Merge pull request rust-lang#18410 from Veykril/veykril/push-lvwxpnowqrxk

internal: Invert token iteration order in macro mapping

Author: Veykril

src/tools/rust-analyzer/crates/hir/src/semantics.rs

@@ -945,6 +945,10 @@ impl<'db> SemanticsImpl<'db> {
         };
 
         while let Some((expansion, ref mut tokens)) = stack.pop() {
+            // Reverse the tokens so we prefer first tokens (to accommodate for popping from the
+            // back)
+            // alternatively we could pop from the front but that would shift the content on every pop
+            tokens.reverse();
             while let Some((token, ctx)) = tokens.pop() {
                 let was_not_remapped = (|| {
                     // First expand into attribute invocations

src/tools/rust-analyzer/crates/ide-db/src/lib.rs

@@ -293,3 +293,35 @@ impl SnippetCap {
         }
     }
 }
+
+pub struct Ranker<'a> {
+    pub kind: parser::SyntaxKind,
+    pub text: &'a str,
+    pub ident_kind: bool,
+}
+
+impl<'a> Ranker<'a> {
+    pub const MAX_RANK: usize = 0b1110;
+
+    pub fn from_token(token: &'a syntax::SyntaxToken) -> Self {
+        let kind = token.kind();
+        Ranker { kind, text: token.text(), ident_kind: kind.is_any_identifier() }
+    }
+
+    /// A utility function that ranks a token again a given kind and text, returning a number that
+    /// represents how close the token is to the given kind and text.
+    pub fn rank_token(&self, tok: &syntax::SyntaxToken) -> usize {
+        let tok_kind = tok.kind();
+
+        let exact_same_kind = tok_kind == self.kind;
+        let both_idents = exact_same_kind || (tok_kind.is_any_identifier() && self.ident_kind);
+        let same_text = tok.text() == self.text;
+        // anything that mapped into a token tree has likely no semantic information
+        let no_tt_parent =
+            tok.parent().map_or(false, |it| it.kind() != parser::SyntaxKind::TOKEN_TREE);
+        (both_idents as usize)
+            | ((exact_same_kind as usize) << 1)
+            | ((same_text as usize) << 2)
+            | ((no_tt_parent as usize) << 3)
+    }
+}

src/tools/rust-analyzer/crates/ide/src/call_hierarchy.rs

@@ -510,6 +510,7 @@ fn caller$0() {
             expect![[]],
         );
     }
+
     #[test]
     fn test_call_hierarchy_in_macros_incoming_different_files() {
         check_hierarchy(
@@ -591,9 +592,9 @@ macro_rules! call {
 "#,
             expect!["callee Function FileId(0) 22..37 30..36"],
             expect![[r#"
-                callee Function FileId(0) 38..52 44..50 : FileId(0):44..50
                 caller Function FileId(0) 38..52 : FileId(0):44..50
-                caller Function FileId(1) 130..136 130..136 : FileId(0):44..50"#]],
+                caller Function FileId(1) 130..136 130..136 : FileId(0):44..50
+                callee Function FileId(0) 38..52 44..50 : FileId(0):44..50"#]],
             expect![[]],
         );
     }

src/tools/rust-analyzer/crates/ide/src/hover.rs

@@ -11,7 +11,7 @@ use ide_db::{
     defs::{Definition, IdentClass, NameRefClass, OperatorClass},
     famous_defs::FamousDefs,
     helpers::pick_best_token,
-    FileRange, FxIndexSet, RootDatabase,
+    FileRange, FxIndexSet, Ranker, RootDatabase,
 };
 use itertools::{multizip, Itertools};
 use span::Edition;
@@ -182,27 +182,13 @@ fn hover_offset(
     // equivalency is more important
     let mut descended = sema.descend_into_macros(original_token.clone());
 
-    let kind = original_token.kind();
-    let text = original_token.text();
-    let ident_kind = kind.is_any_identifier();
-
-    descended.sort_by_cached_key(|tok| {
-        let tok_kind = tok.kind();
-
-        let exact_same_kind = tok_kind == kind;
-        let both_idents = exact_same_kind || (tok_kind.is_any_identifier() && ident_kind);
-        let same_text = tok.text() == text;
-        // anything that mapped into a token tree has likely no semantic information
-        let no_tt_parent = tok.parent().map_or(false, |it| it.kind() != TOKEN_TREE);
-        !((both_idents as usize)
-            | ((exact_same_kind as usize) << 1)
-            | ((same_text as usize) << 2)
-            | ((no_tt_parent as usize) << 3))
-    });
+    let ranker = Ranker::from_token(&original_token);
+
+    descended.sort_by_cached_key(|tok| !ranker.rank_token(tok));
 
     let mut res = vec![];
     for token in descended {
-        let is_same_kind = token.kind() == kind;
+        let is_same_kind = token.kind() == ranker.kind;
         let lint_hover = (|| {
             // FIXME: Definition should include known lints and the like instead of having this special case here
             let attr = token.parent_ancestors().find_map(ast::Attr::cast)?;

src/tools/rust-analyzer/crates/ide/src/hover/tests.rs

@@ -289,7 +289,7 @@ m!(ab$0c);
             *abc*
 
             ```rust
-            test::module
+            test
             ```
 
             ```rust
@@ -298,11 +298,11 @@ m!(ab$0c);
 
             ---
 
-            Inner
+            Outer
             ---
 
             ```rust
-            test
+            test::module
             ```
 
             ```rust
@@ -311,7 +311,7 @@ m!(ab$0c);
 
             ---
 
-            Outer
+            Inner
         "#]],
     );
 }

src/tools/rust-analyzer/crates/ide/src/references.rs

@@ -1701,14 +1701,14 @@ fn f() {
 }
             "#,
             expect![[r#"
-                func Function FileId(0) 137..146 140..144
+                func Function FileId(0) 137..146 140..144 module
 
-                FileId(0) 161..165
+                FileId(0) 181..185
 
 
-                func Function FileId(0) 137..146 140..144 module
+                func Function FileId(0) 137..146 140..144
 
-                FileId(0) 181..185
+                FileId(0) 161..165
             "#]],
         )
     }

src/tools/rust-analyzer/crates/ide/src/syntax_highlighting.rs

@@ -16,7 +16,7 @@ mod tests;
 use std::ops::ControlFlow;
 
 use hir::{InRealFile, Name, Semantics};
-use ide_db::{FxHashMap, RootDatabase, SymbolKind};
+use ide_db::{FxHashMap, Ranker, RootDatabase, SymbolKind};
 use span::EditionedFileId;
 use syntax::{
     ast::{self, IsString},
@@ -397,13 +397,12 @@ fn traverse(
                 Some(AttrOrDerive::Derive(_)) => inside_attribute,
                 None => false,
             };
+
         let descended_element = if in_macro {
             // Attempt to descend tokens into macro-calls.
             let res = match element {
                 NodeOrToken::Token(token) if token.kind() != COMMENT => {
-                    let kind = token.kind();
-                    let text = token.text();
-                    let ident_kind = kind.is_any_identifier();
+                    let ranker = Ranker::from_token(&token);
 
                     let mut t = None;
                     let mut r = 0;
@@ -412,21 +411,9 @@ fn traverse(
                         |tok, _ctx| {
                             // FIXME: Consider checking ctx transparency for being opaque?
                             let tok = tok.value;
-                            let tok_kind = tok.kind();
-
-                            let exact_same_kind = tok_kind == kind;
-                            let both_idents =
-                                exact_same_kind || (tok_kind.is_any_identifier() && ident_kind);
-                            let same_text = tok.text() == text;
-                            // anything that mapped into a token tree has likely no semantic information
-                            let no_tt_parent =
-                                tok.parent().map_or(false, |it| it.kind() != TOKEN_TREE);
-                            let my_rank = (both_idents as usize)
-                                | ((exact_same_kind as usize) << 1)
-                                | ((same_text as usize) << 2)
-                                | ((no_tt_parent as usize) << 3);
-
-                            if my_rank > 0b1110 {
+                            let my_rank = ranker.rank_token(&tok);
+
+                            if my_rank >= Ranker::MAX_RANK {
                                 // a rank of 0b1110 means that we have found a maximally interesting
                                 // token so stop early.
                                 t = Some(tok);

src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_issue_18089.html

@@ -50,4 +50,4 @@
 <span class="brace">}</span>
 
 <span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="module attribute crate_root library">proc_macros</span><span class="operator attribute">::</span><span class="attribute attribute library">issue_18089</span><span class="attribute_bracket attribute">]</span>
-<span class="keyword">fn</span> <span class="function declaration">template</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span><span class="brace">}</span></code></pre>
+<span class="keyword">fn</span> <span class="macro declaration">template</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span><span class="brace">}</span></code></pre>