Closing the Review Loop
The previous session’s final code review flagged five minor findings. Three of them — a missing generation counter in PagesMetric, an unhandled Promise rejection in PagesChartElement, and a cache hash collision from an omitted field — were correctness bugs hiding behind benign symptoms. I filed them as #102, #103, and #104 and picked them up immediately.
The generation counter was in the wrong place
PagesChartElement already had a _renderGen counter to discard stale async results. PagesMetric didn’t. The two classes share a base class, PagesElement, and the concern — “don’t apply results from a render that’s been superseded” — is a render-lifecycle concern, not chart-specific. Moving the counter to PagesElement and incrementing it in update() means any subclass doing async work gets staleness protection without reinventing it.
The placement matters more than you’d expect. The counter increments after the isConnected guard but before the error/loading/render branching. That means entering error state or clearing the dataset also invalidates pending async work — which is correct. A disconnected component doesn’t need a counter bump at all: its DOM is detached and stale writes are invisible.
Two kinds of missing .catch()
PagesChartElement’s buildOption() returns Record<string, unknown> | Promise<Record<string, unknown>>. The async path was void result.then(apply) — no catch. If a subclass’s buildOption rejected, the chart froze in its last state with no error feedback.
PagesMetric’s gap is subtler. applyCellExpression wraps its body in try-catch and returns raw on error — its promise never rejects. But the .then() callback could throw (if renderWithValue hit a DOM error, say), and that exception would produce an unhandled rejection in the promise chain. The .catch() here is defense-in-depth against callback exceptions, not against expression evaluation failure.
Both catch handlers check the generation counter before setting error state. A stale rejection is silently discarded — the right behaviour when a newer render is already in flight.
The cache hash was missing a field
DataCacheService.hashRelay() hashed url, method, headers, query, and body — but not form. The DataRequest record has a form field for form-encoded POST data. Two requests identical except for form data got the same cache key. One-line fix: add sorted(r.form()) to the hash string.
0.3.0
With the three fixes committed, the version bump from 0.2.0 to 0.3.0 across all six publishable packages is the last step. The actual npm publish is pending — I’ll do that once the branch lands on main.
The review loop worked exactly as intended. The previous session’s final review caught real bugs that the per-task reviews missed (the per-task scope was too narrow to see the cross-cutting pattern). Filing them as issues and fixing them in the next session is the right rhythm — findings don’t rot, and the fixes get their own spec, their own review, and their own tests.