fix(types): support inferring inject

types/common.d.ts

@@ -5,7 +5,7 @@ export type UnionToIntersection<U> = (
 ) extends (k: infer I) => void
  ? I
  : never
-
+ 
 // Conditional returns can enforce identical types.
 // See here: https://github.com/Microsoft/TypeScript/issues/27024#issuecomment-421529650
 // prettier-ignore

types/options.d.ts

@@ -174,7 +174,9 @@ export interface ComponentOptions<
  Props = DefaultProps,
  RawBindings = {},
  Mixin extends ComponentOptionsMixin = ComponentOptionsMixin,
- Extends extends ComponentOptionsMixin = ComponentOptionsMixin
+ Extends extends ComponentOptionsMixin = ComponentOptionsMixin,
+ Inject extends InjectOptions = {},
+ InjectNames extends string = string,
 > {
  data?: Data
  props?: PropsDef
@@ -225,7 +227,7 @@ export interface ComponentOptions<
  filters?: { [key: string]: Function }
 
  provide?: object | (() => object)
- inject?: InjectOptions
+ inject?: Inject | InjectNames[]
 
  model?: {
  prop?: string
@@ -342,8 +344,20 @@ export interface DirectiveOptions {
 
 export type InjectKey = string | symbol
 
-export type InjectOptions =
- | {
- [key: string]: InjectKey | { from?: InjectKey; default?: any }
- }
- | string[]
+export type InjectOptions = string[] | ObjectInjectOptions
+
+type ObjectInjectOptions = Record<
+ InjectKey,
+ string | symbol | { from?: string | symbol; default?: unknown }
+>
+
+export type InjectToObject<T extends InjectOptions> =
+ T extends string[]
+ ? {
+ [K in T[number]]?: unknown
+ }
+ : T extends ObjectInjectOptions
+ ? {
+ [K in keyof T]?: unknown
+ }
+ : never

types/test/v3/define-component-test.tsx

@@ -1225,3 +1225,210 @@ describe('should report non-existent properties in instance', () => {
  // @ts-expect-error
  instance2.foo
 })
+
+
+describe('inject', () => {
+ test('with object inject', () => {
+ defineComponent({
+ props: {
+ a: String
+ },
+ inject: {
+ foo: 'foo',
+ bar: 'bar',
+ },
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ // @ts-expect-error
+ expectError(this.foobar = 1)
+ }
+ })
+ })
+
+ test('with array inject', () => {
+ defineComponent({
+ props: ['a', 'b'],
+ inject: ['foo', 'bar'],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ // @ts-expect-error
+ expectError(this.foobar = 1)
+ }
+ })
+ })
+
+ test('with no props', () => {
+ defineComponent({
+ inject: {
+ foo: {
+ from: 'pfoo',
+ default: 'foo'
+ },
+ bar: {
+ from: 'pbar',
+ default: 'bar'
+ },
+ },
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ // @ts-expect-error
+ expectError(this.foobar = 1)
+ }
+ })
+ })
+
+ test('without inject', () => {
+ defineComponent({
+ props: ['a', 'b'],
+ created() {
+ // @ts-expect-error
+ expectError(this.foo = 1)
+ // @ts-expect-error
+ expectError(this.bar = 1)
+ }
+ })
+ })
+
+ test('define mixins w/ no props', () => {
+ const MixinA = defineComponent({
+ inject: {
+ foo: 'foo'
+ },
+ })
+ const MixinB = defineComponent({
+ inject: ['bar'],
+ })
+ // with no props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ }
+ })
+ // with object props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: {
+ baz: {
+ type: Number,
+ required: true
+ }
+ },
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<number>(this.baz)
+ }
+ })
+ // with array props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: ['baz'],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<any>(this.baz)
+ }
+ })
+ })
+
+ test('define mixins w/ object props', () => {
+ const MixinA = defineComponent({
+ props: {
+ a: String
+ },
+ inject: {
+ foo: 'foo'
+ },
+ })
+ const MixinB = defineComponent({
+ props: {
+ b: String
+ },
+ inject: ['bar'],
+ })
+ // with no props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ }
+ })
+ // with object props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: {
+ baz: {
+ type: Number,
+ required: true
+ }
+ },
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<number>(this.baz)
+ }
+ })
+ // with array props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: ['baz'],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<any>(this.baz)
+ }
+ })
+ })
+
+ test('define mixins w/ array props', () => {
+ const MixinA = defineComponent({
+ props: ['a'],
+ inject: {
+ foo: 'foo'
+ },
+ })
+ const MixinB = defineComponent({
+ props: ['b'],
+ inject: ['bar'],
+ })
+ // with no props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ }
+ })
+ // with object props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: {
+ baz: {
+ type: Number,
+ required: true
+ }
+ },
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<number>(this.baz)
+ }
+ })
+ // with array props
+ defineComponent({
+ mixins: [MixinA, MixinB],
+ props: ['baz'],
+ created() {
+ expectType<unknown>(this.foo)
+ expectType<unknown>(this.bar)
+ expectType<any>(this.baz)
+ }
+ })
+ })
+})