fix(ts): raise TSError for class accessors with discarding accessibility

[fedeci]

Q	A
Fixed Issues?	Closes #13125
Patch: Bug Fix?	Yes
Major: Breaking Change?
Minor: New Feature?
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

We override ClassScopeHandler in the TS plugin so that it is possible to check for class accessors with different accessibility levels.
In this PR we do not take into account MemberExpression and CallExpression keys because TS does not return any error for those

[fedeci]

I think this is a TS bug 🤔

[babel-bot]

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/47131/

[codesandbox-ci]

This pull request is automatically built and testable in CodeSandbox.

To see build info of the built libraries, click here or the icon next to each commit SHA.

Latest deployment of this branch, based on commit d97eda5:

Sandbox	Source
babel-repl-custom-plugin	Configuration
babel-plugin-multi-config	Configuration

[fedeci]

Cannot call 'this.stack.push' because 'ClassScope' [1] is incompatible with 'IClassScope' [2] in array element.
Why this? Shouldn't it be allowed since IClassScope: ClassScope?

[JLHwung]

It seems that the behaviour of different accessibility for accessors has changed in TS 4.3:

class Foo {
  public get f() { return 1 }
  private set f(x) {}
}

is now allowed. https://www.typescriptlang.org/play?target=8&ts=4.3.0-dev.20210503#code/MYGwhgzhAEBiD29oG8BQ1oAcCuAjEAlsNAOYCmALtAGYAUAlCtAE6XbMB20AjNAL7oszAgDcwFMtAiUatAB6NkAvkA

Based on that we may want to hold off this PR and close #13125 since it does not throw on TS 4.3

[fedeci]

class Foo {
    protected get foo() { return 1 }
    set foo(v: any) { }
}

In 4.3.0 accessors are allowed to have a different accessibility level, but getters must have at least the same level of the setters. https://www.typescriptlang.org/play?ts=4.3.0-beta#code/MYGwhgzhAEBiD29oG8BQ0PQA4Cd4BcBTYIgE2gHND9oAzRACgEoVodqBXHAO2gEZoAX3SYI1OowBuALmhhuATxbIhqQUA
Ref PR: microsoft/TypeScript#42425

[fedeci]

Closing this, we may want to check the correct behaviour when implementing auto accessors