Add a mirror function-like proc-macro expander for tests

crates/base_db/src/fixture.rs

@@ -262,6 +262,10 @@ pub fn identity(_attr: TokenStream, item: TokenStream) -> TokenStream {
 pub fn input_replace(attr: TokenStream, _item: TokenStream) -> TokenStream {
     attr
 }
+#[proc_macro]
+pub fn mirror(input: TokenStream) -> TokenStream {
+    input
+}
 "#;
     let proc_macros = std::array::IntoIter::new([
         ProcMacro {
@@ -274,6 +278,11 @@ pub fn input_replace(attr: TokenStream, _item: TokenStream) -> TokenStream {
             kind: crate::ProcMacroKind::Attr,
             expander: Arc::new(AttributeInputReplaceProcMacroExpander),
         },
+        ProcMacro {
+            name: "mirror".into(),
+            kind: crate::ProcMacroKind::FuncLike,
+            expander: Arc::new(MirrorProcMacroExpander),
+        },
     ])
     .filter(|pm| proc_macros.iter().any(|name| name == pm.name))
     .collect();
@@ -348,3 +357,28 @@ fn expand(
             .ok_or_else(|| ProcMacroExpansionError::Panic("Expected attribute input".into()))
     }
 }
+
+#[derive(Debug)]
+struct MirrorProcMacroExpander;
+impl ProcMacroExpander for MirrorProcMacroExpander {
+    fn expand(
+        &self,
+        input: &Subtree,
+        _: Option<&Subtree>,
+        _: &Env,
+    ) -> Result<Subtree, ProcMacroExpansionError> {
+        fn traverse(input: &Subtree) -> Subtree {
+            let mut res = Subtree::default();
+            res.delimiter = input.delimiter;
+            for tt in input.token_trees.iter().rev() {
+                let tt = match tt {
+                    tt::TokenTree::Leaf(leaf) => tt::TokenTree::Leaf(leaf.clone()),
+                    tt::TokenTree::Subtree(sub) => tt::TokenTree::Subtree(traverse(sub)),
+                };
+                res.token_trees.push(tt);
+            }
+            res
+        }
+        Ok(traverse(input))
+    }
+}

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

@@ -64,10 +64,11 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="keyword">pub</span> <span class="keyword">trait</span> <span class="trait declaration public">Fn</span><span class="angle">&lt;</span><span class="type_param declaration">Args</span><span class="angle">&gt;</span><span class="colon">:</span> <span class="trait public">FnMut</span><span class="angle">&lt;</span><span class="type_param">Args</span><span class="angle">&gt;</span> <span class="brace">{</span><span class="brace">}</span>
 <span class="brace">}</span>
 
-
-<span class="keyword">struct</span> <span class="struct declaration">Foo</span> <span class="brace">{</span>
-    <span class="keyword">pub</span> <span class="field declaration public">x</span><span class="colon">:</span> <span class="builtin_type">i32</span><span class="comma">,</span>
-    <span class="keyword">pub</span> <span class="field declaration public">y</span><span class="colon">:</span> <span class="builtin_type">i32</span><span class="comma">,</span>
+proc_macros::<span class="macro">mirror!</span> <span class="brace">{</span>
+    <span class="brace">{</span>
+        <span class="comma">,</span><span class="builtin_type">i32</span> <span class="colon">:</span><span class="field declaration public">x</span> <span class="keyword">pub</span>
+        <span class="comma">,</span><span class="builtin_type">i32</span> <span class="colon">:</span><span class="field declaration public">y</span> <span class="keyword">pub</span>
+    <span class="brace">}</span> <span class="struct declaration">Foo</span> <span class="keyword">struct</span>
 <span class="brace">}</span>
 
 <span class="keyword">trait</span> <span class="trait declaration">Bar</span> <span class="keyword">where</span> <span class="type_param">Self</span><span class="colon">:</span> <span class="brace">{</span>

crates/ide/src/syntax_highlighting/tests.rs

@@ -10,7 +10,7 @@
 fn test_highlighting() {
     check_highlighting(
         r#"
-//- proc_macros: identity
+//- proc_macros: identity, mirror
 //- /main.rs crate:main deps:foo
 use inner::{self as inner_mod};
 mod inner {}
@@ -36,10 +36,11 @@ pub trait FnMut<Args>: FnOnce<Args> {}
     pub trait Fn<Args>: FnMut<Args> {}
 }
 
-
-struct Foo {
-    pub x: i32,
-    pub y: i32,
+proc_macros::mirror! {
+    {
+        ,i32 :x pub
+        ,i32 :y pub
+    } Foo struct
 }
 
 trait Bar where Self: {

crates/ide_assists/src/handlers/convert_iter_for_each_to_for.rs

@@ -32,7 +32,6 @@
 //     }
 // }
 // ```
-
 pub(crate) fn convert_iter_for_each_to_for(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
     let method = ctx.find_node_at_offset::<ast::MethodCallExpr>()?;