Add highlights for input /commands and @file/paths (#7165)

packages/cli/src/ui/utils/highlight.ts

@@ -0,0 +1,56 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+export type HighlightToken = {
+  text: string;
+  type: 'default' | 'command' | 'file';
+};
+
+const HIGHLIGHT_REGEX = /(\/[a-zA-Z0-9_-]+|@[a-zA-Z0-9_./-]+)/g;
+
+export function parseInputForHighlighting(
+  text: string,
+): readonly HighlightToken[] {
+  if (!text) {
+    return [{ text: '', type: 'default' }];
+  }
+
+  const tokens: HighlightToken[] = [];
+  let lastIndex = 0;
+  let match;
+
+  while ((match = HIGHLIGHT_REGEX.exec(text)) !== null) {
+    const [fullMatch] = match;
+    const matchIndex = match.index;
+
+    // Add the text before the match as a default token
+    if (matchIndex > lastIndex) {
+      tokens.push({
+        text: text.slice(lastIndex, matchIndex),
+        type: 'default',
+      });
+    }
+
+    // Add the matched token
+    const type = fullMatch.startsWith('/') ? 'command' : 'file';
+    tokens.push({
+      text: fullMatch,
+      type,
+    });
+
+    lastIndex = matchIndex + fullMatch.length;
+  }
+
+  // Add any remaining text after the last match
+  if (lastIndex < text.length) {
+    tokens.push({
+      text: text.slice(lastIndex),
+      type: 'default',
+    });
+  }
+
+  return tokens;
+}