Sync upstream Gemini-CLI v0.8.2 (#838)

packages/cli/src/utils/deepMerge.ts

@@ -0,0 +1,90 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { MergeStrategy } from '../config/settingsSchema.js';
+
+export type Mergeable =
+  | string
+  | number
+  | boolean
+  | null
+  | undefined
+  | object
+  | Mergeable[];
+
+export type MergeableObject = Record<string, Mergeable>;
+
+function isPlainObject(item: unknown): item is MergeableObject {
+  return !!item && typeof item === 'object' && !Array.isArray(item);
+}
+
+function mergeRecursively(
+  target: MergeableObject,
+  source: MergeableObject,
+  getMergeStrategyForPath: (path: string[]) => MergeStrategy | undefined,
+  path: string[] = [],
+) {
+  for (const key of Object.keys(source)) {
+    if (key === '__proto__' || key === 'constructor' || key === 'prototype') {
+      continue;
+    }
+    const newPath = [...path, key];
+    const srcValue = source[key];
+    const objValue = target[key];
+    const mergeStrategy = getMergeStrategyForPath(newPath);
+
+    if (mergeStrategy === MergeStrategy.SHALLOW_MERGE && objValue && srcValue) {
+      const obj1 =
+        typeof objValue === 'object' && objValue !== null ? objValue : {};
+      const obj2 =
+        typeof srcValue === 'object' && srcValue !== null ? srcValue : {};
+      target[key] = { ...obj1, ...obj2 };
+      continue;
+    }
+
+    if (Array.isArray(objValue)) {
+      const srcArray = Array.isArray(srcValue) ? srcValue : [srcValue];
+      if (mergeStrategy === MergeStrategy.CONCAT) {
+        target[key] = objValue.concat(srcArray);
+        continue;
+      }
+      if (mergeStrategy === MergeStrategy.UNION) {
+        target[key] = [...new Set(objValue.concat(srcArray))];
+        continue;
+      }
+    }
+
+    if (isPlainObject(objValue) && isPlainObject(srcValue)) {
+      mergeRecursively(objValue, srcValue, getMergeStrategyForPath, newPath);
+    } else if (isPlainObject(srcValue)) {
+      target[key] = {};
+      mergeRecursively(
+        target[key] as MergeableObject,
+        srcValue,
+        getMergeStrategyForPath,
+        newPath,
+      );
+    } else {
+      target[key] = srcValue;
+    }
+  }
+  return target;
+}
+
+export function customDeepMerge(
+  getMergeStrategyForPath: (path: string[]) => MergeStrategy | undefined,
+  ...sources: MergeableObject[]
+): MergeableObject {
+  const result: MergeableObject = {};
+
+  for (const source of sources) {
+    if (source) {
+      mergeRecursively(result, source, getMergeStrategyForPath);
+    }
+  }
+
+  return result;
+}