src/server/rust_analyzer_span.rs
new file mode 100644
index 00000000000..92e1ec0a948
--- /dev/null
+++ b/crates/proc-macro-srv/src/server/rust_analyzer_span.rs
@@ -0,0 +1,327 @@
+use std::{
+    iter,
+    ops::{Bound, Range},
+};
+
+use proc_macro::bridge::{self, server};
+use span::Span;
+
+use crate::server::{
+    delim_to_external, delim_to_internal, token_stream::TokenStreamBuilder, LiteralFormatter,
+    Symbol, SymbolInternerRef, SYMBOL_INTERNER,
+};
+mod tt {
+    pub use proc_macro_api::msg::TokenId;
+
+    pub use ::tt::*;
+
+    pub type Subtree = ::tt::Subtree<super::Span>;
+    pub type TokenTree = ::tt::TokenTree<super::Span>;
+    pub type Leaf = ::tt::Leaf<super::Span>;
+    pub type Literal = ::tt::Literal<super::Span>;
+    pub type Punct = ::tt::Punct<super::Span>;
+    pub type Ident = ::tt::Ident<super::Span>;
+}
+type Group = tt::Subtree;
+type TokenTree = tt::TokenTree;
+type Punct = tt::Punct;
+type Spacing = tt::Spacing;
+type Literal = tt::Literal;
+type TokenStream = crate::server::TokenStream<Span>;
+
+#[derive(Clone)]
+pub struct SourceFile;
+pub struct FreeFunctions;
+
+pub struct RaSpanServer {
+    pub(crate) interner: SymbolInternerRef,
+    pub call_site: Span,
+    pub def_site: Span,
+    pub mixed_site: Span,
+}
+
+impl server::Types for RaSpanServer {
+    type FreeFunctions = FreeFunctions;
+    type TokenStream = TokenStream;
+    type SourceFile = SourceFile;
+    type Span = Span;
+    type Symbol = Symbol;
+}
+
+impl server::FreeFunctions for RaSpanServer {
+    fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {
+        // FIXME: track env var accesses
+        // https://github.com/rust-lang/rust/pull/71858
+    }
+    fn track_path(&mut self, _path: &str) {}
+
+    fn literal_from_str(
+        &mut self,
+        s: &str,
+    ) -> Result<bridge::Literal<Self::Span, Self::Symbol>, ()> {
+        // FIXME: keep track of LitKind and Suffix
+        Ok(bridge::Literal {
+            kind: bridge::LitKind::Err,
+            symbol: Symbol::intern(self.interner, s),
+            suffix: None,
+            span: self.call_site,
+        })
+    }
+
+    fn emit_diagnostic(&mut self, _: bridge::Diagnostic<Self::Span>) {
+        // FIXME handle diagnostic
+    }
+}
+
+impl server::TokenStream for RaSpanServer {
+    fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
+        stream.is_empty()
+    }
+    fn from_str(&mut self, src: &str) -> Self::TokenStream {
+        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+    }
+    fn to_string(&mut self, stream: &Self::TokenStream) -> String {
+        stream.to_string()
+    }
+    fn from_token_tree(
+        &mut self,
+        tree: bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>,
+    ) -> Self::TokenStream {
+        match tree {
+            bridge::TokenTree::Group(group) => {
+                let group = Group {
+                    delimiter: delim_to_internal(group.delimiter, group.span),
+                    token_trees: match group.stream {
+                        Some(stream) => stream.into_iter().collect(),
+                        None => Vec::new(),
+                    },
+                };
+                let tree = TokenTree::from(group);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Ident(ident) => {
+                let text = ident.sym.text(self.interner);
+                let text =
+                    if ident.is_raw { ::tt::SmolStr::from_iter(["r#", &text]) } else { text };
+                let ident: tt::Ident = tt::Ident { text, span: ident.span };
+                let leaf = tt::Leaf::from(ident);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Literal(literal) => {
+                let literal = LiteralFormatter(literal);
+                let text = literal.with_stringify_parts(self.interner, |parts| {
+                    ::tt::SmolStr::from_iter(parts.iter().copied())
+                });
+
+                let literal = tt::Literal { text, span: literal.0.span };
+                let leaf = tt::Leaf::from(literal);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Punct(p) => {
+                let punct = tt::Punct {
+                    char: p.ch as char,
+                    spacing: if p.joint { Spacing::Joint } else { Spacing::Alone },
+                    span: p.span,
+                };
+                let leaf = tt::Leaf::from(punct);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+        }
+    }
+
+    fn expand_expr(&mut self, self_: &Self::TokenStream) -> Result<Self::TokenStream, ()> {
+        Ok(self_.clone())
+    }
+
+    fn concat_trees(
+        &mut self,
+        base: Option<Self::TokenStream>,
+        trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
+    ) -> Self::TokenStream {
+        let mut builder = TokenStreamBuilder::new();
+        if let Some(base) = base {
+            builder.push(base);
+        }
+        for tree in trees {
+            builder.push(self.from_token_tree(tree));
+        }
+        builder.build()
+    }
+
+    fn concat_streams(
+        &mut self,
+        base: Option<Self::TokenStream>,
+        streams: Vec<Self::TokenStream>,
+    ) -> Self::TokenStream {
+        let mut builder = TokenStreamBuilder::new();
+        if let Some(base) = base {
+            builder.push(base);
+        }
+        for stream in streams {
+            builder.push(stream);
+        }
+        builder.build()
+    }
+
+    fn into_trees(
+        &mut self,
+        stream: Self::TokenStream,
+    ) -> Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>> {
+        stream
+            .into_iter()
+            .map(|tree| match tree {
+                tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
+                    bridge::TokenTree::Ident(bridge::Ident {
+                        sym: Symbol::intern(self.interner, ident.text.trim_start_matches("r#")),
+                        is_raw: ident.text.starts_with("r#"),
+                        span: ident.span,
+                    })
+                }
+                tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) => {
+                    bridge::TokenTree::Literal(bridge::Literal {
+                        // FIXME: handle literal kinds
+                        kind: bridge::LitKind::Err,
+                        symbol: Symbol::intern(self.interner, &lit.text),
+                        // FIXME: handle suffixes
+                        suffix: None,
+                        span: lit.span,
+                    })
+                }
+                tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => {
+                    bridge::TokenTree::Punct(bridge::Punct {
+                        ch: punct.char as u8,
+                        joint: punct.spacing == Spacing::Joint,
+                        span: punct.span,
+                    })
+                }
+                tt::TokenTree::Subtree(subtree) => bridge::TokenTree::Group(bridge::Group {
+                    delimiter: delim_to_external(subtree.delimiter),
+                    stream: if subtree.token_trees.is_empty() {
+                        None
+                    } else {
+                        Some(subtree.token_trees.into_iter().collect())
+                    },
+                    span: bridge::DelimSpan::from_single(subtree.delimiter.open),
+                }),
+            })
+            .collect()
+    }
+}
+
+impl server::SourceFile for RaSpanServer {
+    // FIXME these are all stubs
+    fn eq(&mut self, _file1: &Self::SourceFile, _file2: &Self::SourceFile) -> bool {
+        true
+    }
+    fn path(&mut self, _file: &Self::SourceFile) -> String {
+        String::new()
+    }
+    fn is_real(&mut self, _file: &Self::SourceFile) -> bool {
+        true
+    }
+}
+
+impl server::Span for RaSpanServer {
+    fn debug(&mut self, span: Self::Span) -> String {
+        format!("{:?}", span)
+    }
+    fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
+        SourceFile {}
+    }
+    fn save_span(&mut self, _span: Self::Span) -> usize {
+        // FIXME stub
+        0
+    }
+    fn recover_proc_macro_span(&mut self, _id: usize) -> Self::Span {
+        // FIXME stub
+        self.call_site
+    }
+    /// Recent feature, not yet in the proc_macro
+    ///
+    /// See PR:
+    /// https://github.com/rust-lang/rust/pull/55780
+    fn source_text(&mut self, _span: Self::Span) -> Option<String> {
+        None
+    }
+
+    fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
+        // FIXME handle span
+        None
+    }
+    fn source(&mut self, span: Self::Span) -> Self::Span {
+        // FIXME handle span
+        span
+    }
+    fn byte_range(&mut self, _span: Self::Span) -> Range<usize> {
+        // FIXME handle span
+        Range { start: 0, end: 0 }
+    }
+    fn join(&mut self, first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
+        // Just return the first span again, because some macros will unwrap the result.
+        Some(first)
+    }
+    fn subspan(
+        &mut self,
+        span: Self::Span,
+        _start: Bound<usize>,
+        _end: Bound<usize>,
+    ) -> Option<Self::Span> {
+        // Just return the span again, because some macros will unwrap the result.
+        Some(span)
+    }
+    fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
+        // FIXME handle span
+        self.call_site
+    }
+
+    fn end(&mut self, _self_: Self::Span) -> Self::Span {
+        self.call_site
+    }
+
+    fn start(&mut self, _self_: Self::Span) -> Self::Span {
+        self.call_site
+    }
+
+    fn line(&mut self, _span: Self::Span) -> usize {
+        // FIXME handle line
+        0
+    }
+
+    fn column(&mut self, _span: Self::Span) -> usize {
+        // FIXME handle column
+        0
+    }
+}
+
+impl server::Symbol for RaSpanServer {
+    fn normalize_and_validate_ident(&mut self, string: &str) -> Result<Self::Symbol, ()> {
+        // FIXME: nfc-normalize and validate idents
+        Ok(<Self as server::Server>::intern_symbol(string))
+    }
+}
+
+impl server::Server for RaSpanServer {
+    fn globals(&mut self) -> bridge::ExpnGlobals<Self::Span> {
+        bridge::ExpnGlobals {
+            def_site: self.def_site,
+            call_site: self.call_site,
+            mixed_site: self.mixed_site,
+        }
+    }
+
+    fn intern_symbol(ident: &str) -> Self::Symbol {
+        // FIXME: should be `self.interner` once the proc-macro api allows it.
+        Symbol::intern(&SYMBOL_INTERNER, &::tt::SmolStr::from(ident))
+    }
+
+    fn with_symbol_string(symbol: &Self::Symbol, f: impl FnOnce(&str)) {
+        // FIXME: should be `self.interner` once the proc-macro api allows it.
+        f(symbol.text(&SYMBOL_INTERNER).as_str())
+    }
+}
diff --git a/crates/proc-macro-srv/src/server/token_id.rs b/crates/proc-macro-srv/src/server/token_id.rs
new file mode 100644
index 00000000000..01ca7488fa8
--- /dev/null
+++ b/crates/proc-macro-srv/src/server/token_id.rs
@@ -0,0 +1,375 @@
+use std::{
+    iter,
+    ops::{Bound, Range},
+};
+
+use proc_macro::bridge::{self, server};
+
+use crate::server::{
+    delim_to_external, delim_to_internal, token_stream::TokenStreamBuilder, LiteralFormatter,
+    Symbol, SymbolInternerRef, SYMBOL_INTERNER,
+};
+mod tt {
+    pub use proc_macro_api::msg::TokenId;
+
+    pub use ::tt::*;
+
+    pub type Subtree = ::tt::Subtree<TokenId>;
+    pub type TokenTree = ::tt::TokenTree<TokenId>;
+    pub type Leaf = ::tt::Leaf<TokenId>;
+    pub type Literal = ::tt::Literal<TokenId>;
+    pub type Punct = ::tt::Punct<TokenId>;
+    pub type Ident = ::tt::Ident<TokenId>;
+}
+type Group = tt::Subtree;
+type TokenTree = tt::TokenTree;
+#[allow(unused)]
+type Punct = tt::Punct;
+type Spacing = tt::Spacing;
+#[allow(unused)]
+type Literal = tt::Literal;
+type Span = tt::TokenId;
+type TokenStream = crate::server::TokenStream<Span>;
+
+#[derive(Clone)]
+pub struct SourceFile;
+pub struct FreeFunctions;
+
+pub struct TokenIdServer {
+    pub(crate) interner: SymbolInternerRef,
+    pub call_site: Span,
+    pub def_site: Span,
+    pub mixed_site: Span,
+}
+
+impl server::Types for TokenIdServer {
+    type FreeFunctions = FreeFunctions;
+    type TokenStream = TokenStream;
+    type SourceFile = SourceFile;
+    type Span = Span;
+    type Symbol = Symbol;
+}
+
+impl server::FreeFunctions for TokenIdServer {
+    fn track_env_var(&mut self, _var: &str, _value: Option<&str>) {}
+    fn track_path(&mut self, _path: &str) {}
+    fn literal_from_str(
+        &mut self,
+        s: &str,
+    ) -> Result<bridge::Literal<Self::Span, Self::Symbol>, ()> {
+        // FIXME: keep track of LitKind and Suffix
+        Ok(bridge::Literal {
+            kind: bridge::LitKind::Err,
+            symbol: Symbol::intern(self.interner, s),
+            suffix: None,
+            span: self.call_site,
+        })
+    }
+
+    fn emit_diagnostic(&mut self, _: bridge::Diagnostic<Self::Span>) {}
+}
+
+impl server::TokenStream for TokenIdServer {
+    fn is_empty(&mut self, stream: &Self::TokenStream) -> bool {
+        stream.is_empty()
+    }
+    fn from_str(&mut self, src: &str) -> Self::TokenStream {
+        Self::TokenStream::from_str(src, self.call_site).expect("cannot parse string")
+    }
+    fn to_string(&mut self, stream: &Self::TokenStream) -> String {
+        stream.to_string()
+    }
+    fn from_token_tree(
+        &mut self,
+        tree: bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>,
+    ) -> Self::TokenStream {
+        match tree {
+            bridge::TokenTree::Group(group) => {
+                let group = Group {
+                    delimiter: delim_to_internal(group.delimiter, group.span),
+                    token_trees: match group.stream {
+                        Some(stream) => stream.into_iter().collect(),
+                        None => Vec::new(),
+                    },
+                };
+                let tree = TokenTree::from(group);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Ident(ident) => {
+                let text = ident.sym.text(self.interner);
+                let text =
+                    if ident.is_raw { ::tt::SmolStr::from_iter(["r#", &text]) } else { text };
+                let ident: tt::Ident = tt::Ident { text, span: ident.span };
+                let leaf = tt::Leaf::from(ident);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Literal(literal) => {
+                let literal = LiteralFormatter(literal);
+                let text = literal.with_stringify_parts(self.interner, |parts| {
+                    ::tt::SmolStr::from_iter(parts.iter().copied())
+                });
+
+                let literal = tt::Literal { text, span: literal.0.span };
+                let leaf = tt::Leaf::from(literal);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+
+            bridge::TokenTree::Punct(p) => {
+                let punct = tt::Punct {
+                    char: p.ch as char,
+                    spacing: if p.joint { Spacing::Joint } else { Spacing::Alone },
+                    span: p.span,
+                };
+                let leaf = tt::Leaf::from(punct);
+                let tree = TokenTree::from(leaf);
+                Self::TokenStream::from_iter(iter::once(tree))
+            }
+        }
+    }
+
+    fn expand_expr(&mut self, self_: &Self::TokenStream) -> Result<Self::TokenStream, ()> {
+        Ok(self_.clone())
+    }
+
+    fn concat_trees(
+        &mut self,
+        base: Option<Self::TokenStream>,
+        trees: Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>>,
+    ) -> Self::TokenStream {
+        let mut builder = TokenStreamBuilder::new();
+        if let Some(base) = base {
+            builder.push(base);
+        }
+        for tree in trees {
+            builder.push(self.from_token_tree(tree));
+        }
+        builder.build()
+    }
+
+    fn concat_streams(
+        &mut self,
+        base: Option<Self::TokenStream>,
+        streams: Vec<Self::TokenStream>,
+    ) -> Self::TokenStream {
+        let mut builder = TokenStreamBuilder::new();
+        if let Some(base) = base {
+            builder.push(base);
+        }
+        for stream in streams {
+            builder.push(stream);
+        }
+        builder.build()
+    }
+
+    fn into_trees(
+        &mut self,
+        stream: Self::TokenStream,
+    ) -> Vec<bridge::TokenTree<Self::TokenStream, Self::Span, Self::Symbol>> {
+        stream
+            .into_iter()
+            .map(|tree| match tree {
+                tt::TokenTree::Leaf(tt::Leaf::Ident(ident)) => {
+                    bridge::TokenTree::Ident(bridge::Ident {
+                        sym: Symbol::intern(self.interner, ident.text.trim_start_matches("r#")),
+                        is_raw: ident.text.starts_with("r#"),
+                        span: ident.span,
+                    })
+                }
+                tt::TokenTree::Leaf(tt::Leaf::Literal(lit)) => {
+                    bridge::TokenTree::Literal(bridge::Literal {
+                        // FIXME: handle literal kinds
+                        kind: bridge::LitKind::Err,
+                        symbol: Symbol::intern(self.interner, &lit.text),
+                        // FIXME: handle suffixes
+                        suffix: None,
+                        span: lit.span,
+                    })
+                }
+                tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) => {
+                    bridge::TokenTree::Punct(bridge::Punct {
+                        ch: punct.char as u8,
+                        joint: punct.spacing == Spacing::Joint,
+                        span: punct.span,
+                    })
+                }
+                tt::TokenTree::Subtree(subtree) => bridge::TokenTree::Group(bridge::Group {
+                    delimiter: delim_to_external(subtree.delimiter),
+                    stream: if subtree.token_trees.is_empty() {
+                        None
+                    } else {
+                        Some(subtree.token_trees.into_iter().collect())
+                    },
+                    span: bridge::DelimSpan::from_single(subtree.delimiter.open),
+                }),
+            })
+            .collect()
+    }
+}
+
+impl server::SourceFile for TokenIdServer {
+    fn eq(&mut self, _file1: &Self::SourceFile, _file2: &Self::SourceFile) -> bool {
+        true
+    }
+    fn path(&mut self, _file: &Self::SourceFile) -> String {
+        String::new()
+    }
+    fn is_real(&mut self, _file: &Self::SourceFile) -> bool {
+        true
+    }
+}
+
+impl server::Span for TokenIdServer {
+    fn debug(&mut self, span: Self::Span) -> String {
+        format!("{:?}", span.0)
+    }
+    fn source_file(&mut self, _span: Self::Span) -> Self::SourceFile {
+        SourceFile {}
+    }
+    fn save_span(&mut self, _span: Self::Span) -> usize {
+        0
+    }
+    fn recover_proc_macro_span(&mut self, _id: usize) -> Self::Span {
+        self.call_site
+    }
+    /// Recent feature, not yet in the proc_macro
+    ///
+    /// See PR:
+    /// https://github.com/rust-lang/rust/pull/55780
+    fn source_text(&mut self, _span: Self::Span) -> Option<String> {
+        None
+    }
+
+    fn parent(&mut self, _span: Self::Span) -> Option<Self::Span> {
+        None
+    }
+    fn source(&mut self, span: Self::Span) -> Self::Span {
+        span
+    }
+    fn byte_range(&mut self, _span: Self::Span) -> Range<usize> {
+        Range { start: 0, end: 0 }
+    }
+    fn join(&mut self, first: Self::Span, _second: Self::Span) -> Option<Self::Span> {
+        // Just return the first span again, because some macros will unwrap the result.
+        Some(first)
+    }
+    fn subspan(
+        &mut self,
+        span: Self::Span,
+        _start: Bound<usize>,
+        _end: Bound<usize>,
+    ) -> Option<Self::Span> {
+        // Just return the span again, because some macros will unwrap the result.
+        Some(span)
+    }
+    fn resolved_at(&mut self, _span: Self::Span, _at: Self::Span) -> Self::Span {
+        self.call_site
+    }
+
+    fn end(&mut self, _self_: Self::Span) -> Self::Span {
+        self.call_site
+    }
+
+    fn start(&mut self, _self_: Self::Span) -> Self::Span {
+        self.call_site
+    }
+
+    fn line(&mut self, _span: Self::Span) -> usize {
+        0
+    }
+
+    fn column(&mut self, _span: Self::Span) -> usize {
+        0
+    }
+}
+
+impl server::Symbol for TokenIdServer {
+    fn normalize_and_validate_ident(&mut self, string: &str) -> Result<Self::Symbol, ()> {
+        // FIXME: nfc-normalize and validate idents
+        Ok(<Self as server::Server>::intern_symbol(string))
+    }
+}
+
+impl server::Server for TokenIdServer {
+    fn globals(&mut self) -> bridge::ExpnGlobals<Self::Span> {
+        bridge::ExpnGlobals {
+            def_site: self.def_site,
+            call_site: self.call_site,
+            mixed_site: self.mixed_site,
+        }
+    }
+
+    fn intern_symbol(ident: &str) -> Self::Symbol {
+        Symbol::intern(&SYMBOL_INTERNER, &::tt::SmolStr::from(ident))
+    }
+
+    fn with_symbol_string(symbol: &Self::Symbol, f: impl FnOnce(&str)) {
+        f(symbol.text(&SYMBOL_INTERNER).as_str())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_ra_server_to_string() {
+        let s = TokenStream {
+            token_trees: vec![
+                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                    text: "struct".into(),
+                    span: tt::TokenId(0),
+                })),
+                tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                    text: "T".into(),
+                    span: tt::TokenId(0),
+                })),
+                tt::TokenTree::Subtree(tt::Subtree {
+                    delimiter: tt::Delimiter {
+                        open: tt::TokenId(0),
+                        close: tt::TokenId(0),
+                        kind: tt::DelimiterKind::Brace,
+                    },
+                    token_trees: vec![],
+                }),
+            ],
+        };
+
+        assert_eq!(s.to_string(), "struct T {}");
+    }
+
+    #[test]
+    fn test_ra_server_from_str() {
+        let subtree_paren_a = tt::TokenTree::Subtree(tt::Subtree {
+            delimiter: tt::Delimiter {
+                open: tt::TokenId(0),
+                close: tt::TokenId(0),
+                kind: tt::DelimiterKind::Parenthesis,
+            },
+            token_trees: vec![tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                text: "a".into(),
+                span: tt::TokenId(0),
+            }))],
+        });
+
+        let t1 = TokenStream::from_str("(a)", tt::TokenId(0)).unwrap();
+        assert_eq!(t1.token_trees.len(), 1);
+        assert_eq!(t1.token_trees[0], subtree_paren_a);
+
+        let t2 = TokenStream::from_str("(a);", tt::TokenId(0)).unwrap();
+        assert_eq!(t2.token_trees.len(), 2);
+        assert_eq!(t2.token_trees[0], subtree_paren_a);
+
+        let underscore = TokenStream::from_str("_", tt::TokenId(0)).unwrap();
+        assert_eq!(
+            underscore.token_trees[0],
+            tt::TokenTree::Leaf(tt::Leaf::Ident(tt::Ident {
+                text: "_".into(),
+                span: tt::TokenId(0),
+            }))
+        );
+    }
+}
diff --git a/crates/proc-macro-srv/src/server/token_stream.rs b/crates/proc-macro-srv/src/server/token_stream.rs
index 36be8825038..93f2e01addd 100644
--- a/crates/proc-macro-srv/src/server/token_stream.rs
+++ b/crates/proc-macro-srv/src/server/token_stream.rs
@@ -1,20 +1,24 @@
 //! TokenStream implementation used by sysroot ABI
 
-use proc_macro_api::msg::TokenId;
+use tt::TokenTree;
 
-use crate::tt::{self, TokenTree};
+#[derive(Debug, Clone)]
+pub struct TokenStream<S> {
+    pub(super) token_trees: Vec<TokenTree<S>>,
+}
 
-#[derive(Debug, Default, Clone)]
-pub struct TokenStream {
-    pub(super) token_trees: Vec<TokenTree>,
+impl<S> Default for TokenStream<S> {
+    fn default() -> Self {
+        Self { token_trees: vec![] }
+    }
 }
 
-impl TokenStream {
+impl<S> TokenStream<S> {
     pub(crate) fn new() -> Self {
-        TokenStream::default()
+        TokenStream { token_trees: vec![] }
     }
 
-    pub(crate) fn with_subtree(subtree: tt::Subtree) -> Self {
+    pub(crate) fn with_subtree(subtree: tt::Subtree<S>) -> Self {
         if subtree.delimiter.kind != tt::DelimiterKind::Invisible {
             TokenStream { token_trees: vec![TokenTree::Subtree(subtree)] }
         } else {
@@ -22,7 +26,10 @@ impl TokenStream {
         }
     }
 
-    pub(crate) fn into_subtree(self, call_site: TokenId) -> tt::Subtree {
+    pub(crate) fn into_subtree(self, call_site: S) -> tt::Subtree<S>
+    where
+        S: Copy,
+    {
         tt::Subtree {
             delimiter: tt::Delimiter {
                 open: call_site,
@@ -39,37 +46,37 @@ impl TokenStream {
 }
 
 /// Creates a token stream containing a single token tree.
-impl From<TokenTree> for TokenStream {
-    fn from(tree: TokenTree) -> TokenStream {
+impl<S> From<TokenTree<S>> for TokenStream<S> {
+    fn from(tree: TokenTree<S>) -> TokenStream<S> {
         TokenStream { token_trees: vec![tree] }
     }
 }
 
 /// Collects a number of token trees into a single stream.
-impl FromIterator<TokenTree> for TokenStream {
-    fn from_iter<I: IntoIterator<Item = TokenTree>>(trees: I) -> Self {
+impl<S> FromIterator<TokenTree<S>> for TokenStream<S> {
+    fn from_iter<I: IntoIterator<Item = TokenTree<S>>>(trees: I) -> Self {
         trees.into_iter().map(TokenStream::from).collect()
     }
 }
 
 /// A "flattening" operation on token streams, collects token trees
 /// from multiple token streams into a single stream.
-impl FromIterator<TokenStream> for TokenStream {
-    fn from_iter<I: IntoIterator<Item = TokenStream>>(streams: I) -> Self {
+impl<S> FromIterator<TokenStream<S>> for TokenStream<S> {
+    fn from_iter<I: IntoIterator<Item = TokenStream<S>>>(streams: I) -> Self {
         let mut builder = TokenStreamBuilder::new();
         streams.into_iter().for_each(|stream| builder.push(stream));
         builder.build()
     }
 }
 
-impl Extend<TokenTree> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenTree>>(&mut self, trees: I) {
+impl<S> Extend<TokenTree<S>> for TokenStream<S> {
+    fn extend<I: IntoIterator<Item = TokenTree<S>>>(&mut self, trees: I) {
         self.extend(trees.into_iter().map(TokenStream::from));
     }
 }
 
-impl Extend<TokenStream> for TokenStream {
-    fn extend<I: IntoIterator<Item = TokenStream>>(&mut self, streams: I) {
+impl<S> Extend<TokenStream<S>> for TokenStream<S> {
+    fn extend<I: IntoIterator<Item = TokenStream<S>>>(&mut self, streams: I) {
         for item in streams {
             for tkn in item {
                 match tkn {
@@ -87,22 +94,21 @@ impl Extend<TokenStream> for TokenStream {
     }
 }
 
-pub(super) struct TokenStreamBuilder {
-    acc: TokenStream,
+pub(super) struct TokenStreamBuilder<S> {
+    acc: TokenStream<S>,
 }
 
 /// pub(super)lic implementation details for the `TokenStream` type, such as iterators.
 pub(super) mod token_stream {
-    use proc_macro_api::msg::TokenId;
 
-    use super::{tt, TokenStream, TokenTree};
+    use super::{TokenStream, TokenTree};
 
     /// An iterator over `TokenStream`'s `TokenTree`s.
     /// The iteration is "shallow", e.g., the iterator doesn't recurse into delimited groups,
     /// and returns whole groups as token trees.
-    impl IntoIterator for TokenStream {
-        type Item = TokenTree;
-        type IntoIter = std::vec::IntoIter<TokenTree>;
+    impl<S> IntoIterator for TokenStream<S> {
+        type Item = TokenTree<S>;
+        type IntoIter = std::vec::IntoIter<TokenTree<S>>;
 
         fn into_iter(self) -> Self::IntoIter {
             self.token_trees.into_iter()
@@ -119,53 +125,52 @@ pub(super) mod token_stream {
     /// NOTE: some errors may cause panics instead of returning `LexError`. We reserve the right to
     /// change these errors into `LexError`s later.
     #[rustfmt::skip]
-    impl /*FromStr for*/ TokenStream {
+    impl<S: tt::Span> /*FromStr for*/ TokenStream<S> {
         // type Err = LexError;
 
-        pub(crate) fn from_str(src: &str, call_site: TokenId) -> Result<TokenStream, LexError> {
+        pub(crate) fn from_str(src: &str, call_site: S) -> Result<TokenStream<S>, LexError> {
             let subtree =
                 mbe::parse_to_token_tree_static_span(call_site, src).ok_or("Failed to parse from mbe")?;
 
-            let subtree = subtree_replace_token_ids_with_call_site(subtree,call_site);
             Ok(TokenStream::with_subtree(subtree))
         }
     }
 
-    impl ToString for TokenStream {
+    impl<S> ToString for TokenStream<S> {
         fn to_string(&self) -> String {
             ::tt::pretty(&self.token_trees)
         }
     }
 
-    fn subtree_replace_token_ids_with_call_site(
-        subtree: tt::Subtree,
-        call_site: TokenId,
-    ) -> tt::Subtree {
+    fn subtree_replace_spans_with_call_site<S: Copy>(
+        subtree: tt::Subtree<S>,
+        call_site: S,
+    ) -> tt::Subtree<S> {
         tt::Subtree {
             delimiter: tt::Delimiter { open: call_site, close: call_site, ..subtree.delimiter },
             token_trees: subtree
                 .token_trees
                 .into_iter()
-                .map(|it| token_tree_replace_token_ids_with_call_site(it, call_site))
+                .map(|it| token_tree_replace_spans_with_call_site(it, call_site))
                 .collect(),
         }
     }
 
-    fn token_tree_replace_token_ids_with_call_site(
-        tt: tt::TokenTree,
-        call_site: TokenId,
-    ) -> tt::TokenTree {
+    fn token_tree_replace_spans_with_call_site<S: Copy>(
+        tt: tt::TokenTree<S>,
+        call_site: S,
+    ) -> tt::TokenTree<S> {
         match tt {
             tt::TokenTree::Leaf(leaf) => {
-                tt::TokenTree::Leaf(leaf_replace_token_ids_with_call_site(leaf, call_site))
+                tt::TokenTree::Leaf(leaf_replace_spans_with_call_site(leaf, call_site))
             }
             tt::TokenTree::Subtree(subtree) => {
-                tt::TokenTree::Subtree(subtree_replace_token_ids_with_call_site(subtree, call_site))
+                tt::TokenTree::Subtree(subtree_replace_spans_with_call_site(subtree, call_site))
             }
         }
     }
 
-    fn leaf_replace_token_ids_with_call_site(leaf: tt::Leaf, call_site: TokenId) -> tt::Leaf {
+    fn leaf_replace_spans_with_call_site<S: Copy>(leaf: tt::Leaf<S>, call_site: S) -> tt::Leaf<S> {
         match leaf {
             tt::Leaf::Literal(lit) => tt::Leaf::Literal(tt::Literal { span: call_site, ..lit }),
             tt::Leaf::Punct(punct) => tt::Leaf::Punct(tt::Punct { span: call_site, ..punct }),
@@ -174,16 +179,16 @@ pub(super) mod token_stream {
     }
 }
 
-impl TokenStreamBuilder {
-    pub(super) fn new() -> TokenStreamBuilder {
+impl<S> TokenStreamBuilder<S> {
+    pub(super) fn new() -> TokenStreamBuilder<S> {
         TokenStreamBuilder { acc: TokenStream::new() }
     }
 
-    pub(super) fn push(&mut self, stream: TokenStream) {
+    pub(super) fn push(&mut self, stream: TokenStream<S>) {
         self.acc.extend(stream.into_iter())
     }
 
-    pub(super) fn build(self) -> TokenStream {
+    pub(super) fn build(self) -> TokenStream<S> {
         self.acc
     }
 }
diff --git a/crates/proc-macro-srv/src/tests/mod.rs b/crates/proc-macro-srv/src/tests/mod.rs
index b04e3ca19ac..1f4d1cf74ea 100644
--- a/crates/proc-macro-srv/src/tests/mod.rs
+++ b/crates/proc-macro-srv/src/tests/mod.rs
@@ -8,7 +8,7 @@ use expect_test::expect;
 
 #[test]
 fn test_derive_empty() {
-    assert_expand("DeriveEmpty", r#"struct S;"#, expect!["SUBTREE $$ 1 1"]);
+    assert_expand("DeriveEmpty", r#"struct S;"#, expect!["SUBTREE $$ 1 1"], expect!["SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"]);
 }
 
 #[test]
@@ -23,6 +23,13 @@ fn test_derive_error() {
               SUBTREE () 1 1
                 LITERAL "#[derive(DeriveError)] struct S ;" 1
               PUNCH   ; [alone] 1"##]],
+        expect![[r##"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   compile_error SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   ! [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              SUBTREE () SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+                LITERAL "#[derive(DeriveError)] struct S ;" SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   ; [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"##]],
     );
 }
 
@@ -40,6 +47,15 @@ fn test_fn_like_macro_noop() {
               LITERAL 1 1
               PUNCH   , [alone] 1
               SUBTREE [] 1 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   ident SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 0 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 1 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              SUBTREE [] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -53,6 +69,11 @@ fn test_fn_like_macro_clone_ident_subtree() {
               IDENT   ident 1
               PUNCH   , [alone] 1
               SUBTREE [] 1 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   ident SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              SUBTREE [] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -64,6 +85,9 @@ fn test_fn_like_macro_clone_raw_ident() {
         expect![[r#"
             SUBTREE $$ 1 1
               IDENT   r#async 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   r#async SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -81,6 +105,15 @@ fn test_fn_like_mk_literals() {
               LITERAL 3.14 1
               LITERAL 123i64 1
               LITERAL 123 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL b"byte_string" SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 'c' SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL "string" SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 3.14f64 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 3.14 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 123i64 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 123 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -93,6 +126,10 @@ fn test_fn_like_mk_idents() {
             SUBTREE $$ 1 1
               IDENT   standard 1
               IDENT   r#raw 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   standard SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   r#raw SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -113,6 +150,18 @@ fn test_fn_like_macro_clone_literals() {
               LITERAL 3.14f32 1
               PUNCH   , [alone] 1
               LITERAL "hello bridge" 1"#]],
+        expect![[r#"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 1u16 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 2_u32 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   - [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 4i64 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL 3.14f32 SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   , [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              LITERAL "hello bridge" SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"#]],
     );
 }
 
@@ -132,6 +181,13 @@ fn test_attr_macro() {
               SUBTREE () 1 1
                 LITERAL "#[attr_error(some arguments)] mod m {}" 1
               PUNCH   ; [alone] 1"##]],
+        expect![[r##"
+            SUBTREE $$ SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              IDENT   compile_error SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   ! [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              SUBTREE () SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) } SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+                LITERAL "#[attr_error(some arguments)] mod m {}" SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }
+              PUNCH   ; [alone] SpanData { range: 52..77, anchor: SpanAnchor(FileId(42), 2), ctx: SyntaxContextId(0) }"##]],
     );
 }
 
diff --git a/crates/proc-macro-srv/src/tests/utils.rs b/crates/proc-macro-srv/src/tests/utils.rs
index c12096d140c..9386e00117e 100644
--- a/crates/proc-macro-srv/src/tests/utils.rs
+++ b/crates/proc-macro-srv/src/tests/utils.rs
@@ -1,11 +1,16 @@
 //! utils used in proc-macro tests
 
+use base_db::{
+    span::{ErasedFileAstId, SpanAnchor, SpanData, SyntaxContextId},
+    FileId,
+};
 use expect_test::Expect;
-use proc_macro_api::msg::TokenId;
+use proc_macro_api::msg::{SpanDataIndexMap, TokenId};
+use tt::TextRange;
 
 use crate::{dylib, proc_macro_test_dylib_path, ProcMacroSrv};
 
-fn parse_string(code: &str, call_site: TokenId) -> Option<crate::server::TokenStream> {
+fn parse_string<S: tt::Span>(code: &str, call_site: S) -> Option<crate::server::TokenStream<S>> {
     // This is a bit strange. We need to parse a string into a token stream into
     // order to create a tt::SubTree from it in fixtures. `into_subtree` is
     // implemented by all the ABIs we have so we arbitrarily choose one ABI to
@@ -15,34 +20,73 @@ fn parse_string(code: &str, call_site: TokenId) -> Option<crate::server::TokenSt
     crate::server::TokenStream::from_str(code, call_site).ok()
 }
 
-pub fn assert_expand(macro_name: &str, ra_fixture: &str, expect: Expect) {
-    assert_expand_impl(macro_name, ra_fixture, None, expect);
+pub fn assert_expand(macro_name: &str, ra_fixture: &str, expect: Expect, expect_s: Expect) {
+    assert_expand_impl(macro_name, ra_fixture, None, expect, expect_s);
 }
 
-pub fn assert_expand_attr(macro_name: &str, ra_fixture: &str, attr_args: &str, expect: Expect) {
-    assert_expand_impl(macro_name, ra_fixture, Some(attr_args), expect);
+pub fn assert_expand_attr(
+    macro_name: &str,
+    ra_fixture: &str,
+    attr_args: &str,
+    expect: Expect,
+    expect_s: Expect,
+) {
+    assert_expand_impl(macro_name, ra_fixture, Some(attr_args), expect, expect_s);
 }
 
-fn assert_expand_impl(macro_name: &str, input: &str, attr: Option<&str>, expect: Expect) {
+fn assert_expand_impl(
+    macro_name: &str,
+    input: &str,
+    attr: Option<&str>,
+    expect: Expect,
+    expect_s: Expect,
+) {
+    let path = proc_macro_test_dylib_path();
+    let expander = dylib::Expander::new(&path).unwrap();
+
     let def_site = TokenId(0);
     let call_site = TokenId(1);
     let mixed_site = TokenId(2);
-    let path = proc_macro_test_dylib_path();
-    let expander = dylib::Expander::new(&path).unwrap();
-    let fixture = parse_string(input, call_site).unwrap();
-    let attr = attr.map(|attr| parse_string(attr, call_site).unwrap().into_subtree(call_site));
+    let input_ts = parse_string(input, call_site).unwrap();
+    let attr_ts = attr.map(|attr| parse_string(attr, call_site).unwrap().into_subtree(call_site));
 
     let res = expander
         .expand(
             macro_name,
-            &fixture.into_subtree(call_site),
-            attr.as_ref(),
+            input_ts.into_subtree(call_site),
+            attr_ts,
             def_site,
             call_site,
             mixed_site,
         )
         .unwrap();
     expect.assert_eq(&format!("{res:?}"));
+
+    let def_site = SpanData {
+        range: TextRange::new(0.into(), 150.into()),
+        anchor: SpanAnchor {
+            file_id: FileId::from_raw(41),
+            ast_id: ErasedFileAstId::from_raw(From::from(1)),
+        },
+        ctx: SyntaxContextId::ROOT,
+    };
+    let call_site = SpanData {
+        range: TextRange::new(52.into(), 77.into()),
+        anchor: SpanAnchor {
+            file_id: FileId::from_raw(42),
+            ast_id: ErasedFileAstId::from_raw(From::from(2)),
+        },
+        ctx: SyntaxContextId::ROOT,
+    };
+    let mixed_site = call_site;
+
+    let fixture = parse_string(input, call_site).unwrap();
+    let attr = attr.map(|attr| parse_string(attr, call_site).unwrap().into_subtree(call_site));
+
+    let res = expander
+        .expand(macro_name, fixture.into_subtree(call_site), attr, def_site, call_site, mixed_site)
+        .unwrap();
+    expect_s.assert_eq(&format!("{res:?}"));
 }
 
 pub(crate) fn list() -> Vec<String> {
diff --git a/crates/span/src/lib.rs b/crates/span/src/lib.rs
index 09af34ce7e0..7341a529a65 100644
--- a/crates/span/src/lib.rs
+++ b/crates/span/src/lib.rs
@@ -97,6 +97,14 @@ impl SyntaxContextId {
     pub fn is_root(self) -> bool {
         self == Self::ROOT
     }
+
+    pub fn into_u32(self) -> u32 {
+        self.0.as_u32()
+    }
+
+    pub fn from_u32(u32: u32) -> Self {
+        Self(InternId::from(u32))
+    }
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]