THRIFT-6040: Switch JS/Node generator and runtime from Q to native Promise

[jimexist]

Summary

Removes the runtime dependency on the q Promise library and switches the JS/TS code generator to emit native Promise by default. Adds a js:native_promise=[true|false] compiler flag (default true) so users who still need the old output can opt back in.

What changed

Compiler (compiler/cpp/src/thrift/generate/t_js_generator.cc)

• In non-ES6 mode the generated processor now emits new Promise((resolve) => resolve(handler.fn(args))) instead of Q.fcall(...).
• The non-ES6 Node client now emits new Promise((resolve, reject) => { ... }) instead of Q.defer() / _defer.promise.
• The non-ES6 JS/TS _includes no longer pull in Q by default.
• New flag js:native_promise=[true|false] (default true). When false, the legacy Q.fcall / Q.defer output is restored and Q is imported directly via require('q') (no longer routed through thrift.Q), so legacy users only need q in their own node_modules.

Runtime (lib/nodejs/lib/thrift/index.js, lib/nodejs/lib/thrift/browser.js)

• Removed exports.Q = require("q").

Dependencies (package.json, package-lock.json, lib/nodejs/test/package-lock.json)

• Dropped q from dependencies and @types/q from devDependencies; pruned the matching lockfile entries.

Tests (lib/nodets/test/test_driver.ts, lib/nodets/test/test_handler.ts)

• Q.IPromise<T> → Promise<T>; Q.resolve(x) → Promise.resolve(x); .fail(...) → .catch(...).
• Removed import Q = require("q") / import Q = thrift.Q.
• AsyncThriftTestHandler method return types changed to Promise<void> since the callback delivers the value and the body returns Promise.resolve() (native Promise<void> is not assignable to Promise<string> etc. under TS strict mode, unlike Q's loose typings).
• Renamed "Q Promise Client Tests" → "Promise Client Tests".

Why

q has been in maintenance mode for years; native Promise is available in every supported runtime (node >= 10.18.0 per package.json). Removing it shrinks the dependency footprint and brings the non-ES6 / Node output in line with what the ES6 generator already emitted. The native_promise flag is an escape hatch for downstream code that still depends on the Q-shaped output.

Heads-up for reviewers

• A JIRA ticket should be filed under THRIFT — this is non-trivial and the PR title / commit should be prefixed with the ticket ID before merge.
• I was unable to run the JS/TS toolchain or build the C++ compiler in my environment. Please verify locally: npm run lint, npm run test-ts, and a thrift compiler build that regenerates an example service in both default and native_promise=false modes.
• The runtime export thrift.Q is gone; downstream code that imported it will break. Users who need to keep it can use the new native_promise=false generator flag and install q themselves.

Test plan

• make style passes
• npm run lint and npm run test-ts pass
• Thrift compiler builds; generated code for a sample .thrift service is valid JS/TS under both native_promise defaults
• native_promise=false output still works against a project that has q installed
• CI green

🤖 Generated with Claude Code

[Copilot]

Pull request overview

This PR removes the Node.js runtime dependency on the q Promise library and updates the JS/TS code generator to emit native Promise-based code by default, with an opt-out js:native_promise=false flag to restore legacy Q-shaped output.

Changes:

• Dropped q (and @types/q) from npm dependencies and removed the thrift.Q runtime export.
• Updated the JS/TS generator to default to native Promise code paths and added a native_promise generator option to toggle legacy Q output/imports.
• Updated Node TS tests to use native Promise APIs (Promise.resolve, .catch) and removed Q typing/usages.

Reviewed changes

Copilot reviewed 6 out of 8 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
compiler/cpp/src/thrift/generate/t_js_generator.cc	Adds native_promise option and switches non-ES6 generated code paths from Q to native Promises by default.
lib/nodejs/lib/thrift/index.js	Removes exports.Q from the Node runtime entrypoint.
lib/nodejs/lib/thrift/browser.js	Removes exports.Q from the browser runtime entrypoint.
package.json	Removes q from dependencies and @types/q from devDependencies.
package-lock.json	Prunes q / @types/q entries from the lockfile.
lib/nodejs/test/package-lock.json	Prunes q / @types/q entries from the test lockfile.
lib/nodets/test/test_handler.ts	Migrates test handlers from Q promises to native Promise return types and helpers.
lib/nodets/test/test_driver.ts	Migrates promise-client tests from .fail/Q patterns to .catch/native Promise patterns.

Files not reviewed (1)

• lib/nodejs/test/package-lock.json: Language not supported

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.