Merge #4654

4654: Add semantic highlight to ? operator r=matklad a=ruabmbua

Made it an operator with controlFlow modifier.

To highlight in vscode as red:

```json
"editor.semanticTokenColorCustomizations": {
        "enabled": true,
        "rules": {
            "operator.controlFlow": "#ff0000",
        }
}
```

![Bildschirmfoto von 2020-05-29 21-32-06](https://user-images.githubusercontent.com/2522373/83297998-f3585a00-a1f3-11ea-9d14-4ef04b9b6b9a.png)

https://github.com/rust-analyzer/rust-analyzer/issues/4597


Co-authored-by: Roland Ruckerbauer <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/crates/ra_ide/src/syntax_highlighting/tags.rs b/crates/ra_ide/src/syntax_highlighting/tags.rs
index 46c718c91..1514531de 100644
--- a/crates/ra_ide/src/syntax_highlighting/tags.rs
+++ b/crates/ra_ide/src/syntax_highlighting/tags.rs
@@ -42,6 +42,7 @@ pub enum HighlightTag {
     Local,
     UnresolvedReference,
     FormatSpecifier,
+    Operator,
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
@@ -89,6 +90,7 @@ impl HighlightTag {
             HighlightTag::Local => "variable",
             HighlightTag::UnresolvedReference => "unresolved_reference",
             HighlightTag::FormatSpecifier => "format_specifier",
+            HighlightTag::Operator => "operator",
         }
     }
 }