fix(js): support private methods and static blocks in babel preset - #36218
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The @nx/js/babel preset loads @babel/plugin-transform-class-properties on its own, which runs babel's shared class-features plugin. That plugin hard-errors on #private methods and static blocks unless their companion transforms are loaded too, so babel-jest failed with "Class private methods are not enabled" when transforming an ESM-only dependency that uses such syntax (un-ignored via transformIgnorePatterns). Load the companion class-features transforms next to class-properties: private-methods and private-property-in-object with the same loose setting (babel requires loose to match across the three), plus class-static-block. This clears the whole family of "not enabled" hard-errors, not just private methods.
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…36218) ## Current Behavior The `@nx/js/babel` preset loads `@babel/plugin-transform-class-properties` on its own. That plugin runs babel's shared class-features transform, which hard-errors on `#private` methods and `static {}` blocks unless their companion transforms are also loaded. When babel-jest transforms an ESM-only dependency that uses this syntax (un-ignored through `transformIgnorePatterns`, the documented way to consume ESM-only packages), the transform fails: ``` SyntaxError: Class private methods are not enabled. Please add `@babel/plugin-transform-private-methods` to your configuration. ``` ## Expected Behavior The preset transforms private methods, `#private in obj` checks, and static blocks instead of erroring. It now loads the companion class-features transforms next to `class-properties`: `private-methods` and `private-property-in-object` with the same `loose` setting (babel requires `loose` to match across the three), plus `class-static-block`. This clears the whole family of "not enabled" hard-errors, not just private methods. A regression test covering the affected syntax is added. ## Related Issue(s) Fixes #36205 <!-- polygraph-session-start --> --- [View session information ↗](https://app.trypolygraph.com/orgs/6a061dcb561c062131116eca/sessions/gh-36205-21561609) <!-- polygraph-session-end --> (cherry picked from commit 99d542e)
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Current Behavior
The
@nx/js/babelpreset loads@babel/plugin-transform-class-propertieson its own. That plugin runs babel's shared class-features transform, which hard-errors on#privatemethods andstatic {}blocks unless their companion transforms are also loaded. When babel-jest transforms an ESM-only dependency that uses this syntax (un-ignored throughtransformIgnorePatterns, the documented way to consume ESM-only packages), the transform fails:Expected Behavior
The preset transforms private methods,
#private in objchecks, and static blocks instead of erroring. It now loads the companion class-features transforms next toclass-properties:private-methodsandprivate-property-in-objectwith the sameloosesetting (babel requireslooseto match across the three), plusclass-static-block. This clears the whole family of "not enabled" hard-errors, not just private methods. A regression test covering the affected syntax is added.Related Issue(s)
Fixes #36205
View session information ↗