fix(scope): allow the co-located test sibling of an in-scope source

[agjs]

Found by a discovery eval sweep (running evals to surface real friction, per the established loop). A 4-seed edit-heavy sweep against the local cluster blocked 2 of 4 (query, checkout) — both dead-stalled to the cycle cap on test-sibling-required.

Root cause: an unsatisfiable harness contradiction

• The gate's test-sibling-required demands the model add a co-located test (e.g. lexer.test.ts) for any logic file it changed.
• But the task's editable scope lists only the sources (files: lexer.ts, parser.ts, executor.ts, query.ts), and writable() does literal/glob matching — so writable("lexer.test.ts", scope) returned false.
• → The rule requires a file the scope forbids. Unsatisfiable → the model thrashes to the cycle cap. Any model stalls here.

Confirmed directly:

writable("lexer.test.ts", ["lexer.ts","parser.ts","executor.ts","query.ts"]) === false

checkout hit the identical wall on pricing.test.ts. Single-file seeds (slugify) escaped it because their one acceptance test is provided, satisfying the sibling.

Fix

writable() now also allows a *.test.* / *.spec.* sibling whose underlying source is in scope (co-located): lexer.test.ts is writable iff lexer.ts is.

• isInScope stays literal (unchanged) — the allowance lives only in writable().
• Can't write a test for an out-of-scope source (pricing.test.ts, evil.test.ts still rejected).
• Traversal/absolute paths still rejected first.

Tests

• scope: co-located siblings of in-scope sources are writable; out-of-scope-source tests are not; the source itself stays writable; isInScope stays literal.
• bun run validate green (1832 tests).

Note

The model also thrashed sub-optimally (kept editing lexer.ts instead of creating the test), but the scope contradiction is the root enabling condition — with it fixed, the gate's instruction ("Add lexer.test.ts") is now actually followable. Mirrored tests/ paths (the rule's secondary option) are a possible follow-up; co-located is what the rule suggests first and what unblocks the observed stalls.

[gemini-code-assist]

Code Review

This pull request updates the writable function to implicitly allow writing to co-located test files (e.g., *.test.* or *.spec.*) of in-scope source files, preventing potential deadlocks. The review feedback highlights a gap where a .tsx or .jsx source file is in scope but its test file uses a .ts or .js extension, and suggests handling this case along with adding a corresponding test.

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[Copilot]

Pull request overview

This PR resolves a harness contradiction where test-sibling-required can demand creation of a co-located test file that the editable scope previously forbade, causing unsatisfiable tasks and model stalls. It updates the scope write-check to implicitly allow *.test.* / *.spec.* siblings when (and only when) the underlying source stem is in scope, and adds regression tests for the behavior.

Changes:

• Extend writable() to allow co-located *.test.* / *.spec.* siblings when a corresponding in-scope source file exists.
• Add a regression test covering co-located test sibling allowance and ensuring isInScope stays literal.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
packages/core/src/lib/scope/scope.ts	Implements the “test sibling of in-scope source is writable” allowance in writable() via a testStem() + source-extension check.
packages/core/tests/scope.test.ts	Adds regression coverage proving co-located test siblings become writable while isInScope remains unchanged.

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