Rollup merge of #63919 - matthewjasper:remove-gensymmed, r=petrochenkov

Use hygiene for AST passes

AST passes are now able to have resolve consider their expansions as if they were opaque macros defined either in some module in the current crate, or a fake empty module with `#[no_implicit_prelude]`.

* Add an ExpnKind for AST passes.
* Remove gensyms in AST passes.
* Remove gensyms in`#[test]`, `#[bench]` and `#[test_case]`.
* Allow opaque macros to define tests.
* Move tests for unit tests to their own directory.
* Remove `Ident::{gensym, is_gensymed}` - `Ident::gensym_if_underscore` still exists.

cc #60869, #61019

r? @petrochenkov

1 files changed, 13 insertions, 7 deletions

diff --git a/src/libsyntax/ext/base.rs b/src/libsyntax/ext/base.rs
index 109ba041016..5b2515d20cb 100644
--- a/src/libsyntax/ext/base.rs
+++ b/src/libsyntax/ext/base.rs
@@ -3,7 +3,7 @@ use crate::attr::{self, HasAttrs, Stability, Deprecation};
 use crate::source_map::SourceMap;
 use crate::edition::Edition;
 use crate::ext::expand::{self, AstFragment, Invocation};
-use crate::ext::hygiene::{ExpnId, Transparency};
+use crate::ext::hygiene::ExpnId;
 use crate::mut_visit::{self, MutVisitor};
 use crate::parse::{self, parser, ParseSess, DirectoryOwnership};
 use crate::parse::token;
@@ -16,7 +16,7 @@ use crate::visit::Visitor;
 use errors::{DiagnosticBuilder, DiagnosticId};
 use smallvec::{smallvec, SmallVec};
 use syntax_pos::{FileName, Span, MultiSpan, DUMMY_SP};
-use syntax_pos::hygiene::{ExpnData, ExpnKind};
+use syntax_pos::hygiene::{AstPass, ExpnData, ExpnKind};
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sync::{self, Lrc};
@@ -732,13 +732,19 @@ bitflags::bitflags! {
 pub trait Resolver {
     fn next_node_id(&mut self) -> NodeId;
 
-    fn get_module_scope(&mut self, id: NodeId) -> ExpnId;
-
     fn resolve_dollar_crates(&mut self);
     fn visit_ast_fragment_with_placeholders(&mut self, expn_id: ExpnId, fragment: &AstFragment,
                                             extra_placeholders: &[NodeId]);
     fn register_builtin_macro(&mut self, ident: ast::Ident, ext: SyntaxExtension);
 
+    fn expansion_for_ast_pass(
+        &mut self,
+        call_site: Span,
+        pass: AstPass,
+        features: &[Symbol],
+        parent_module_id: Option<NodeId>,
+    ) -> ExpnId;
+
     fn resolve_imports(&mut self);
 
     fn resolve_macro_invocation(
@@ -822,20 +828,20 @@ impl<'a> ExtCtxt<'a> {
     /// Equivalent of `Span::def_site` from the proc macro API,
     /// except that the location is taken from the span passed as an argument.
     pub fn with_def_site_ctxt(&self, span: Span) -> Span {
-        span.with_ctxt_from_mark(self.current_expansion.id, Transparency::Opaque)
+        span.with_def_site_ctxt(self.current_expansion.id)
     }
 
     /// Equivalent of `Span::call_site` from the proc macro API,
     /// except that the location is taken from the span passed as an argument.
     pub fn with_call_site_ctxt(&self, span: Span) -> Span {
-        span.with_ctxt_from_mark(self.current_expansion.id, Transparency::Transparent)
+        span.with_call_site_ctxt(self.current_expansion.id)
     }
 
     /// Span with a context reproducing `macro_rules` hygiene (hygienic locals, unhygienic items).
     /// FIXME: This should be eventually replaced either with `with_def_site_ctxt` (preferably),
     /// or with `with_call_site_ctxt` (where necessary).
     pub fn with_legacy_ctxt(&self, span: Span) -> Span {
-        span.with_ctxt_from_mark(self.current_expansion.id, Transparency::SemiTransparent)
+        span.with_legacy_ctxt(self.current_expansion.id)
     }
 
     /// Returns span for the macro which originally caused the current expansion to happen.