[Refactoring] Split `src/docker-manager.test.ts` into focused test files

[github-actions]

Refactoring Opportunity

Summary

• File: src/docker-manager.test.ts
• Current size: 5,472 lines
• Responsibilities identified: 7+ distinct test suites in one file

Evidence

The test file mirrors the mixed responsibilities of src/docker-manager.ts and is extremely hard to navigate:

Describe block	Approx. lines
subnetsOverlap, validateIdNotInSystemRange, misc utilities	lines 19–319
generateDockerCompose	lines 320–3634 (~3,300 lines)
writeConfigs	lines 3635–3979
startContainers	lines 3980–4179
stopContainers / fastKillAgentContainer	lines 4180–4350
runAgentCommand	lines 4351–4560
cleanup	lines 4561–5472

The generateDockerCompose describe block alone is ~3,300 lines — larger than most source files in the repo. It contains nested describes for env file, host access, API proxy sidecar, DNS-over-HTTPS, CLI proxy, NO_PROXY baseline, and more.

Proposed Split

src/docker-manager.test.ts (5,472 lines) could be split to match the proposed source module splits (see issue #2473):

• src/host-env.test.ts — utility/host-env function tests (~300 lines)
• src/compose-generator.test.ts — generateDockerCompose tests (~3,300 lines → still large but scoped)
• src/container-lifecycle.test.ts — startContainers, runAgentCommand, stopContainers, fastKillAgentContainer tests (~700 lines)
• src/cleanup.test.ts — writeConfigs, cleanup, collectDiagnosticLogs tests (~700 lines)

Even without splitting the source module, the test file should be split to allow Jest --testPathPattern targeting and faster contributor navigation.

Affected Callers

No imports from test files; splitting is purely organizational. Jest configuration in jest.config.js picks up all *.test.ts files automatically.

Effort Estimate

Medium — mechanical split with shared beforeEach/mock setup that needs careful extraction.

Benefits

• Running npx jest compose-generator isolates ~3,300 lines of tests vs. running the full 5,472-line file
• Reduces PR diff noise — changes to lifecycle rarely touch compose generation
• Mirrors source structure for easier navigation

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Detected by Refactoring Scanner workflow. Run date: 2026-05-04

Generated by Refactoring Opportunity Scanner · ● 233.7K · ◷

• expires on Jul 3, 2026, 6:39 AM UTC