[MattieTK]

Fixes #392

What

assembleBuildResult() (packages/cli/src/lib/deploy-input.ts) prefixed every non-entrypoint Build Output module with ./ when turning the manifest into upload modules. This change uses the manifest path as-is, which is what Wrangler uploads.

Why

Python Workers use module names as file paths without normalising them, and import vendored packages from python_modules/. JavaScript module names are normalised, which is why the prefix went unnoticed. With the prefix, pywrangler sync's vendored workers SDK was uploaded as ./python_modules/workers/__init__.py, so cf deploy of any Python Worker that imports the SDK failed validation:

ModuleNotFoundError: No module named 'workers'
You need to update to workers-py >= 1.9 or to pass disable_python_external_sdk [code: 10021]

I captured both tools' uploads against a fake API: the multipart parts are identical in content and content type, and the part names are the only difference (python_modules/... from Wrangler, ./python_modules/... from cf). Full write-up in #392.

The prefix was also inconsistent within cf itself: the main module was already uploaded unprefixed (index.js), while siblings were ./lib.cjs, ./app.py and so on.

Testing

• Updated the existing assertions in deploy-input.test.ts and commands/deploy/index.test.ts that expected ./-prefixed names.
• Added keeps Python vendored module paths exactly as in the manifest to deploy-input.test.ts.
• deploy-input, deploy/index, previews-deploy and workers-check tests pass. workers check runs Workers that import "./message.js" / require("./helper.cjs"), so relative imports still resolve with unprefixed module names.
• Full run on Linux (WSL2 Ubuntu 22.04, Node 24.22.1):
  • CLI tests: 1948 passed, 1 failed. The failure is cf dev > happy path > reports missing project commands and restores signal listeners, which fails the same way on main (8e51747) in that environment.
  • check:lint, check:format and check:type pass.
• End to end, against a real account, with the same one-line change applied to the published 1.0.0-beta.20 bundle:
  • Python hello world (vendored workers SDK): failed with 10021 before; now deploys and returns 200 Hello from a Python Worker.
  • Rust hello world (worker-build, Wasm + JS shim): still deploys and returns 200 Hello from a Rust Worker.

Includes a patch changeset.

🤖 Generated with Claude Code

[pkg-pr-new]

npm i https://pkg.pr.new/cf@393

commit: 461c643

[clanky-the-clanker]

✅ Approved — This is a small, targeted fix that brings non-entrypoint module names in line with the main module and with Wrangler. It comes with a regression test, updated assertions and a patch changeset, and no issues were found.

_{The decision is advisory: this comment never approves, blocks or requests changes on the pull request.}

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✅ All checks passed

📋 Code Quality: ✅ LGTM

packages/cli/src/lib/deploy-input.ts:277-285 now uses the manifest module name as-is.

• Consistent naming: the main module and sourcemaps are already uploaded unprefixed in the same function, so all module names now follow one rule.
• Path-escape check unchanged: validateModulePath and the filePath resolution still run on the raw manifest name.
• Nothing else depends on the prefix: no other code in the file builds or matches ./-prefixed names.
• Comment: the new inline comment says why the name must be left alone (exact python_modules/ matching), which is what a comment here should do.

Tests cover the change. The existing assertions in deploy-input.test.ts and commands/deploy/index.test.ts now expect unprefixed names. The new keeps Python vendored module paths exactly as in the manifest test would fail if the ./ prefix came back.

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📝 Documentation: ✅ LGTM

The patch changeset .changeset/python-vendored-module-names.md follows the repository's format: "cf": patch frontmatter, an imperative title and a short body.

The body explains the user-visible symptom (No module named 'workers', code 10021) and the fix (matching Wrangler's module naming). A fix change takes a patch bump, which is the bump used here.

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_{Reviewed commit: 3332567d}