feat: 新增 safeGet

src/index.ts

@@ -42,6 +42,7 @@ export * from './randomString'
 export * from './range'
 export * from './repeat'
 export * from './round'
+export * from './safeGet'
 export * from './sample'
 export * from './sequential'
 export * from './shuffle'

src/safeGet.test.ts

@@ -0,0 +1,69 @@
+import { jestExpectEqual } from './enhanceJest'
+import { safeGet } from './safeGet'
+
+test('表现正常', () => {
+  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',
+    },
+  }
+
+  jestExpectEqual(
+    safeGet(obj, 'x'),
+    obj.x,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 's', 'length'),
+    obj.s.length,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'y', 'yy'),
+    obj.y.yy,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'y', 'yy', 'yyyy2'),
+    obj.y.yy.yyyy2,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'y', 'yy', 'yyyy2', 'slice'),
+    obj.y.yy.yyyy2.slice,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'z', 'zz'),
+    obj.z.zz,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'z', 'zzz'),
+    obj.z.zzz,
+  )
+
+  jestExpectEqual(
+    safeGet(obj, 'z', 'zzzz'),
+    obj.z.zzzz,
+  )
+
+  jestExpectEqual(
+    safeGet(obj as any, 'z', 'no', 'no1', 'no2'),
+    undefined,
+  )
+})

src/safeGet.ts

@@ -0,0 +1,110 @@
+import { AnyObject } from './enhanceType'
+import { isNil } from './is'
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+>(obj: T, k0: K0): T[K0]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+>(obj: T, k0: K0, k1: K1): T[K0][K1]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+>(obj: T, k0: K0, k1: K1, k2: K2): T[K0][K1][K2]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3): T[K0][K1][K2][K3]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4): T[K0][K1][K2][K3][K4]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+  K5 extends keyof T[K0][K1][K2][K3][K4],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4, k5: K5): T[K0][K1][K2][K3][K4][K5]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+  K5 extends keyof T[K0][K1][K2][K3][K4],
+  K6 extends keyof T[K0][K1][K2][K3][K4][K5],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4, k5: K5, k6: K6): T[K0][K1][K2][K3][K4][K5][K6]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+  K5 extends keyof T[K0][K1][K2][K3][K4],
+  K6 extends keyof T[K0][K1][K2][K3][K4][K5],
+  K7 extends keyof T[K0][K1][K2][K3][K4][K5][K6],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4, k5: K5, k6: K6, k7: K7): T[K0][K1][K2][K3][K4][K5][K6][K7]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+  K5 extends keyof T[K0][K1][K2][K3][K4],
+  K6 extends keyof T[K0][K1][K2][K3][K4][K5],
+  K7 extends keyof T[K0][K1][K2][K3][K4][K5][K6],
+  K8 extends keyof T[K0][K1][K2][K3][K4][K5][K6][K7],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4, k5: K5, k6: K6, k7: K7, k8: K8): T[K0][K1][K2][K3][K4][K5][K6][K7][K8]
+
+export function safeGet<
+  T extends AnyObject,
+  K0 extends keyof T,
+  K1 extends keyof T[K0],
+  K2 extends keyof T[K0][K1],
+  K3 extends keyof T[K0][K1][K2],
+  K4 extends keyof T[K0][K1][K2][K3],
+  K5 extends keyof T[K0][K1][K2][K3][K4],
+  K6 extends keyof T[K0][K1][K2][K3][K4][K5],
+  K7 extends keyof T[K0][K1][K2][K3][K4][K5][K6],
+  K8 extends keyof T[K0][K1][K2][K3][K4][K5][K6][K7],
+  K9 extends keyof T[K0][K1][K2][K3][K4][K5][K6][K7][K8],
+>(obj: T, k0: K0, k1: K1, k2: K2, k3: K3, k4: K4, k5: K5, k6: K6, k7: K7, k8: K8, k9: K9): T[K0][K1][K2][K3][K4][K5][K6][K7][K8][K9]
+
+export function safeGet(obj: AnyObject, ...path: any[]): any {
+  let last: any = obj
+  const end = path.length - 1
+  for (let i = 0; i < end; i++) {
+    last = last[path[i]]
+    if (isNil(last)) {
+      last = undefined
+      break
+    }
+  }
+  return isNil(last) ? last : last[path[end]]
+}