Remove lossy `Definition::from_token`/`Definition::from_node` methods

6 files changed, 91 insertions, 92 deletions

diff --git a/crates/ide/src/goto_definition.rs b/crates/ide/src/goto_definition.rs
index 4d638e687ae..29fc1fd2e03 100644
--- a/crates/ide/src/goto_definition.rs
+++ b/crates/ide/src/goto_definition.rs
@@ -4,7 +4,7 @@ use crate::{doc_links::token_as_doc_comment, FilePosition, NavigationTarget, Ran
 use hir::{AsAssocItem, Semantics};
 use ide_db::{
     base_db::{AnchoredPath, FileId, FileLoader},
-    defs::Definition,
+    defs::{Definition, IdentClass},
     helpers::pick_best_token,
     RootDatabase,
 };
@@ -46,20 +46,20 @@ pub(crate) fn goto_definition(
         .filter_map(|token| {
             let parent = token.parent()?;
             if let Some(tt) = ast::TokenTree::cast(parent) {
-                if let x @ Some(_) =
-                    try_lookup_include_path(sema, tt, token.clone(), position.file_id)
+                if let Some(x) = try_lookup_include_path(sema, tt, token.clone(), position.file_id)
                 {
-                    return x;
+                    return Some(vec![x]);
                 }
             }
             Some(
-                Definition::from_token(sema, &token)
+                IdentClass::classify_token(sema, &token)?
+                    .definitions()
                     .into_iter()
                     .flat_map(|def| {
                         try_find_trait_item_definition(sema.db, &def)
                             .unwrap_or_else(|| def_to_nav(sema.db, def))
                     })
-                    .collect::<Vec<_>>(),
+                    .collect(),
             )
         })
         .flatten()
@@ -74,7 +74,7 @@ fn try_lookup_include_path(
     tt: ast::TokenTree,
     token: SyntaxToken,
     file_id: FileId,
-) -> Option<Vec<NavigationTarget>> {
+) -> Option<NavigationTarget> {
     let token = ast::String::cast(token)?;
     let path = token.value()?.into_owned();
     let macro_call = tt.syntax().parent().and_then(ast::MacroCall::cast)?;
@@ -84,7 +84,7 @@ fn try_lookup_include_path(
     }
     let file_id = sema.db.resolve_path(AnchoredPath { anchor: file_id, path: &path })?;
     let size = sema.db.file_text(file_id).len().try_into().ok()?;
-    Some(vec![NavigationTarget {
+    Some(NavigationTarget {
         file_id,
         full_range: TextRange::new(0.into(), size),
         name: path.into(),
@@ -93,7 +93,7 @@ fn try_lookup_include_path(
         container_name: None,
         description: None,
         docs: None,
-    }])
+    })
 }
 
 /// finds the trait definition of an impl'd item
diff --git a/crates/ide/src/highlight_related.rs b/crates/ide/src/highlight_related.rs
index 054b8f297b5..b6d9e4021d9 100644
--- a/crates/ide/src/highlight_related.rs
+++ b/crates/ide/src/highlight_related.rs
@@ -1,7 +1,7 @@
 use hir::Semantics;
 use ide_db::{
     base_db::{FileId, FilePosition},
-    defs::Definition,
+    defs::{Definition, IdentClass},
     helpers::{for_each_break_expr, for_each_tail_expr, node_ext::walk_expr, pick_best_token},
     search::{FileReference, ReferenceCategory, SearchScope},
     RootDatabase,
@@ -293,7 +293,8 @@ fn cover_range(r0: Option<TextRange>, r1: Option<TextRange>) -> Option<TextRange
 fn find_defs(sema: &Semantics<RootDatabase>, token: SyntaxToken) -> FxHashSet<Definition> {
     sema.descend_into_macros(token)
         .into_iter()
-        .flat_map(|token| Definition::from_token(sema, &token))
+        .filter_map(|token| IdentClass::classify_token(sema, &token).map(IdentClass::definitions))
+        .flatten()
         .collect()
 }
 
diff --git a/crates/ide/src/hover.rs b/crates/ide/src/hover.rs
index 9d19d7c1c01..21bea25a5f7 100644
--- a/crates/ide/src/hover.rs
+++ b/crates/ide/src/hover.rs
@@ -9,7 +9,7 @@ use either::Either;
 use hir::{HasSource, Semantics};
 use ide_db::{
     base_db::FileRange,
-    defs::Definition,
+    defs::{Definition, IdentClass},
     helpers::{pick_best_token, FamousDefs},
     FxIndexSet, RootDatabase,
 };
@@ -129,8 +129,8 @@ pub(crate) fn hover(
         .iter()
         .filter_map(|token| {
             let node = token.parent()?;
-            let defs = Definition::from_token(sema, token);
-            Some(defs.into_iter().zip(iter::once(node).cycle()))
+            let class = IdentClass::classify_token(sema, token)?;
+            Some(class.definitions().into_iter().zip(iter::once(node).cycle()))
         })
         .flatten()
         .unique_by(|&(def, _)| def)
diff --git a/crates/ide/src/moniker.rs b/crates/ide/src/moniker.rs
index c93c471f494..53f6d7ec7ad 100644
--- a/crates/ide/src/moniker.rs
+++ b/crates/ide/src/moniker.rs
@@ -4,7 +4,7 @@
 use hir::{db::DefDatabase, AsAssocItem, AssocItemContainer, Crate, Name, Semantics};
 use ide_db::{
     base_db::{CrateOrigin, FileId, FileLoader, FilePosition},
-    defs::Definition,
+    defs::{Definition, IdentClass},
     helpers::pick_best_token,
     RootDatabase,
 };
@@ -82,11 +82,10 @@ pub(crate) fn moniker(
     let navs = sema
         .descend_into_macros(original_token.clone())
         .into_iter()
-        .map(|token| {
-            Definition::from_token(sema, &token)
-                .into_iter()
-                .flat_map(|def| def_to_moniker(sema.db, def, current_crate))
-                .collect::<Vec<_>>()
+        .filter_map(|token| {
+            IdentClass::classify_token(sema, &token).map(IdentClass::definitions).map(|it| {
+                it.into_iter().flat_map(|def| def_to_moniker(sema.db, def, current_crate))
+            })
         })
         .flatten()
         .unique()
diff --git a/crates/ide/src/static_index.rs b/crates/ide/src/static_index.rs
index 77d202cc39c..d5bfbd18941 100644
--- a/crates/ide/src/static_index.rs
+++ b/crates/ide/src/static_index.rs
@@ -6,7 +6,7 @@ use std::collections::HashMap;
 use hir::{db::HirDatabase, Crate, Module, Semantics};
 use ide_db::{
     base_db::{FileId, FileRange, SourceDatabaseExt},
-    defs::Definition,
+    defs::{Definition, IdentClass},
     RootDatabase,
 };
 use rustc_hash::FxHashSet;
@@ -195,9 +195,9 @@ impl StaticIndex<'_> {
 
 fn get_definition(sema: &Semantics<RootDatabase>, token: SyntaxToken) -> Option<Definition> {
     for token in sema.descend_into_macros(token) {
-        let def = Definition::from_token(sema, &token);
-        if let [x] = def.as_slice() {
-            return Some(*x);
+        let def = IdentClass::classify_token(sema, &token).map(IdentClass::definitions);
+        if let Some(&[x]) = def.as_deref() {
+            return Some(x);
         } else {
             continue;
         };
diff --git a/crates/ide_db/src/defs.rs b/crates/ide_db/src/defs.rs
index 1501c4eda53..172acdbc3c4 100644
--- a/crates/ide_db/src/defs.rs
+++ b/crates/ide_db/src/defs.rs
@@ -42,74 +42,6 @@ pub enum Definition {
 }
 
 impl Definition {
-    pub fn from_token(
-        sema: &Semantics<RootDatabase>,
-        token: &SyntaxToken,
-    ) -> ArrayVec<Definition, 2> {
-        let parent = match token.parent() {
-            Some(parent) => parent,
-            None => return Default::default(),
-        };
-        // resolve derives if possible
-        if let Some(ident) = ast::Ident::cast(token.clone()) {
-            let attr = ast::TokenTree::cast(parent.clone())
-                .and_then(|tt| tt.parent_meta())
-                .and_then(|meta| meta.parent_attr());
-            if let Some(attr) = attr {
-                return sema
-                    .resolve_derive_ident(&attr, &ident)
-                    .map(Into::into)
-                    .into_iter()
-                    .collect();
-            }
-        }
-        Self::from_node(sema, &parent)
-    }
-
-    pub fn from_node(sema: &Semantics<RootDatabase>, node: &SyntaxNode) -> ArrayVec<Definition, 2> {
-        let mut res = ArrayVec::new();
-        (|| {
-            match_ast! {
-                match node {
-                    ast::Name(name) => {
-                        match NameClass::classify(&sema, &name)? {
-                            NameClass::Definition(it) | NameClass::ConstReference(it) => res.push(it),
-                            NameClass::PatFieldShorthand { local_def, field_ref } => {
-                                res.push(Definition::Local(local_def));
-                                res.push(Definition::Field(field_ref));
-                            }
-                        }
-                    },
-                    ast::NameRef(name_ref) => {
-                        match NameRefClass::classify(sema, &name_ref)? {
-                            NameRefClass::Definition(it) => res.push(it),
-                            NameRefClass::FieldShorthand { local_ref, field_ref } => {
-                                res.push(Definition::Local(local_ref));
-                                res.push(Definition::Field(field_ref));
-                            }
-                        }
-                    },
-                    ast::Lifetime(lifetime) => {
-                        let def = if let Some(x) = NameClass::classify_lifetime(&sema, &lifetime) {
-                            NameClass::defined(x)
-                        } else {
-                            NameRefClass::classify_lifetime(&sema, &lifetime).and_then(|class| match class {
-                                NameRefClass::Definition(it) => Some(it),
-                                _ => None,
-                            })
-                        };
-                        if let Some(def) = def {
-                            res.push(def);
-                        }
-                    },
-                    _ => (),
-                }
-            }
-            Some(())
-        })();
-        res
-    }
-
     pub fn canonical_module_path(&self, db: &RootDatabase) -> Option<impl Iterator<Item = Module>> {
         self.module(db).map(|it| it.path_to_root(db).into_iter().rev())
     }
@@ -184,6 +116,65 @@ impl Definition {
     }
 }
 
+pub enum IdentClass {
+    NameClass(NameClass),
+    NameRefClass(NameRefClass),
+}
+
+impl IdentClass {
+    pub fn classify_node(sema: &Semantics<RootDatabase>, node: &SyntaxNode) -> Option<IdentClass> {
+        match_ast! {
+            match node {
+                ast::Name(name) => NameClass::classify(sema, &name).map(IdentClass::NameClass),
+                ast::NameRef(name_ref) => NameRefClass::classify(sema, &name_ref).map(IdentClass::NameRefClass),
+                ast::Lifetime(lifetime) => {
+                    NameClass::classify_lifetime(sema, &lifetime)
+                        .map(IdentClass::NameClass)
+                        .or_else(|| NameRefClass::classify_lifetime(sema, &lifetime).map(IdentClass::NameRefClass))
+                },
+                _ => None,
+            }
+        }
+    }
+
+    pub fn classify_token(
+        sema: &Semantics<RootDatabase>,
+        token: &SyntaxToken,
+    ) -> Option<IdentClass> {
+        let parent = token.parent()?;
+        // resolve derives if possible
+        if let Some(ident) = ast::Ident::cast(token.clone()) {
+            let attr = ast::TokenTree::cast(parent.clone())
+                .and_then(|tt| tt.parent_meta())
+                .and_then(|meta| meta.parent_attr());
+            if let Some(attr) = attr {
+                return NameRefClass::classify_derive(sema, &attr, &ident)
+                    .map(IdentClass::NameRefClass);
+            }
+        }
+        Self::classify_node(sema, &parent)
+    }
+
+    pub fn definitions(self) -> ArrayVec<Definition, 2> {
+        let mut res = ArrayVec::new();
+        match self {
+            IdentClass::NameClass(NameClass::Definition(it) | NameClass::ConstReference(it)) => {
+                res.push(it)
+            }
+            IdentClass::NameClass(NameClass::PatFieldShorthand { local_def, field_ref }) => {
+                res.push(Definition::Local(local_def));
+                res.push(Definition::Field(field_ref));
+            }
+            IdentClass::NameRefClass(NameRefClass::Definition(it)) => res.push(it),
+            IdentClass::NameRefClass(NameRefClass::FieldShorthand { local_ref, field_ref }) => {
+                res.push(Definition::Local(local_ref));
+                res.push(Definition::Field(field_ref));
+            }
+        }
+        res
+    }
+}
+
 /// On a first blush, a single `ast::Name` defines a single definition at some
 /// scope. That is, that, by just looking at the syntactical category, we can
 /// unambiguously define the semantic category.
@@ -465,6 +456,14 @@ impl NameRefClass {
             _ => None,
         }
     }
+
+    pub fn classify_derive(
+        sema: &Semantics<RootDatabase>,
+        attr: &ast::Attr,
+        ident: &ast::Ident,
+    ) -> Option<NameRefClass> {
+        sema.resolve_derive_ident(&attr, &ident).map(Definition::from).map(NameRefClass::Definition)
+    }
 }
 
 impl_from!(