node:perf_hooks: validate PerformanceObserver.observe options

[andrewtdiz]

Summary

Node PerformanceObserver.prototype.observe() validates its options object: either options.entryTypes or options.type must be specified, entryTypes must be an array when present, and entryTypes cannot be combined with type. Perry currently accepts missing/non-object options and silently ignores invalid shapes.

Node 25.9.0 behavior

const { PerformanceObserver } = require("node:perf_hooks");
const obs = new PerformanceObserver(() => {});

obs.observe();
// TypeError ERR_MISSING_ARGS

obs.observe(null);
// TypeError ERR_INVALID_ARG_TYPE

obs.observe({});
// TypeError ERR_MISSING_ARGS

obs.observe({ entryTypes: "mark" });
// TypeError ERR_INVALID_ARG_TYPE: options.entryTypes must be string[]

obs.observe({ type: "mark", entryTypes: ["measure"] });
// TypeError ERR_INVALID_ARG_VALUE

obs.observe({ entryTypes: [] });        // ok
obs.observe({ entryTypes: ["bogus"] }); // ok, just observes nothing
obs.observe({ type: "bogus" });         // ok, just observes nothing

Perry source evidence

• crates/perry-runtime/src/perf_hooks.rs::js_perf_observer_observe() starts with empty types and buffered = false; if opts is not an object, it simply leaves those values and marks the observer active.
• The function reads entryTypes and only checks arr_v.is_pointer() before treating it as an ArrayHeader; it does not validate that the value is actually an array.
• The function reads type independently and appends it to types; it does not reject the case where both entryTypes and type are present.
• No missing-argument / missing-options validation is performed before activating the observer.

Expected

PerformanceObserver.observe() should match Node's option validation while preserving the current lenient behavior for unsupported but well-typed entry names (bogus observes nothing).

Duplicate checks

• PerformanceObserver observe options validation
• perf_hooks observer observe entryTypes type invalid
• PR search for PerformanceObserver observe

I found merged observer behavior PRs for buffered delivery and callback args, but no issue for observe-option validation.

[andrewtdiz]

I am taking this in a focused node:perf_hooks timing and validation PR cut with #3012, #3013, #3011, #3008, and #3088. Intended scope: make performance.now() relative to a process-start timeOrigin, support two-argument eventLoopUtilization() diffs, and align the related User Timing / observer validation behavior. Non-goals: timerify() function entries and markResourceTiming() resource entries, which fit a separate observable-entry cut.

[andrewtdiz]

Opened PR #3508 to close this: #3508

Verification on the rebased branch:

• Node 24 parity: ./run_parity_tests.sh --suite node-suite --module perf_hooks passed 78/78.
• cargo check -p perry-runtime -p perry-codegen -p perry-hir -p perry-api-manifest -p perry passed.
• cargo fmt --all -- --check, ./scripts/check_file_size.sh, jq empty test-parity/known_failures.json, and git diff HEAD~1..HEAD --check passed.