feat: 新增 tryGet

src/index.ts

@@ -51,6 +51,7 @@ export * from './startsWith'
 export * from './sum'
 export * from './throttle'
 export * from './times'
+export * from './tryGet'
 export * from './unique'
 export * from './URI'
 export * from './values'

src/tryGet.test.ts

@@ -0,0 +1,39 @@
+import { jestExpectEqual } from './enhanceJest'
+import { tryGet } from './tryGet'
+
+const obj = {
+  x: 1,
+  s: '字符串',
+  y: {
+    yy: {
+      yyyy: {
+        yyyyy: () => 'hello',
+        yyyyy2: true,
+      },
+      yyyy2: [0, 1, 2, 3],
+      yyyy3: /.+/,
+    },
+  },
+  z: {
+    zz: null,
+    zzz: undefined,
+    zzzz: 'hoho',
+  },
+}
+
+test('表现正常', () => {
+  jestExpectEqual(
+    tryGet(() => obj.y.yy),
+    obj.y.yy,
+  )
+
+  jestExpectEqual(
+    tryGet(() => (obj as any).y.yy.xxx.ffs),
+    undefined,
+  )
+
+  jestExpectEqual(
+    tryGet(() => (obj as any).y.yy.xxx.ffs, 1),
+    1,
+  )
+})

src/tryGet.ts

@@ -0,0 +1,42 @@
+export interface TryGetAccessor<R> {
+  (): R,
+}
+
+/**
+ * 尝试执行 `accessor` 返回值，若其报错，返回默认值 `defaultValue`。
+ *
+ * @param accessor 值获取器
+ * @param defaultValue 默认值
+ * @returns 返回结果值
+ * @example
+ * ```ts
+ * const obj = { x: 1 }
+ * tryGet(() => obj.x, 2) // => 1
+ * tryGet(() => obj.x.y, 2) // => 2
+ * ```
+ */
+export function tryGet<R>(accessor: TryGetAccessor<R>, defaultValue: R): R
+
+/**
+ * 尝试执行 `accessor` 返回值，若其报错，返回 `undefined`。
+ *
+ * @param accessor 值获取器
+ * @returns 返回结果值
+ * @example
+ * ```ts
+ * const obj = { x: 1 }
+ * tryGet(() => obj.x) // => 1
+ * tryGet(() => obj.x.y) // => undefined
+ * ```
+ */
+export function tryGet<R>(accessor: TryGetAccessor<R>): R | undefined
+
+export function tryGet<R>(accessor: TryGetAccessor<R>, defaultValue?: R): R | undefined {
+  let result: R | undefined
+  try {
+    result = accessor()
+  } catch (e) {
+    result = defaultValue
+  }
+  return result
+}