Fixes #23460

npm-shrinkwrap.json

@@ -420,9 +420,9 @@
       "resolved": "https://registry.npmjs.org/vscode-ripgrep/-/vscode-ripgrep-0.0.11.tgz"
     },
     "vscode-textmate": {
-      "version": "3.1.2",
-      "from": "vscode-textmate@3.1.2",
-      "resolved": "https://registry.npmjs.org/vscode-textmate/-/vscode-textmate-3.1.2.tgz"
+      "version": "3.1.3",
+      "from": "vscode-textmate@3.1.3",
+      "resolved": "https://registry.npmjs.org/vscode-textmate/-/vscode-textmate-3.1.3.tgz"
     },
     "windows-foreground-love": {
       "version": "0.1.0",

package.json

@@ -37,7 +37,7 @@
     "v8-profiler": "jrieken/v8-profiler#vscode",
     "vscode-debugprotocol": "1.18.0",
     "vscode-ripgrep": "0.0.11",
-    "vscode-textmate": "^3.1.2",
+    "vscode-textmate": "^3.1.3",
     "winreg": "1.2.0",
     "xterm": "Tyriar/xterm.js#vscode-release/1.11",
     "yauzl": "2.3.1"

src/vs/editor/electron-browser/textMate/TMHelper.ts

@@ -71,14 +71,40 @@ export class ThemeRule {
 		return ThemeRule._matches(this.scope, this.parentScopes, scope, parentScopes);
 	}
 
+	private static _cmp(a: ThemeRule, b: ThemeRule): number {
+		if (a === null && b === null) {
+			return 0;
+		}
+		if (a === null) {
+			// b > a
+			return -1;
+		}
+		if (b === null) {
+			// a > b
+			return 1;
+		}
+		if (a.scope.length !== b.scope.length) {
+			// longer scope length > shorter scope length
+			return a.scope.length - b.scope.length;
+		}
+		const aParentScopesLen = a.parentScopes.length;
+		const bParentScopesLen = b.parentScopes.length;
+		if (aParentScopesLen !== bParentScopesLen) {
+			// more parents > less parents
+			return aParentScopesLen - bParentScopesLen;
+		}
+		for (let i = 0; i < aParentScopesLen; i++) {
+			var aLen = a.parentScopes[i].length;
+			var bLen = b.parentScopes[i].length;
+			if (aLen !== bLen) {
+				return aLen - bLen;
+			}
+		}
+		return 0;
+	}
+
 	public isMoreSpecific(other: ThemeRule): boolean {
-		if (other === null) {
-			return true;
-		}
-		if (other.scope.length === this.scope.length) {
-			return this.parentScopes.length > other.parentScopes.length;
-		}
-		return (this.scope.length > other.scope.length);
+		return (ThemeRule._cmp(this, other) > 0);
 	}
 
 	private static _matchesOne(selectorScope: string, scope: string): boolean {