Fix missing TS2385 error for constructor overload visibility disagreement

[Copilot]

tsgo was not reporting TS2385 when constructor overload signatures had mismatched visibility modifiers (public/private/protected), while TypeScript correctly errors:

class Foo {
    private constructor(init: string)  // Should error
    constructor(init: number)
    constructor(init: number | string) { }
}

Changes

• internal/checker/checker.go: Added core.OrElse fallback in checkFlagAgreementBetweenOverloads when reporting visibility disagreement errors. GetNameOfDeclaration returns nil for constructors (they have no name field), causing diagnostics to be created with no location and silently ignored. Now falls back to the overload node itself, matching TypeScript's getNameOfDeclaration(o) || o pattern.

• Test coverage: The fix corrects the existing submodule test classConstructorOverloadsAccessibility.ts from the TypeScript test suite, which now properly reports 3 errors instead of 0.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Missing error for overload signature visibility disagreement</issue_title>
<issue_description>## Steps to reproduce

class Foo {
    private constructor(init: string)
    constructor(init: number)
    constructor(init: number | string) {
        
    }
}

Behavior with typescript@6.0

test.ts:2:5 - error TS2385: Overload signatures must all be public, private or protected.

2     private constructor(init: string)
      ~~~~~~~~~~~~~~~~~~~

Behavior with tsgo

No errors</issue_description>

<agent_instructions>Check _submodules/TypeScript to verify where the error is supposed to be issued</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes Missing error for overload signature visibility disagreement #2705

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[andrewbranch]

@copilot delete the new test and baselines because it looks like an existing submodule test was fixed.

[Copilot]

@copilot delete the new test and baselines because it looks like an existing submodule test was fixed.

Done. Deleted the new test case and baselines. The fix now only includes the code change and the corrected submodule baseline. (4f1f721)

[jakebailey]

Old code was

error(getNameOfDeclaration(o) || o, Diagnostics.Overload_signatures_must_all_be_public_private_or_protected);

sneaky

[Copilot]

Pull request overview

Fixes a TypeScript conformance gap where tsgo failed to emit TS2385 for constructor overloads with mismatched visibility by ensuring diagnostics attach to a valid node for constructors.

Changes:

• Fix diagnostic location for TS2385 visibility mismatch by falling back from missing constructor name nodes to the overload node.
• Update the conformance baseline to reflect the now-reported TS2385 errors.
• Remove the no-longer-needed baseline .diff artifact.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
internal/checker/checker.go	Ensures TS2385 is reported for constructor overload visibility mismatches by using a valid fallback node for errors.
testdata/baselines/reference/submodule/conformance/classConstructorOverloadsAccessibility.errors.txt	Updates expected error output to include the newly surfaced TS2385 diagnostics and spans.
testdata/baselines/reference/submodule/conformance/classConstructorOverloadsAccessibility.errors.txt.diff	Removes an outdated/now-unnecessary diff artifact after updating the baseline.

Comments suppressed due to low confidence (1)

internal/checker/checker.go:1

• Only the TS2385 (visibility) branch uses a fallback node when GetNameOfDeclaration(overload) is nil (constructors). The other diagnostic branches still pass GetNameOfDeclaration(overload) directly, which can reintroduce the same ‘missing diagnostic location’ issue for constructors if those deviation cases ever apply. Consider computing a single errorNode := core.OrElse(ast.GetNameOfDeclaration(overload), overload) once and using it for all c.error(...) calls in this switch.