default transformFunctions doesn't include jest-resolve's Resolver.resolveModule #375
Comments
|
In the end I wrote a custom jest resolver that reads from my webpack config, uses The implementation could definitely be cleaned up and made a bit more robust/generic, probably some generic 'xConfigAdapter' type things to map jest/babel/etc config -> the appropriate const fs = require('fs')
const path = require('path')
const webpackMerge = require('webpack-merge')
const { CachedInputFileSystem, ResolverFactory } = require('enhanced-resolve')
// TODO: If we wanted to read config out of babel..
// Ref: https://babeljs.io/docs/en/babel-core#advanced-apis
const getSanitisedNodeEnv = () => {
const nodeEnv = process.env.NODE_ENV
switch (nodeEnv) {
case 'development':
case 'test':
case 'production':
return nodeEnv
default:
return 'test'
}
}
const root = fs.realpathSync(process.cwd())
// We want to be able to import from our webpack config
// Refs:
// https://webpack.js.org/configuration/resolve/
// https://webpack.js.org/api/resolvers/
const webpackConfig = require(`${root}/config/webpack/${getSanitisedNodeEnv()}`)
const jestDefaults = require('jest-config').defaults
// We want to be able to import from our jest config
const jestConfig = require(`${root}/jest.config`)
// Ref: https://github.com/facebook/jest/blob/master/packages/jest-runtime/src/cli/index.ts#L59-L68
// TODO: Read the jest config 'properly' (including parsing everything)
// Validation Error: Module jest-localstorage-mock in the setupFiles option was not found.
// console.warn(require('jest-config').readConfig({}, root))
const jestRootDir = jestConfig.rootDir || root
const rootDirReplacer = path => path.replace('<rootDir>', jestRootDir)
const mappedJestDefaults = {
extensions: jestDefaults.moduleFileExtensions.map(ext => `.${ext}`),
}
// Map the relevant jest config options into webpack config layout
// Ref: https://jestjs.io/docs/en/configuration
const mappedJestConfig = {
modules: [
...(jestConfig.roots || []).map(rootDirReplacer),
...(jestConfig.modulePaths || []).map(rootDirReplacer),
...(jestConfig.moduleDirectories || []),
],
extensions: jestConfig.moduleFileExtensions,
}
// TODO: handle https://jestjs.io/docs/en/configuration#modulenamemapper-objectstring-string
// TODO: handle https://jestjs.io/docs/en/configuration#modulepathignorepatterns-arraystring
// Refs:
// https://webpack.js.org/configuration/resolve/#resolvealias
// Note: resolve.alias takes precedence over other module resolutions.
// https://github.com/tleunen/babel-plugin-module-resolver/blob/master/DOCS.md#alias
const jestAliases = {
alias: {
'test-helpers': path.resolve(jestRootDir, 'spec/javascripts/helpers'),
},
}
// Note: When not defined here the strategy defaults to 'append'
const mergeStrategies = {}
// Ref: https://github.com/survivejs/webpack-merge#merging-with-strategies
const mergedResolverFactoryConfig = webpackMerge.smartStrategy(mergeStrategies)(
webpackConfig.resolve,
mappedJestDefaults,
mappedJestConfig,
jestAliases
)
// Refs:
// https://github.com/webpack/enhanced-resolve
// https://github.com/webpack/enhanced-resolve#creating-a-resolver
// https://github.com/webpack/enhanced-resolve#resolver-options
// https://github.com/webpack/enhanced-resolve/wiki/Plugins
// https://github.com/webpack/enhanced-resolve/blob/master/lib/ResolverFactory.js
// https://github.com/webpack/enhanced-resolve/blob/master/lib/node.js#L76-L91
const createSyncResolver = options => {
const resolver = ResolverFactory.createResolver({
useSyncFileSystemCalls: true,
fileSystem: new CachedInputFileSystem(fs, 4000),
...options,
})
// https://github.com/webpack/enhanced-resolve/blob/master/lib/node.js#L13-L15
const context = {
environments: ['node+es3+es5+process+native'],
}
return (baseDir, thingToResolve) =>
resolver.resolveSync(context, baseDir, thingToResolve)
}
const webpackResolver = createSyncResolver(mergedResolverFactoryConfig)
// Ref: https://jestjs.io/docs/en/configuration#resolver-string
const jestWebpackResolver = (path, options) => {
let webpackResolved
let defaultResolved
try {
webpackResolved = webpackResolver(options.basedir, path)
} catch (_error) {
defaultResolved = options.defaultResolver(path, options)
console.warn(
'[JestWebpackResolver] WARNING: Failed to resolve, falling back to default jest resolver:\n',
{ path, options, webpackResolved, defaultResolved }
)
}
return webpackResolved || defaultResolved
}
module.exports = jestWebpackResolver |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
I've configured my alternate search paths as part of this module's
roots(rather than in jest's config), and I get the following:This appears to be because
jest-resolve'sResolver.resolveModuleisn't included in the list of defaulttransformFunctions:Looking at
normalizeTransformedFunctionsI can see that our customtransformFunctionsare appended to the list of defaults:Using a custom jest resolver we can log more info just before this crash happens:
Which shows the following just before it crashes:
This looks as though we should be able to use add
Resolver.resolveModuleto our customtransformFunctions:Though unfortunately this doesn't seem to work.. presumably because
jest-resolveis in ournode_modules, and that isn't getting transpiled by babel, so this plugin never gets a chance to hook it.At this stage I could probably look at hacking something together using a custom
resolvePathfunction:But given the project is looking for maintainers (#346).. it might be better for me to find an alternative solution to my needs.
For those that come across this in future, I was originally wanting centralise my webpack resolving/aliasing in babel, so it could 'just work' among webpack, jest, babel, etc.
Some things that attempt to do similar'ish:
The text was updated successfully, but these errors were encountered: