好的，我有一个Rails应用程序，它已经升级到Rails 6。我所有的React代码都在目录app/react中，这是我的webpacker.yml文件中的source_path。
rails assets:precompile运行良好，但是当我在本地(以及在生产中(运行./bin/webpack时，我会遇到大量类似于以下语法错误的错误：
WARNING in ./app/react/components/manage/assets/AssetTable/AssetTable.test.js
Module build failed (from ./node_modules/babel-loader/lib/index.js):
SyntaxError: /Users/userj/Development/rails/myapplication/app/react/components/manage/assets/AssetTable/AssetTable.test.js: Unexpected token (28:28)
26 | describe("AssetTable", () => {
27 | it("renders correctly", () => {
> 28 | const wrapper = shallow(<AssetTable />)
| ^
29 | expect(wrapper.exists()).toBe(true)
30 | })
31 |
at Parser._raise (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:742:17)
at Parser.raiseWithData (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:735:17)
at Parser.raise (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:729:17)
at Parser.unexpected (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:8757:16)
at Parser.parseExprAtom (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:10052:20)
at Parser.parseExprSubscripts (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9602:23)
at Parser.parseMaybeUnary (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9582:21)
at Parser.parseExprOps (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9452:23)
at Parser.parseMaybeConditional (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9425:23)
at Parser.parseMaybeAssign (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9380:21)
at Parser.parseExprListItem (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:10718:18)
at Parser.parseCallExpressionArguments (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9790:22)
at Parser.parseSubscript (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9696:31)
at Parser.parseSubscripts (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9625:19)
at Parser.parseExprSubscripts (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9608:17)
at Parser.parseMaybeUnary (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9582:21)
at Parser.parseExprOps (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9452:23)
at Parser.parseMaybeConditional (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9425:23)
at Parser.parseMaybeAssign (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9380:21)
at Parser.parseVar (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11740:26)
at Parser.parseVarStatement (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11549:10)
at Parser.parseStatementContent (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11148:21)
at Parser.parseStatement (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11081:17)
at Parser.parseBlockOrModuleBlockBody (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11656:25)
at Parser.parseBlockBody (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11642:10)
at Parser.parseBlock (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:11626:10)
at Parser.parseFunctionBody (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:10634:24)
at Parser.parseArrowExpression (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:10603:10)
at Parser.parseParenAndDistinguishExpression (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:10221:12)
at Parser.parseExprAtom (/Users/userj/Development/rails/myapplication/node_modules/@babel/parser/lib/index.js:9947:21)
@ ./app/react/components sync ^./.*$ ./manage/assets/AssetTable/AssetTable.test.js
@ ./app/react/packs/server_rendering.js
它似乎没有识别JSX，并将其视为语法错误。
这是我的webpacker.yml文件：
# Note: You must restart bin/webpack-dev-server for changes to take effect
default: &default
source_path: app/react
source_entry_path: packs
public_root_path: public
public_output_path: packs
cache_path: tmp/cache/webpacker
check_yarn_integrity: false
webpack_compile_output: false
# Additional paths webpack should lookup modules
# ['app/assets', 'engine/foo/app/assets']
resolved_paths: []
# Reload manifest.json on all requests so we reload latest compiled packs
cache_manifest: false
# Extract and emit a css file
extract_css: false
static_assets_extensions:
- .jpg
- .jpeg
- .png
- .gif
- .tiff
- .ico
- .svg
- .eot
- .otf
- .ttf
- .woff
- .woff2
extensions:
- .jsx
- .mjs
- .js
- .sass
- .scss
- .css
- .module.sass
- .module.scss
- .module.css
- .png
- .svg
- .gif
- .jpeg
- .jpg
development:
<<: *default
compile: true
# Verifies that versions and hashed value of the package contents in the project's package.json
check_yarn_integrity: true
# Reference: https://webpack.js.org/configuration/dev-server/
dev_server:
https: false
host: localhost
port: 3035
public: localhost:3035
hmr: false
# Inline should be set to true if using HMR
inline: true
overlay: true
compress: true
disable_host_check: true
use_local_ip: false
quiet: false
headers:
'Access-Control-Allow-Origin': '*'
watch_options:
ignored: '**/node_modules/**'
test:
<<: *default
compile: true
# Compile test packs to a separate directory
public_output_path: packs-test
production:
<<: *default
# Production depends on precompilation of packs prior to booting for performance.
compile: false
# Extract and emit a css file
extract_css: true
# Cache manifest.json for performance
cache_manifest: true
这是我的babel.config.js文件：
module.exports = function(api) {
var validEnv = ['development', 'test', 'production']
var currentEnv = api.env()
var isDevelopmentEnv = api.env('development')
var isProductionEnv = api.env('production')
var isTestEnv = api.env('test')
if (!validEnv.includes(currentEnv)) {
throw new Error(
'Please specify a valid `NODE_ENV` or ' +
'`BABEL_ENV` environment variables. Valid values are "development", ' +
'"test", and "production". Instead, received: ' +
JSON.stringify(currentEnv) +
'.'
)
}
return {
presets: [
isTestEnv && [
'@babel/preset-env',
{
targets: {
node: 'current'
}
}
],
(isProductionEnv || isDevelopmentEnv) && [
'@babel/preset-env',
{
forceAllTransforms: true,
useBuiltIns: 'entry',
corejs: 3,
modules: false,
exclude: ['transform-typeof-symbol']
}
]
].filter(Boolean),
plugins: [
'babel-plugin-macros',
'@babel/plugin-syntax-dynamic-import',
isTestEnv && 'babel-plugin-dynamic-import-node',
'@babel/plugin-transform-destructuring',
[
'@babel/plugin-proposal-class-properties',
{
loose: true
}
],
[
'@babel/plugin-proposal-object-rest-spread',
{
useBuiltIns: true
}
],
[
'@babel/plugin-transform-runtime',
{
helpers: false,
regenerator: true,
corejs: false
}
],
[
'@babel/plugin-transform-regenerator',
{
async: false
}
]
].filter(Boolean)
}
}
我很困惑，为什么webpacker会被这些JSX表达式绊倒？
好的，我的解决方案是运行bundle exec rails webpacker:install:react
来源：https://github.com/rails/webpacker/issues/749#issuecomment-328074888