I created a fresh project using vue cli with the following specs:

• vue 3
• typescript
• no class syntax
• vue-router
• babel
• eslint + standard
• jest
• cypress

When I run npm run test:unit I get the below error

TypeScript diagnostics (customize using `[jest-config].globals.ts-jest.diagnostics` option):
    tests/unit/example.spec.ts:7:34 - error TS2769: No overload matches this call.
      The last overload gave the following error.
        Argument of type 'DefineComponent<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 7 more ..., { ...; } | {}>' is not assignable to parameter of type 'ComponentOptionsWithObjectProps<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 6 more ..., { ...; } | {}>'.
          Type 'DefineComponent<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 7 more ..., { ...; } | {}>' is not assignable to type 'ComponentOptionsBase<Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ... 8 more ..., { ...; } | {}>'.
            Types of property 'setup' are incompatible.
              Type '((this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: import("D:/code/personal/js/med...' is not assignable to type '((this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: import("D:/code/personal/js/med...'. Two different types with this name exist, but they are unrelated.
                Type '(this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; slice?: string[] | undefined; ... 16 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: im...' is not assignable to type '(this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; slice?: string[] | undefined; ... 16 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: im...'. Two different types with this name exist, but they are unrelated.
                  Types of parameters 'ctx' and 'ctx' are incompatible.
                    Type 'SetupContext<string[]>' is not assignable to type 'SetupContext<EmitsOptions>'.
                      Type 'EmitsOptions' is not assignable to type 'string[]'.
                        Type 'Record<string, ((...args: any[]) => any) | null>' is missing the following properties from type 'string[]': length, pop, push, concat, and 28 more.

    7     const wrapper = shallowMount(HelloWorld, {
                                       ~~~~~~~~~~

      node_modules/@vue/test-utils/dist/mount.d.ts:36:25
        36 export declare function mount<PropsOptions extends Readonly<ComponentPropsOptions>, RawBindings, D, C extends ComputedOptions = {}, M extends Record<string, Function> = {}, E extends EmitsOptions = Record<string, any>, Mixin extends ComponentOptionsMixin = ComponentOptionsMixin, Extends extends ComponentOptionsMixin = ComponentOptionsMixin, EE extends string = string>(componentOptions: ComponentOptionsWithObjectProps<PropsOptions, RawBindings, D, C, M, E, Mixin, Extends, EE>, options?: MountingOptions<ExtractPropTypes<PropsOptions>, D>): VueWrapper<ComponentPublicInstance<ExtractPropTypes<PropsOptions>, RawBindings, D, C, M, E, VNodeProps & ExtractPropTypes<PropsOptions>>>;
                                   ~~~~~
        The last overload is declared here.

Even though I've used Javascript for a long time I am new to typescript and unable to read the error properly/make sense of it.

The test file code:

import { shallowMount } from '@vue/test-utils'
import HelloWorld from '@/components/HelloWorld.vue'

describe('HelloWorld.vue', () => {
  it('renders props.msg when passed', () => {
    const msg = 'new message'
    const wrapper = shallowMount(HelloWorld, {
      props: { msg }
    })
    expect(wrapper.text()).toMatch(msg)
  })
})

and component code

<script lang="ts">
import { defineComponent } from 'vue'

export default defineComponent({
  name: 'HelloWorld',
  props: {
    msg: String
  }
})
</script>

I created a fresh project using vue cli with the following specs:

• vue 3
• typescript
• no class syntax
• vue-router
• babel
• eslint + standard
• jest
• cypress

When I run npm run test:unit I get the below error

TypeScript diagnostics (customize using `[jest-config].globals.ts-jest.diagnostics` option):
    tests/unit/example.spec.ts:7:34 - error TS2769: No overload matches this call.
      The last overload gave the following error.
        Argument of type 'DefineComponent<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 7 more ..., { ...; } | {}>' is not assignable to parameter of type 'ComponentOptionsWithObjectProps<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 6 more ..., { ...; } | {}>'.
          Type 'DefineComponent<readonly string[] | Readonly<ComponentObjectPropsOptions<Record<string, unknown>>>, unknown, unknown, Record<string, ComputedGetter<any> | WritableComputedOptions<...>>, ... 7 more ..., { ...; } | {}>' is not assignable to type 'ComponentOptionsBase<Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ... 8 more ..., { ...; } | {}>'.
            Types of property 'setup' are incompatible.
              Type '((this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: import("D:/code/personal/js/med...' is not assignable to type '((this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; ... 17 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: import("D:/code/personal/js/med...'. Two different types with this name exist, but they are unrelated.
                Type '(this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; slice?: string[] | undefined; ... 16 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: im...' is not assignable to type '(this: void, props: Readonly<{ [x: number]: string; } & { length?: number | undefined; toString?: string | undefined; toLocaleString?: string | undefined; concat?: string[] | undefined; join?: string | undefined; slice?: string[] | undefined; ... 16 more ...; flat?: unknown[] | undefined; }> | Readonly<...>, ctx: im...'. Two different types with this name exist, but they are unrelated.
                  Types of parameters 'ctx' and 'ctx' are incompatible.
                    Type 'SetupContext<string[]>' is not assignable to type 'SetupContext<EmitsOptions>'.
                      Type 'EmitsOptions' is not assignable to type 'string[]'.
                        Type 'Record<string, ((...args: any[]) => any) | null>' is missing the following properties from type 'string[]': length, pop, push, concat, and 28 more.

    7     const wrapper = shallowMount(HelloWorld, {
                                       ~~~~~~~~~~

      node_modules/@vue/test-utils/dist/mount.d.ts:36:25
        36 export declare function mount<PropsOptions extends Readonly<ComponentPropsOptions>, RawBindings, D, C extends ComputedOptions = {}, M extends Record<string, Function> = {}, E extends EmitsOptions = Record<string, any>, Mixin extends ComponentOptionsMixin = ComponentOptionsMixin, Extends extends ComponentOptionsMixin = ComponentOptionsMixin, EE extends string = string>(componentOptions: ComponentOptionsWithObjectProps<PropsOptions, RawBindings, D, C, M, E, Mixin, Extends, EE>, options?: MountingOptions<ExtractPropTypes<PropsOptions>, D>): VueWrapper<ComponentPublicInstance<ExtractPropTypes<PropsOptions>, RawBindings, D, C, M, E, VNodeProps & ExtractPropTypes<PropsOptions>>>;
                                   ~~~~~
        The last overload is declared here.

Even though I've used Javascript for a long time I am new to typescript and unable to read the error properly/make sense of it.

The test file code:

import { shallowMount } from '@vue/test-utils'
import HelloWorld from '@/components/HelloWorld.vue'

describe('HelloWorld.vue', () => {
  it('renders props.msg when passed', () => {
    const msg = 'new message'
    const wrapper = shallowMount(HelloWorld, {
      props: { msg }
    })
    expect(wrapper.text()).toMatch(msg)
  })
})

and component code

<script lang="ts">
import { defineComponent } from 'vue'

export default defineComponent({
  name: 'HelloWorld',
  props: {
    msg: String
  }
})
</script>

• javascript
• typescript
• unit-testing
• vue.js
• jestjs

4 Answers 4

As suggested at https://github.com/vuejs/vue-test-utils-next/issues/194#issuecomment-695333180

Changing the shim to the below fixes the issue.

declare module '*.vue' {
  import { DefineComponent } from 'vue';
  const component: DefineComponent;
  export default component;
}

As of today, 'propsData' has been deprecated and replaced by 'props'.

Looks like shallowMount requires propsData, not props.

Often times it's not fruitful to bang your head against the wall trying to understand big crazy error messages like those. I usually take a quick look at them, see if there's anything useful, then try some other approaches and only come back to the big error message if those other approaches didn't work out.

The accepted answer worked for me until I needed to add Provide/Inject. NavBar injects userName. The snippet below fails with the same type of error.

    const wrapper = mount(NavBar, {
      props: { msg },
      provide: {
        userName() {
          return "Joe Martin";
        },
      },
    });