Merge #6599

6599: Add attribute highlight modifier to all tokens inside attributes r=matklad a=Veykril

This has the side effect that we also emit `attribute.attribute` highlights now, as in, the tokens that get the attribute semantic type also get the attribute modifier. I personally don't think it's really a problem but maybe it is to some? It's just that it was really simple to implement it this way, which is why I just went this route for now.

Fixes #6536

Co-authored-by: Lukas Wirth <lukastw97@gmail.com>

crates/ide/src/syntax_highlighting.rs

@@ -76,6 +76,7 @@ pub(crate) fn highlight(
     let mut current_macro_call: Option<ast::MacroCall> = None;
     let mut format_string_highlighter = FormatStringHighlighter::default();
     let mut macro_rules_highlighter = MacroRulesHighlighter::default();
+    let mut inside_attribute = false;
 
     // Walk all nodes, keeping track of whether we are inside a macro or not.
     // If in macro, expand it first and highlight the expanded code.
@@ -132,9 +133,12 @@ pub(crate) fn highlight(
             _ => (),
         }
 
-        // Check for Rust code in documentation
         match &event {
+            // Check for Rust code in documentation
             WalkEvent::Leave(NodeOrToken::Node(node)) => {
+                if ast::Attr::can_cast(node.kind()) {
+                    inside_attribute = false
+                }
                 if let Some((doctest, range_mapping, new_comments)) =
                     injection::extract_doc_comments(node)
                 {
@@ -146,6 +150,9 @@ pub(crate) fn highlight(
                     );
                 }
             }
+            WalkEvent::Enter(NodeOrToken::Node(node)) if ast::Attr::can_cast(node.kind()) => {
+                inside_attribute = true
+            }
             _ => (),
         }
 
@@ -188,12 +195,16 @@ pub(crate) fn highlight(
             }
         }
 
-        if let Some((highlight, binding_hash)) = highlight_element(
+        if let Some((mut highlight, binding_hash)) = highlight_element(
             &sema,
             &mut bindings_shadow_count,
             syntactic_name_ref_highlighting,
             element_to_highlight.clone(),
         ) {
+            if inside_attribute {
+                highlight = highlight | HighlightModifier::Attribute;
+            }
+
             if macro_rules_highlighter.highlight(element_to_highlight.clone()).is_none() {
                 stack.add(HighlightedRange { range, highlight, binding_hash });
             }
@@ -474,7 +485,9 @@ fn highlight_element(
 
         // Highlight references like the definitions they resolve to
         NAME_REF if element.ancestors().any(|it| it.kind() == ATTR) => {
-            Highlight::from(HighlightTag::Function) | HighlightModifier::Attribute
+            // even though we track whether we are in an attribute or not we still need this special case
+            // as otherwise we would emit unresolved references for name refs inside attributes
+            Highlight::from(HighlightTag::Function)
         }
         NAME_REF => {
             let name_ref = element.into_node().and_then(ast::NameRef::cast).unwrap();

crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html

@@ -50,7 +50,7 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="comment documentation">/// # Examples</span>
     <span class="comment documentation">///</span>
     <span class="comment documentation">/// ```</span>
-    <span class="comment documentation">/// #</span><span class="generic injected"> </span><span class="attribute injected">#</span><span class="attribute injected">!</span><span class="attribute injected">[</span><span class="function attribute injected">allow</span><span class="punctuation injected">(</span><span class="attribute injected">unused_mut</span><span class="punctuation injected">)</span><span class="attribute injected">]</span>
+    <span class="comment documentation">/// #</span><span class="generic injected"> </span><span class="attribute attribute injected">#</span><span class="attribute attribute injected">!</span><span class="attribute attribute injected">[</span><span class="function attribute injected">allow</span><span class="punctuation attribute injected">(</span><span class="attribute attribute injected">unused_mut</span><span class="punctuation attribute injected">)</span><span class="attribute attribute injected">]</span>
     <span class="comment documentation">/// </span><span class="keyword injected">let</span><span class="generic injected"> </span><span class="keyword injected">mut</span><span class="generic injected"> </span><span class="variable declaration injected mutable">foo</span><span class="punctuation injected">:</span><span class="generic injected"> </span><span class="struct injected">Foo</span><span class="generic injected"> </span><span class="operator injected">=</span><span class="generic injected"> </span><span class="struct injected">Foo</span><span class="operator injected">::</span><span class="function injected">new</span><span class="punctuation injected">(</span><span class="punctuation injected">)</span><span class="punctuation injected">;</span><span class="punctuation injected">
 </span>    <span class="comment documentation">/// ```</span>
     <span class="keyword">pub</span> <span class="keyword">const</span> <span class="keyword">fn</span> <span class="function declaration static">new</span><span class="punctuation">(</span><span class="punctuation">)</span> <span class="operator">-&gt;</span> <span class="struct">Foo</span> <span class="punctuation">{</span>

crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html

@@ -54,7 +54,7 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 
 <span class="keyword">static</span> <span class="keyword">mut</span> <span class="static declaration mutable unsafe">global_mut</span><span class="punctuation">:</span> <span class="struct">TypeForStaticMut</span> <span class="operator">=</span> <span class="struct">TypeForStaticMut</span> <span class="punctuation">{</span> <span class="field">a</span><span class="punctuation">:</span> <span class="numeric_literal">0</span> <span class="punctuation">}</span><span class="punctuation">;</span>
 
-<span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">repr</span><span class="punctuation">(</span><span class="attribute">packed</span><span class="punctuation">)</span><span class="attribute">]</span>
+<span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">repr</span><span class="punctuation attribute">(</span><span class="attribute attribute">packed</span><span class="punctuation attribute">)</span><span class="attribute attribute">]</span>
 <span class="keyword">struct</span> <span class="struct declaration">Packed</span> <span class="punctuation">{</span>
     <span class="field declaration">a</span><span class="punctuation">:</span> <span class="builtin_type">u16</span><span class="punctuation">,</span>
 <span class="punctuation">}</span>

crates/ide/src/syntax_highlighting/test_data/highlighting.html

@@ -40,18 +40,18 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 
 <span class="comment">// Needed for function consuming vs normal</span>
 <span class="keyword">pub</span> <span class="keyword">mod</span> <span class="module declaration">marker</span> <span class="punctuation">{</span>
-    <span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">lang</span><span class="attribute"> </span><span class="operator">=</span><span class="attribute"> </span><span class="string_literal">"copy"</span><span class="attribute">]</span>
+    <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">lang</span><span class="attribute attribute"> </span><span class="operator attribute">=</span><span class="attribute attribute"> </span><span class="string_literal attribute">"copy"</span><span class="attribute attribute">]</span>
     <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration">Copy</span> <span class="punctuation">{</span><span class="punctuation">}</span>
 <span class="punctuation">}</span>
 
 <span class="keyword">pub</span> <span class="keyword">mod</span> <span class="module declaration">ops</span> <span class="punctuation">{</span>
-    <span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">lang</span><span class="attribute"> </span><span class="operator">=</span><span class="attribute"> </span><span class="string_literal">"fn_once"</span><span class="attribute">]</span>
+    <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">lang</span><span class="attribute attribute"> </span><span class="operator attribute">=</span><span class="attribute attribute"> </span><span class="string_literal attribute">"fn_once"</span><span class="attribute attribute">]</span>
     <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration">FnOnce</span><span class="punctuation">&lt;</span><span class="type_param declaration">Args</span><span class="punctuation">&gt;</span> <span class="punctuation">{</span><span class="punctuation">}</span>
 
-    <span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">lang</span><span class="attribute"> </span><span class="operator">=</span><span class="attribute"> </span><span class="string_literal">"fn_mut"</span><span class="attribute">]</span>
+    <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">lang</span><span class="attribute attribute"> </span><span class="operator attribute">=</span><span class="attribute attribute"> </span><span class="string_literal attribute">"fn_mut"</span><span class="attribute attribute">]</span>
     <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration">FnMut</span><span class="punctuation">&lt;</span><span class="type_param declaration">Args</span><span class="punctuation">&gt;</span><span class="punctuation">:</span> <span class="trait">FnOnce</span><span class="punctuation">&lt;</span><span class="type_param">Args</span><span class="punctuation">&gt;</span> <span class="punctuation">{</span><span class="punctuation">}</span>
 
-    <span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">lang</span><span class="attribute"> </span><span class="operator">=</span><span class="attribute"> </span><span class="string_literal">"fn"</span><span class="attribute">]</span>
+    <span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">lang</span><span class="attribute attribute"> </span><span class="operator attribute">=</span><span class="attribute attribute"> </span><span class="string_literal attribute">"fn"</span><span class="attribute attribute">]</span>
     <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration">Fn</span><span class="punctuation">&lt;</span><span class="type_param declaration">Args</span><span class="punctuation">&gt;</span><span class="punctuation">:</span> <span class="trait">FnMut</span><span class="punctuation">&lt;</span><span class="type_param">Args</span><span class="punctuation">&gt;</span> <span class="punctuation">{</span><span class="punctuation">}</span>
 <span class="punctuation">}</span>
 
@@ -85,7 +85,7 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="punctuation">}</span>
 <span class="punctuation">}</span>
 
-<span class="attribute">#</span><span class="attribute">[</span><span class="function attribute">derive</span><span class="punctuation">(</span><span class="attribute">Copy</span><span class="punctuation">)</span><span class="attribute">]</span>
+<span class="attribute attribute">#</span><span class="attribute attribute">[</span><span class="function attribute">derive</span><span class="punctuation attribute">(</span><span class="attribute attribute">Copy</span><span class="punctuation attribute">)</span><span class="attribute attribute">]</span>
 <span class="keyword">struct</span> <span class="struct declaration">FooCopy</span> <span class="punctuation">{</span>
     <span class="field declaration">x</span><span class="punctuation">:</span> <span class="builtin_type">u32</span><span class="punctuation">,</span>
 <span class="punctuation">}</span>