Add static semantic token modifier for associated functions with no &self

crates/ide/src/syntax_highlighting.rs

@@ -746,6 +746,21 @@ fn highlight_def(db: &RootDatabase, def: Definition) -> Highlight {
                 if func.is_unsafe(db) {
                     h |= HighlightModifier::Unsafe;
                 }
+                if let None = func.self_param(db) {
+                    // if enclosing IMPL or TRAIT exists, this is a static method
+                    let fn_parent_kind = func
+                        .source(db)
+                        .value
+                        .syntax()
+                        .parent()
+                        .and_then(|s| s.parent())
+                        .and_then(|s| Some(s.kind()));
+                    if let Some(SyntaxKind::IMPL) = fn_parent_kind {
+                        h |= HighlightModifier::Static;
+                    } else if let Some(SyntaxKind::TRAIT) = fn_parent_kind {
+                        h |= HighlightModifier::Static;
+                    }
+                }
                 return h;
             }
             hir::ModuleDef::Adt(hir::Adt::Struct(_)) => HighlightTag::Struct,