Currently, 3 options are implemented:
- options.prune (defaults to `false`) - Remove null or undefined
fields from the object after merging.
- options.merge (defaults to `true`) deep-merge nested fields, note
that dependency fields are always deep merged regardless of this option.
- options.warnIncompatibleVersions (defaults to `true`) Output warning
if two dependency version ranges don't intersect.
Closes#4779
* refactor: extract deps & config logic to separate files
* feat: implement a migrator to upgrade to eslint 6
* fix: add required deps for eslint v4
* test: move migrator tests to each standalone plugins
* refactor: use spread operator instead of Object.assign
* refactor: use babel overrides to transpile babel runtime helpers
As recommended in babel/babel#9903.
Get rid of the module-resolver plugin, may fix#3928.
Seems to have fixed#4742 as well.
There may be a small breaking change: as we now use `excludes` & `includes`, babel requires `filename` option to be present (introduced in https://github.com/babel/babel/pull/10181/files). So users who call `babel.transformSync` directly may encounter an error.
However, as we explicitly stated that this preset is only used for Vue CLI internally, I don't expect too many such use cases there. And the error messages are clear enough.
Considering the benefits that this PR brings, I think it's an acceptable tradeoff.
test: update tests for babel
* test: fix windows tests
* test: remove unused variables
* fix: fix scope package paths on Windows
* test: wait some time in router tests in case dom hasn't updated in time
* Enforces require.resolve for loaders
* Updates the lockfile
* Fixes more things
* Adds an extra check
* test(loaders): fix the tests
* style(cli): fix the linting
* style(cli): fix the linting (on windows)
* Update package.json
* Updates the lockfile
* chore: sync dependency versions
* chore: sync dependency versions
* chore: don't introduce unnecessary changes in yarn.lock
* extraneous space
The recast print utility prefers double quotes by default,
this may fail many users' eslint check, so we have to implement a
detection utility to tell if double quotes are actually needed.
Template literals are also converted to string literals, to make things
easier for future iterations.
