fix: Repair module loading logic and have cosmiconfig support ESM+TS

__mocks__/cosmiconfig.js

@@ -1,3 +1,3 @@
 module.exports = {
-  cosmiconfigSync: jest.fn(),
+  cosmiconfig: jest.fn(),
 }

index.ts

@@ -1,4 +1,4 @@
 export type { VueTransformation } from '~/types/VueTransformation'
 export type { Config as SfcmodConfig } from '~/config.schema'
 
-export { default as runTransformation } from '~/runTransformation'
+export { runTransformation } from '~/runTransformation'

package.json

@@ -56,6 +56,7 @@
     "@types/jscodeshift": "^0.11.6",
     "@types/yargs": "^17.0.24",
     "cosmiconfig": "^8.3.4",
+    "cosmiconfig-typescript-loader": "^5.0.0",
     "debug": "^4.1.1",
     "fuzzy": "^0.1.3",
     "globby": "^13.2.2",

src/__tests__/bin.spec.ts

@@ -1,14 +1,16 @@
 import fs from 'fs'
+import path from 'path'
 
-import { cosmiconfigSync } from 'cosmiconfig'
+import { cosmiconfig } from 'cosmiconfig'
 import { globbySync } from 'globby'
-import { prompt } from 'inquirer'
+import inquirer from 'inquirer'
 import { vol } from 'memfs'
 
 import { main } from '../bin'
+import { loadModuleFromPath } from '../utils/loadModuleFromPath'
 
 jest.mock('fs')
-jest.mock('fs/promises')
+jest.mock('../utils/loadModuleFromPath')
 
 /* TEST UTILS */
 async function runBinary(...args: string[]) {
@@ -32,12 +34,26 @@ describe('vue-sfcmod binary', () => {
   const search = jest.fn()
 
   beforeEach(() => {
+    loadModuleFromPath.mockImplementation((nameOrPath) => {
+      const customModulePath = path.resolve(process.cwd(), nameOrPath)
+      if (fs.existsSync(customModulePath)) {
+        const content = fs.readFileSync(customModulePath).toString('utf8')
+
+        // eslint-disable-next-line no-eval
+        return eval(content)
+      }
+
+      throw new Error(`Cannot find transformation module ${nameOrPath}`)
+    })
+
     globbySync.mockImplementation((p) => (Array.isArray(p) ? p : [p]))
-    cosmiconfigSync.mockImplementation(() => {
+
+    cosmiconfig.mockImplementation(() => {
       return {
         search,
       }
     })
+
     search.mockImplementation(() => {
       return {
         config: null,
@@ -47,6 +63,7 @@ describe('vue-sfcmod binary', () => {
 
     consoleLogSpy = jest.spyOn(console, 'log').mockImplementation(() => {})
     consoleErrSpy = jest.spyOn(console, 'error').mockImplementation(() => {})
+
     vol.reset()
   })
 
@@ -68,7 +85,11 @@ describe('vue-sfcmod binary', () => {
   })
 
   it('fails when the transformation module path is wrong', async () => {
-    await expect(() => runBinary('Input.vue', '-t', 'foo')).rejects.toThrow(
+    vol.fromJSON({
+      '/tmp/Input.vue': '<template>Hello world</template><script></script>',
+    })
+
+    await expect(() => runBinary('/tmp/Input.vue', '-t', 'foo')).rejects.toThrow(
       'Cannot find transformation module foo',
     )
   })
@@ -90,17 +111,16 @@ describe('vue-sfcmod binary', () => {
         'module.exports = function(file, api, options) { return JSON.stringify(options) }',
     })
 
-    await expect(() =>
-      runBinary(
-        '--foo',
-        'foo',
-        '-t',
-        '/tmp/transformation.cjs',
-        '--bar=bar',
-        '/tmp/Input.ts',
-        '--flag',
-      ),
-    ).not.toThrow()
+    await runBinary(
+      '--foo',
+      'foo',
+      '-t',
+      '/tmp/transformation.cjs',
+      '--bar=bar',
+      '/tmp/Input.ts',
+      '--flag',
+    )
+
     expect(fs.readFileSync('/tmp/Input.ts').toString('utf-8')).toBe(
       '{"foo":"foo","bar":"bar","flag":true}',
     )
@@ -149,16 +169,16 @@ describe('vue-sfcmod binary', () => {
       '/tmp/Input.vue': '<template>Hello world</template><script></script>',
       '/tmp/transformation.cjs': 'module.exports = {}',
     })
-    prompt.mockReturnValueOnce({ preset: '/tmp/transformation.cjs' })
+    inquirer.prompt.mockReturnValueOnce({ preset: '/tmp/transformation.cjs' })
     search.mockImplementation(() => ({
       config: { presets: ['/tmp/transformation.cjs'] },
       filepath: 'mock-sfcmod.config.ts',
       isEmpty: false,
     }))
 
     await expect(() => runBinary('/tmp/Input.vue')).not.toThrow()
-    expect(prompt).toHaveBeenCalled()
-    expect(prompt).toHaveReturnedWith(
+    expect(inquirer.prompt).toHaveBeenCalled()
+    expect(inquirer.prompt).toHaveReturnedWith(
       expect.objectContaining({
         preset: '/tmp/transformation.cjs',
       }),
@@ -178,7 +198,7 @@ describe('vue-sfcmod binary', () => {
       }
     })
 
-    await expect(() => runBinary('Input.vue', '-t', 'foo')).rejects.toThrow(
+    await expect(() => runBinary('/tmp/Input.vue', '-t', 'foo')).rejects.toThrow(
       'Cannot find transformation module foo',
     )
   })
@@ -188,7 +208,7 @@ describe('vue-sfcmod binary', () => {
       '/tmp/Input.vue': '<template>Hello world</template><script></script>',
       '/tmp/transformation.cjs': 'module.exports = {}',
     })
-    prompt.mockReturnValueOnce({ preset: '/tmp/transformation.cjs' })
+    inquirer.prompt.mockReturnValueOnce({ preset: '/tmp/transformation.cjs' })
     const name = jest.fn().mockReturnValue('test')
     search.mockImplementation(() => ({
       config: { presets: [{ glob: '/tmp/transformation.cjs', name }] },
@@ -197,8 +217,8 @@ describe('vue-sfcmod binary', () => {
     }))
 
     await expect(() => runBinary('/tmp/Input.vue')).not.toThrow()
-    expect(prompt).toHaveBeenCalled()
-    expect(prompt).toHaveReturnedWith(
+    expect(inquirer.prompt).toHaveBeenCalled()
+    expect(inquirer.prompt).toHaveReturnedWith(
       expect.objectContaining({
         preset: '/tmp/transformation.cjs',
       }),

src/__tests__/runTransformation.spec.ts

@@ -1,7 +1,7 @@
 /* eslint-env jest */
 import type { Transform } from 'jscodeshift'
 
-import runTransformation from '../runTransformation'
+import { runTransformation } from '../runTransformation'
 import { TemplateTransformation } from '../types/TemplateTransformation'
 
 const unreachableTransform: Transform = () => {

src/bin.ts

@@ -1,7 +1,7 @@
-import * as fs from 'fs'
-import * as path from 'path'
+import fs from 'fs'
 
-import { cosmiconfigSync } from 'cosmiconfig'
+import { cosmiconfig } from 'cosmiconfig'
+import { TypeScriptLoader } from 'cosmiconfig-typescript-loader'
 import createDebug from 'debug'
 import fuzzy from 'fuzzy'
 import { globbySync } from 'globby'
@@ -10,8 +10,9 @@ import inquirerPrompt from 'inquirer-autocomplete-prompt'
 import yargs from 'yargs'
 
 import { isValidConfig } from '~/config.schema'
-import runTransformation from '~/runTransformation'
+import { runTransformation } from '~/runTransformation'
 import type { Options } from '~/types/TransformationOptions'
+import { loadModuleFromPath } from '~/utils/loadModuleFromPath'
 
 /* Find a transform to run and run it on input files. */
 export async function main() {
@@ -20,8 +21,12 @@ export async function main() {
   const debug = createDebug('vue-sfcmod')
 
   /* Load config file. */
-  const explorerSync = cosmiconfigSync('sfcmod')
-  const configResult = explorerSync.search()
+  const explorer = cosmiconfig('sfcmod', {
+    loaders: {
+      '.ts': TypeScriptLoader(),
+    },
+  })
+  const configResult = await explorer.search()
   let config
   if (configResult === null) {
     debug('No config file found.')
@@ -77,22 +82,10 @@ export async function main() {
     }
   }
 
-  /* Load arbitrary transformation module path. */
-  async function loadTransformationModule(nameOrPath: string) {
-    const customModulePath = path.resolve(process.cwd(), nameOrPath)
-    if (fs.existsSync(customModulePath)) {
-      const content = fs.readFileSync(customModulePath).toString('utf8')
-
-      // eslint-disable-next-line no-eval
-      return eval(content)
-    }
-
-    throw new Error(`Cannot find transformation module ${nameOrPath}`)
-  }
-
+  /* Load arbitrary transformation module path or ask the user if not found. */
   let transformationModule
   if (transformationName) {
-    transformationModule = await loadTransformationModule(transformationName)
+    transformationModule = await loadModuleFromPath(transformationName)
   } else {
     const answer = await inquirer.prompt({
       // @ts-expect-error TS does not recognise `type: 'autocomplete'` which would be cumbersome to shim.
@@ -115,7 +108,7 @@ export async function main() {
       },
     })
 
-    transformationModule = await loadTransformationModule(answer.preset)
+    transformationModule = await loadModuleFromPath(answer.preset)
   }
 
   /* Start running. */

src/runTransformation.ts

@@ -14,7 +14,7 @@ import type { Options } from '~/types/TransformationOptions'
 import debug from '~/utils/debug'
 import { normaliseTransformationModule } from '~/utils/normaliseTransformationModule'
 
-export default function runTransformation(
+export function runTransformation(
   fileInfo: FileInfo,
   transformationModule: TransformationModule,
   params: Options = {},

src/utils/loadModuleFromPath.ts

@@ -0,0 +1,20 @@
+import fs from 'fs'
+import path from 'path'
+
+import type { TransformationModule } from '~/types/TransformationModule'
+import debug from '~/utils/debug'
+
+export function loadModuleFromPath(nameOrPath: string): Promise<TransformationModule> {
+  debug(`Loading transformation module ${nameOrPath}`)
+
+  const customModulePath = path.resolve(process.cwd(), nameOrPath)
+  debug(`Resolved to ${customModulePath}`)
+
+  if (fs.existsSync(customModulePath)) {
+    debug('Module exists on filesystem')
+
+    return import(customModulePath)
+  }
+
+  throw new Error(`Cannot find transformation module ${nameOrPath}`)
+}

yarn.lock

@@ -2758,6 +2758,13 @@ cosmiconfig-typescript-loader@^4.0.0:
   resolved "https://registry.yarnpkg.com/cosmiconfig-typescript-loader/-/cosmiconfig-typescript-loader-4.4.0.tgz#f3feae459ea090f131df5474ce4b1222912319f9"
   integrity sha512-BabizFdC3wBHhbI4kJh0VkQP9GkBfoHPydD0COMce1nJ1kJAB3F2TmJ/I7diULBKtmEWSwEbuN/KDtgnmUUVmw==
 
+cosmiconfig-typescript-loader@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/cosmiconfig-typescript-loader/-/cosmiconfig-typescript-loader-5.0.0.tgz#0d3becfe022a871f7275ceb2397d692e06045dc8"
+  integrity sha512-+8cK7jRAReYkMwMiG+bxhcNKiHJDM6bR9FD/nGBXOWdMLuYawjF5cGrtLilJ+LGd3ZjCXnJjR5DkfWPoIVlqJA==
+  dependencies:
+    jiti "^1.19.1"
+
 cosmiconfig@^8.0.0:
   version "8.2.0"
   resolved "https://registry.yarnpkg.com/cosmiconfig/-/cosmiconfig-8.2.0.tgz#f7d17c56a590856cd1e7cee98734dca272b0d8fd"
@@ -4643,6 +4650,11 @@ jest@^29.6.2:
     import-local "^3.0.2"
     jest-cli "^29.6.4"
 
+jiti@^1.19.1:
+  version "1.20.0"
+  resolved "https://registry.yarnpkg.com/jiti/-/jiti-1.20.0.tgz#2d823b5852ee8963585c8dd8b7992ffc1ae83b42"
+  integrity sha512-3TV69ZbrvV6U5DfQimop50jE9Dl6J8O1ja1dvBbMba/sZ3YBEQqJ2VZRoQPVnhlzjNtU1vaXRZVrVjU4qtm8yA==
+
 js-tokens@^4.0.0:
   version "4.0.0"
   resolved "https://registry.yarnpkg.com/js-tokens/-/js-tokens-4.0.0.tgz#19203fb59991df98e3a287050d4647cdeaf32499"