Cannot import Vue file without .vue extension (typescript)

[amcsi]

Version

4.4.1

Reproduction link

https://github.com/amcsi/vue-cli-ts-problem-demo

Environment info

Environment Info:

  System:
    OS: Linux 5.4 Ubuntu 20.04 LTS (Focal Fossa)
    CPU: (12) x64 Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
  Binaries:
    Node: 10.17.0 - ~/.nvm/versions/node/v10.17.0/bin/node
    Yarn: 1.22.4 - ~/.nvm/versions/node/v10.17.0/bin/yarn
    npm: 6.11.3 - ~/.nvm/versions/node/v10.17.0/bin/npm
  Browsers:
    Chrome: 83.0.4103.61
    Firefox: 76.0.1
  npmPackages:
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0 
    @vue/babel-plugin-transform-vue-jsx:  1.1.2 
    @vue/babel-preset-app:  4.4.1 
    @vue/babel-preset-jsx:  1.1.2 
    @vue/babel-sugar-functional-vue:  1.1.2 
    @vue/babel-sugar-inject-h:  1.1.2 
    @vue/babel-sugar-v-model:  1.1.2 
    @vue/babel-sugar-v-on:  1.1.2 
    @vue/cli-overlay:  4.4.1 
    @vue/cli-plugin-babel: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-e2e-cypress: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-eslint: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-router: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-typescript: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-unit-jest: ~4.4.0 => 4.4.1 
    @vue/cli-plugin-vuex: ~4.4.0 => 4.4.1 
    @vue/cli-service: ~4.4.0 => 4.4.1 
    @vue/cli-shared-utils:  4.4.1 
    @vue/component-compiler-utils:  3.1.2 
    @vue/eslint-config-prettier: ^6.0.0 => 6.0.0 
    @vue/eslint-config-typescript: ^5.0.2 => 5.0.2 
    @vue/preload-webpack-plugin:  1.1.1 
    @vue/test-utils: ^1.0.3 => 1.0.3 
    @vue/web-component-wrapper:  1.2.0 
    eslint-plugin-vue: ^6.2.2 => 6.2.2 
    jest-serializer-vue:  2.0.2 
    typescript: ~3.9.3 => 3.9.3 
    vue: ^2.6.11 => 2.6.11 
    vue-eslint-parser:  7.1.0 
    vue-hot-reload-api:  2.3.4 
    vue-jest:  3.0.5 
    vue-loader:  15.9.2 
    vue-router: ^3.2.0 => 3.3.2 
    vue-style-loader:  4.1.2 
    vue-template-compiler: ^2.6.11 => 2.6.11 
    vue-template-es2015-compiler:  1.9.1 
    vuex: ^3.4.0 => 3.4.0 
  npmGlobalPackages:
    @vue/cli: 4.4.1

Steps to reproduce

Clone the repo.
Run yarn install.
Run yarn run serve.

What is expected?

It compiles fine without errors.

What is actually happening?

See that there's a TS error: Cannot find module '../views/Home' or its corresponding type declarations.

---

All I did was remove the .vue extension in the index.tsx's import statement that was there out of the box from vue-cli

import Home from "../views/Home.vue";
to
import Home from "../views/Home";

Screenshot:

Possible related issue:
vuejs/vue#5298 (comment)

[haoqunjiang]

It is expected behavior and the linked issue has explained it well.

In the next major version, we'll stop supporting extension-less import of single file components at all (currently there's only the type checking error).

[douglasg14b]

@sodatea Is this documented somewhere for reference?

[nVitius]

It is expected behavior and the linked issue has explained it well.

In the next major version, we'll stop supporting extension-less import of single file components at all (currently there's only the type checking error).

@sodatea Can you confirm that this change is still expected to occur?