[Test] Disable Warp autodiff in test suite

[StafaH]

Summary

• Disable Warp backward code generation before pytest collection to reduce cold kernel compile times.
• Keep lightweight tooling compatible when Warp is not installed.
• Run the test matrix when the root pytest configuration changes; the cache warmer uses the same configuration.

Validation

• Warp-free tools tests: 29 passed
• uv run isaaclab -f

[isaaclab-review-bot]

Isaac Lab Review Bot

The change disables Warp backward-code generation from the repo-root pytest configuration before test-module collection and extends the existing ordering regression test to cover that shared setting. The proposed changelog finding does not apply because the trusted repository rule requires package fragments for user-visible changes, while this is test-only infrastructure.

• Design and architecture: The session-wide Warp setting is placed in the shared repo-root conftest, ensuring it is applied before test modules are collected and allowing test-runner consumers such as cache warming to inherit the behavior.
• API: No public Isaac Lab APIs, CLI arguments, configuration fields, exports, or return types are changed. The compatibility surface is limited to pytest execution and Warp kernel generation during tests.
• Implementation: The assignment occurs immediately after importing Warp and before pytest loads test modules. The added regression test resolves the repository root correctly and verifies that the shared conftest contains the expected setting. Its literal-string check is intentionally narrow and may require maintenance if the equivalent assignment is reformatted, but this is not a merge-blocking issue.

No blocking issues. No inline issue met the actionable-evidence threshold; the assessment above records the review feedback.

Automated review; human maintainers own approval decisions.

[greptile-apps]

Greptile Summary

This PR disables Warp backward-code generation in the repository-wide pytest configuration before test collection and extends the existing ordering regression coverage.

• Imports Warp and sets enable_backward to false in the root conftest.
• Adds a test asserting that the shared pytest configuration contains the setting.

Confidence Score: 4/5

The PR appears safe to merge, with one non-blocking weakness in the new regression test’s ability to detect ordering or executability regressions.

The runtime configuration is currently placed before imports that can create Warp modules, and existing tests do not rely on Warp autodiff; only the new guard’s future regression coverage is incomplete.

Files Needing Attention: source/isaaclab/test/test_scripts_warp_backward_ordering.py

Important Files Changed

Filename	Overview
conftest.py	Disables Warp backward generation before plugin registration and test collection; no current incompatible Warp-autodiff test usage was found.
source/isaaclab/test/test_scripts_warp_backward_ordering.py	Adds coverage for the root conftest, but its substring-only assertion does not protect the required execution ordering.

_{Reviews (1): Last reviewed commit: "[Test] Disable Warp autodiff in tests" | Re-trigger Greptile}

[greptile-apps]

Substring check misses ordering regressions

This assertion passes when the assignment appears after an import that creates Warp modules or survives only in a comment or string, so the cold-compilation regression can return without this ordering test detecting it. Match an executable assignment and verify its position, as the entry-script checks above do.