fix(wrangler): derive nodejsCompatMode from the effective compatibility inputs in unstable_startWorker

[martijnwalraven]

Makes unstable_startWorker() honor a worker's nodejs_compat compatibility flag, the way wrangler dev does.

The gap. The CLI derives the node-compat mode from the effective compatibility values — input overrides first, then the config file (validateNodeCompatMode(args.compatibilityDate ?? parsedConfig.compatibility_date, args.compatibilityFlags ?? parsedConfig.compatibility_flags ?? [], { noBundle: args.noBundle ?? parsedConfig.no_bundle }) in start-dev.ts). The programmatic path used input.build.nodejsCompatMode raw, so leaving it unset silently ignored the worker's nodejs_compat flag — whether it came from the worker's config file or from input-level compatibilityFlags — and bundling failed to resolve node:* builtins that wrangler dev on the same configuration handles.

The change. When the caller provides no build.nodejsCompatMode, resolveConfig derives it from the same effective values the rest of the resolution uses: input.compatibilityDate ?? config.compatibility_date, input.compatibilityFlags ?? config.compatibility_flags ?? [], and no-bundle from the resolved bundle semantics (!(input.build?.bundle ?? !config.no_bundle) — the programmatic spelling of the CLI's --no-bundle). An explicit value — including null to disable — is still unwrapped exactly as before, so callers owning the mode keep it.

Tests: derived "v2" from a config file carrying compatibility_date + nodejs_compat; derived "v2" from input-level compatibilityFlags over a config file without the flag; explicit null preserved.

---

• Tests
  • Tests included (ConfigController: derived from config file / derived from input-level flags / explicit null preserved)
• Public documentation
  • Documentation not necessary because: bug fix aligning the programmatic dev path with the CLI's compatibility handling; no API surface change. A changeset is included.

🤖 Generated with Claude Code

[changeset-bot]

🦋 Changeset detected

Latest commit: c1a3527

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 3 packages

Name	Type
wrangler	Patch
@cloudflare/vite-plugin	Patch
@cloudflare/vitest-pool-workers	Patch

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commit: c1a3527