Yes, the output is uglier. But, this is necessary for me to refactor
`replaceSupers` for #7733, which is necessary for both #7555 and
https://github.com/babel/babel/pull/7553#issuecomment-381434519.
I'm still in the middle of cleaning up all this code. Don't expect
`transformClass` to survive much longer as it's written currently.
We were using `Object.create` to setup the prototype chain at the start of the class definition, which lead to #7771.
I was a bit worried about a speed hit, but it seems everyone optimizes the two patterns the same way.
https://jsbench.github.io/#f9fca52407643d96458a35763b201215Fixes#7771.
* Implement MemberExpressionToFunctions helper
Fixes#7733.
This will also be used to simplify the Private Fields transform, which had [almost the same code](ccd941057a/packages/babel-plugin-proposal-class-properties/src/index.js (L114-L217)) hand written.
* Cleanup
* Little more comment cleanup
* Use unary plus
This can't be redefined, unlike the `Number` identifier.
* Review comments
* Remove unused deps
* Fix class properties after nested class' bare super
Fixes#7371.
* Fix node 4 test
* This damn node 4 test
* All of the ClassBody, but not the methods or field inits
* tmp
* tmp
* Use common class environment visitor
* Tests
* Use skipKey to avoid recursive traversal
* Remove old state
* Use jest expect
* Properly traverse nested class for supers
* Add object nested in class cases
* Add object nested object cases
* Test class properties
* Undo changes to lerna.json
* Add tests arournd prefix/postfix super increment
* tmp
* Use sets
* Improve get/set helper
* fixtures
* Edge cases
* Add loose edge cases
* Spec compliant
* Add issue case
* Even more edge cases!
* Final updates
* Fix name
* Use Reflect.{get, set} when available
* Avoid block scoping in loose
* Remove semicolon
* Do not redefine a non-enumerable
* Get strictness from call site, not helpers
* Add called assertions
* Classes are always strict
* Update test fixture
* #7349
- Add "use strict" directive to transformed class bodies
* Update tests (#7349)
* Add test for program with use strict directive (#7349)
* Update tests (#7349)
* Update source mapping (#7349)
* Add test for parent blockStatement with use strict directive (#7349)
* Update tests (#7349)
* Update tests (#7349)
* Update tests (#7349)
* Add test for constructor-only class (#7349)
* Constructor only classes are strict, too
But constructor only that use non-simple parameters must use a strict function wrapper.
* Fix test
* Wrapper not needed if class is already strict
* Revert change to lerna.json
The boolean expressions returns false in environments where Map is missing.
This change explicitly sets _cache to undefined in such cases, to ensure the cache methods will be ignored.