Support cs and csdg standard gates

[danielgaskins]

Summary of changes

cs and csdg are valid stdgates.inc gates, but pyqasm currently rejects them during unrolling. This maps them to the existing controlled-phase decomposition at π/2 and −π/2.

The new tests check both gates with a following measurement, compare their resulting unitaries, and reparse the unrolled QASM. The full suite passes with 909 tests passed and 3 skipped. Black, isort, Pylint, mypy, and whitespace checks pass.

Closes #439.

[argus-eye]

Argus review

Auto-review is off for this repo. Tick the box below to run a review on this PR.

• Trigger Argus review

Estimated cost

• Files changed: 4
• Diff lines (±): 51
• Historical avg: ~317.3k tokens · ~$1.35 · across last 12 review(s)

Tip: you can also comment @argus-eye review at any time.

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository: qBraid/pyqasm/.coderabbit.yaml

Review profile: CHILL

Plan: Advanced

Run ID: 3514b594-b84f-433d-80cb-33a9afb7acbb

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!