Auto merge of rust-lang#17799 - Veykril:syntax-bridge, r=Veykril

Split out syntax-bridge into a separate crate

This functionality is not really tied to mbe macros, so imo it has no place in that crate.

Cargo.toml

@@ -77,6 +77,7 @@ salsa = { path = "./crates/salsa", version = "0.0.0" }
 span = { path = "./crates/span", version = "0.0.0" }
 stdx = { path = "./crates/stdx", version = "0.0.0" }
 syntax = { path = "./crates/syntax", version = "0.0.0" }
+syntax-bridge = { path = "./crates/syntax-bridge", version = "0.0.0" }
 text-edit = { path = "./crates/text-edit", version = "0.0.0" }
 toolchain = { path = "./crates/toolchain", version = "0.0.0" }
 tt = { path = "./crates/tt", version = "0.0.0" }

crates/cfg/Cargo.toml

@@ -28,7 +28,7 @@ arbitrary = "1.3.2"
 derive_arbitrary = "1.3.2"
 
 # local deps
-mbe.workspace = true
+syntax-bridge.workspace = true
 syntax.workspace = true
 
 [lints]

crates/cfg/src/tests.rs

@@ -1,8 +1,11 @@
 use arbitrary::{Arbitrary, Unstructured};
 use expect_test::{expect, Expect};
 use intern::Symbol;
-use mbe::{syntax_node_to_token_tree, DocCommentDesugarMode, DummyTestSpanMap, DUMMY};
 use syntax::{ast, AstNode, Edition};
+use syntax_bridge::{
+    dummy_test_span_utils::{DummyTestSpanMap, DUMMY},
+    syntax_node_to_token_tree, DocCommentDesugarMode,
+};
 
 use crate::{CfgAtom, CfgExpr, CfgOptions, DnfExpr};
 

crates/hir-def/Cargo.toml

@@ -52,7 +52,7 @@ expect-test.workspace = true
 # local deps
 test-utils.workspace = true
 test-fixture.workspace = true
-
+syntax-bridge.workspace = true
 [features]
 in-rust-tree = ["hir-expand/in-rust-tree"]
 

crates/hir-def/src/attr.rs

@@ -657,9 +657,9 @@ mod tests {
     use triomphe::Arc;
 
     use hir_expand::span_map::{RealSpanMap, SpanMap};
-    use mbe::{syntax_node_to_token_tree, DocCommentDesugarMode};
     use span::FileId;
     use syntax::{ast, AstNode, TextRange};
+    use syntax_bridge::{syntax_node_to_token_tree, DocCommentDesugarMode};
 
     use crate::attr::{DocAtom, DocExpr};
 

crates/hir-def/src/macro_expansion_tests/mbe.rs

@@ -1201,7 +1201,6 @@ macro_rules! m {
 
 #[test]
 fn test_meta_doc_comments() {
-    cov_mark::check!(test_meta_doc_comments);
     check(
         r#"
 macro_rules! m {

crates/hir-def/src/macro_expansion_tests/mod.rs

@@ -317,9 +317,9 @@ impl ProcMacroExpander for IdentityWhenValidProcMacroExpander {
         _: Span,
         _: Span,
     ) -> Result<Subtree, ProcMacroExpansionError> {
-        let (parse, _) = ::mbe::token_tree_to_syntax_node(
+        let (parse, _) = syntax_bridge::token_tree_to_syntax_node(
             subtree,
-            ::mbe::TopEntryPoint::MacroItems,
+            syntax_bridge::TopEntryPoint::MacroItems,
             span::Edition::CURRENT,
         );
         if parse.errors().is_empty() {

crates/hir-expand/Cargo.toml

@@ -33,6 +33,7 @@ mbe.workspace = true
 limit.workspace = true
 span.workspace = true
 parser.workspace = true
+syntax-bridge.workspace = true
 
 [dev-dependencies]
 expect-test = "1.4.0"

crates/hir-expand/src/attrs.rs

@@ -6,14 +6,12 @@ use cfg::CfgExpr;
 use either::Either;
 use intern::{sym, Interned, Symbol};
 
-use mbe::{
-    desugar_doc_comment_text, syntax_node_to_token_tree, DelimiterKind, DocCommentDesugarMode,
-    Punct,
-};
+use mbe::{DelimiterKind, Punct};
 use smallvec::{smallvec, SmallVec};
 use span::{Span, SyntaxContextId};
 use syntax::unescape;
 use syntax::{ast, match_ast, AstNode, AstToken, SyntaxNode};
+use syntax_bridge::{desugar_doc_comment_text, syntax_node_to_token_tree, DocCommentDesugarMode};
 use triomphe::ThinArc;
 
 use crate::name::Name;

crates/hir-expand/src/builtin/derive_macro.rs

@@ -2,10 +2,10 @@
 
 use intern::sym;
 use itertools::izip;
-use mbe::DocCommentDesugarMode;
 use rustc_hash::FxHashSet;
 use span::{MacroCallId, Span};
 use stdx::never;
+use syntax_bridge::DocCommentDesugarMode;
 use tracing::debug;
 
 use crate::{
@@ -209,9 +209,9 @@ struct BasicAdtInfo {
 }
 
 fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandError> {
-    let (parsed, tm) = &mbe::token_tree_to_syntax_node(
+    let (parsed, tm) = &syntax_bridge::token_tree_to_syntax_node(
         tt,
-        mbe::TopEntryPoint::MacroItems,
+        syntax_bridge::TopEntryPoint::MacroItems,
         parser::Edition::CURRENT_FIXME,
     );
     let macro_items = ast::MacroItems::cast(parsed.syntax_node())
@@ -268,7 +268,7 @@ fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandEr
                 match this {
                     Some(it) => {
                         param_type_set.insert(it.as_name());
-                        mbe::syntax_node_to_token_tree(
+                        syntax_bridge::syntax_node_to_token_tree(
                             it.syntax(),
                             tm,
                             call_site,
@@ -282,7 +282,7 @@ fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandEr
             };
             let bounds = match &param {
                 ast::TypeOrConstParam::Type(it) => it.type_bound_list().map(|it| {
-                    mbe::syntax_node_to_token_tree(
+                    syntax_bridge::syntax_node_to_token_tree(
                         it.syntax(),
                         tm,
                         call_site,
@@ -295,7 +295,7 @@ fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandEr
                 let ty = param
                     .ty()
                     .map(|ty| {
-                        mbe::syntax_node_to_token_tree(
+                        syntax_bridge::syntax_node_to_token_tree(
                             ty.syntax(),
                             tm,
                             call_site,
@@ -316,7 +316,7 @@ fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandEr
     let where_clause = if let Some(w) = where_clause {
         w.predicates()
             .map(|it| {
-                mbe::syntax_node_to_token_tree(
+                syntax_bridge::syntax_node_to_token_tree(
                     it.syntax(),
                     tm,
                     call_site,
@@ -353,7 +353,7 @@ fn parse_adt(tt: &tt::Subtree, call_site: Span) -> Result<BasicAdtInfo, ExpandEr
             param_type_set.contains(&name).then_some(p)
         })
         .map(|it| {
-            mbe::syntax_node_to_token_tree(
+            syntax_bridge::syntax_node_to_token_tree(
                 it.syntax(),
                 tm,
                 call_site,

crates/hir-expand/src/builtin/fn_macro.rs

@@ -4,13 +4,14 @@ use base_db::AnchoredPath;
 use cfg::CfgExpr;
 use either::Either;
 use intern::{sym, Symbol};
-use mbe::{parse_exprs_with_sep, parse_to_token_tree, DelimiterKind};
+use mbe::{expect_fragment, DelimiterKind};
 use span::{Edition, EditionedFileId, Span, SpanAnchor, SyntaxContextId, ROOT_ERASED_FILE_AST_ID};
 use stdx::format_to;
 use syntax::{
     format_smolstr,
     unescape::{unescape_byte, unescape_char, unescape_unicode, Mode},
 };
+use syntax_bridge::parse_to_token_tree;
 
 use crate::{
     builtin::quote::{dollar_crate, quote},
@@ -228,20 +229,22 @@ fn assert_expand(
     span: Span,
 ) -> ExpandResult<tt::Subtree> {
     let call_site_span = span_with_call_site_ctxt(db, span, id);
-    let args = parse_exprs_with_sep(tt, ',', call_site_span, Edition::CURRENT_FIXME);
+
+    let mut iter = ::tt::iter::TtIter::new(tt);
+
+    let cond = expect_fragment(
+        &mut iter,
+        parser::PrefixEntryPoint::Expr,
+        db.crate_graph()[id.lookup(db).krate].edition,
+        tt::DelimSpan { open: tt.delimiter.open, close: tt.delimiter.close },
+    );
+    _ = iter.expect_char(',');
+    let rest = iter.as_slice();
+
     let dollar_crate = dollar_crate(span);
-    let expanded = match &*args {
-        [cond, panic_args @ ..] => {
-            let comma = tt::Subtree {
-                delimiter: tt::Delimiter::invisible_spanned(call_site_span),
-                token_trees: Box::new([tt::TokenTree::Leaf(tt::Leaf::Punct(tt::Punct {
-                    char: ',',
-                    spacing: tt::Spacing::Alone,
-                    span: call_site_span,
-                }))]),
-            };
-            let cond = cond.clone();
-            let panic_args = itertools::Itertools::intersperse(panic_args.iter().cloned(), comma);
+    let expanded = match cond.value {
+        Some(cond) => {
+            let panic_args = rest.iter().cloned();
             let mac = if use_panic_2021(db, span) {
                 quote! {call_site_span => #dollar_crate::panic::panic_2021!(##panic_args) }
             } else {
@@ -253,10 +256,13 @@ fn assert_expand(
                 }
             }}
         }
-        [] => quote! {call_site_span =>{}},
+        None => quote! {call_site_span =>{}},
     };
 
-    ExpandResult::ok(expanded)
+    match cond.err {
+        Some(err) => ExpandResult::new(expanded, err.into()),
+        None => ExpandResult::ok(expanded),
+    }
 }
 
 fn file_expand(

crates/hir-expand/src/db.rs

@@ -3,10 +3,11 @@
 use base_db::{salsa, CrateId, SourceDatabase};
 use either::Either;
 use limit::Limit;
-use mbe::{syntax_node_to_token_tree, DocCommentDesugarMode, MatchedArmIndex};
+use mbe::MatchedArmIndex;
 use rustc_hash::FxHashSet;
 use span::{AstIdMap, EditionedFileId, Span, SyntaxContextData, SyntaxContextId};
 use syntax::{ast, AstNode, Parse, SyntaxElement, SyntaxError, SyntaxNode, SyntaxToken, T};
+use syntax_bridge::{syntax_node_to_token_tree, DocCommentDesugarMode};
 use triomphe::Arc;
 
 use crate::{
@@ -165,7 +166,7 @@ pub fn expand_speculative(
     // Build the subtree and token mapping for the speculative args
     let (mut tt, undo_info) = match loc.kind {
         MacroCallKind::FnLike { .. } => (
-            mbe::syntax_node_to_token_tree(
+            syntax_bridge::syntax_node_to_token_tree(
                 speculative_args,
                 span_map,
                 span,
@@ -178,7 +179,7 @@ pub fn expand_speculative(
             SyntaxFixupUndoInfo::NONE,
         ),
         MacroCallKind::Attr { .. } if loc.def.is_attribute_derive() => (
-            mbe::syntax_node_to_token_tree(
+            syntax_bridge::syntax_node_to_token_tree(
                 speculative_args,
                 span_map,
                 span,
@@ -213,7 +214,7 @@ pub fn expand_speculative(
             fixups.remove.extend(censor_cfg);
 
             (
-                mbe::syntax_node_to_token_tree_modified(
+                syntax_bridge::syntax_node_to_token_tree_modified(
                     speculative_args,
                     span_map,
                     fixups.append,
@@ -459,7 +460,7 @@ fn macro_arg(db: &dyn ExpandDatabase, id: MacroCallId) -> MacroArgResult {
                 return dummy_tt(kind);
             }
 
-            let mut tt = mbe::syntax_node_to_token_tree(
+            let mut tt = syntax_bridge::syntax_node_to_token_tree(
                 tt.syntax(),
                 map.as_ref(),
                 span,
@@ -515,7 +516,7 @@ fn macro_arg(db: &dyn ExpandDatabase, id: MacroCallId) -> MacroArgResult {
         fixups.remove.extend(censor_cfg);
 
         (
-            mbe::syntax_node_to_token_tree_modified(
+            syntax_bridge::syntax_node_to_token_tree_modified(
                 syntax,
                 map,
                 fixups.append,
@@ -720,13 +721,13 @@ fn token_tree_to_syntax_node(
     edition: parser::Edition,
 ) -> (Parse<SyntaxNode>, ExpansionSpanMap) {
     let entry_point = match expand_to {
-        ExpandTo::Statements => mbe::TopEntryPoint::MacroStmts,
-        ExpandTo::Items => mbe::TopEntryPoint::MacroItems,
-        ExpandTo::Pattern => mbe::TopEntryPoint::Pattern,
-        ExpandTo::Type => mbe::TopEntryPoint::Type,
-        ExpandTo::Expr => mbe::TopEntryPoint::Expr,
+        ExpandTo::Statements => syntax_bridge::TopEntryPoint::MacroStmts,
+        ExpandTo::Items => syntax_bridge::TopEntryPoint::MacroItems,
+        ExpandTo::Pattern => syntax_bridge::TopEntryPoint::Pattern,
+        ExpandTo::Type => syntax_bridge::TopEntryPoint::Type,
+        ExpandTo::Expr => syntax_bridge::TopEntryPoint::Expr,
     };
-    mbe::token_tree_to_syntax_node(tt, entry_point, edition)
+    syntax_bridge::token_tree_to_syntax_node(tt, entry_point, edition)
 }
 
 fn check_tt_count(tt: &tt::Subtree) -> Result<(), ExpandResult<()>> {