Reserve annotation room for the teardown banner independent of the primary excerpt

annotationBody keeps only its own 5-line window of non-empty lines, distinct
from the excerpt's 20-line budget the primary message was reserved against.
A primary message with 5+ non-empty lines already filled that window,
silently dropping the teardown banner and message from the annotation even
though both still fit in the fuller step-summary excerpt.

Author: cderv

src/tools/github.ts

@@ -646,6 +646,12 @@ export function summaryClusterBlock(cluster: FailureCluster): string {
 //    target or claim any row exists; it can only point at the step log.
 export type SummaryRowOutcome = "detail" | "name-only" | "none";
 
+// Non-empty excerpt lines annotationBody keeps by default. Exported so
+// callers building the excerpt (tests/test.ts) can reserve room within this
+// same budget for content that must survive alongside the excerpt, such as a
+// teardown-failure banner.
+export const kAnnotationExcerptLines = 5;
+
 // Trimmed annotation message: the repro, a blank line, the first `maxLines`
 // non-empty excerpt lines (byte-capped defensively, in case a caller passes
 // an excerpt it did not already bound), an ellipsis, then a pointer whose
@@ -655,7 +661,7 @@ export function annotationBody(
   excerpt: string,
   label: string,
   outcome: SummaryRowOutcome,
-  maxLines = 5,
+  maxLines = kAnnotationExcerptLines,
 ): string {
   const allLines = stripAnsi(truncateUtf8Bytes(excerpt, kExcerptMaxBytes))
     .split("\n")

tests/test.ts

@@ -34,6 +34,7 @@ import {
   error as ghError,
   harnessOwnsStep,
   isGitHubActions,
+  kAnnotationExcerptLines,
   kExcerptMaxBytes,
   stripAnsi,
   summaryClusterBlock,
@@ -63,6 +64,11 @@ const kExcerptLines = 20;
 // failure will also be reported: the blank separator, the banner, and at
 // least the first line of the secondary message (see reportFailure).
 const kFinallyReservedLines = 3;
+// Same reservation, but sized for annotationBody's much smaller
+// kAnnotationExcerptLines window rather than kExcerptLines: the banner and
+// the first line of the secondary message, with no separator line (the
+// annotation excerpt is built fresh, not sliced from the primary excerpt).
+const kFinallyAnnotationReservedLines = 2;
 const annotationBudget = new AnnotationBudget();
 // Per-file header flag: each failing test file starts its own summary table.
 let summaryHeaderEmitted = false;
@@ -508,6 +514,26 @@ function reportFailure(
       kExcerptMaxBytes,
     );
 
+    // annotationBody keeps only its first kAnnotationExcerptLines NON-EMPTY
+    // lines of whatever excerpt it's given - a much smaller window than the
+    // kExcerptLines the primary message above was reserved against. A
+    // primary message with as few as kAnnotationExcerptLines non-empty lines
+    // already fills that window, silently dropping the teardown banner and
+    // message from the annotation even though both still fit in the fuller
+    // step-summary excerpt. Build the annotation body from a dedicated,
+    // reserved excerpt instead of reusing `excerpt` when a teardown/cleanup
+    // failure rides along; otherwise reuse `excerpt` unchanged.
+    const annotationExcerpt = finallyFailure
+      ? [
+        ...stripAnsi(primary?.message ?? "")
+          .split("\n")
+          .filter((line) => line.trim().length > 0)
+          .slice(0, kAnnotationExcerptLines - kFinallyAnnotationReservedLines),
+        bannerFor(finallyFailure.phase),
+        describeThrow(finallyFailure.value).message,
+      ].join("\n")
+      : excerpt;
+
     // Record the failure step-wide (sidecar counter) to get its
     // ordinal, then build the navigation label. This runs for EVERY
     // CI failure — including orchestrated bucket legs, whose rows
@@ -587,7 +613,7 @@ function reportFailure(
     // cross-reference their summary entry.
     if (harnessOwnsStep()) {
       if (decision.emitAnnotation) {
-        ghError(annotationBody(repro, excerpt, label, rowOutcome), {
+        ghError(annotationBody(repro, annotationExcerpt, label, rowOutcome), {
           file: annotationFile,
           title: `${label} · ${ctx.testName}`,
         });

tests/unit/harness-failure-reporting.test.ts

@@ -310,6 +310,21 @@ unitTest("harness-reporting - a many-line primary message still leaves room for
     run.summary.includes("FIXTURE_MULTILINE_TEARDOWN_BOOM"),
     "the teardown failure message must survive too",
   );
+  const annotations = annotationsFor(
+    run.stdout,
+    "fixture throws a multi-line message and teardown also throws",
+  );
+  assertEquals(annotations.length, 1);
+  assert(
+    annotations[0].includes("TEARDOWN ALSO FAILED:"),
+    `the annotation's own 5-line window must also survive the many-line primary; annotation was:\n${
+      annotations[0]
+    }`,
+  );
+  assert(
+    annotations[0].includes("FIXTURE_MULTILINE_TEARDOWN_BOOM"),
+    "the annotation must also name the teardown failure, not just the summary",
+  );
 });
 
 unitTest("harness-reporting - a primary message that trips both the line and byte caps still leaves room for the teardown banner and message", async () => {
@@ -329,6 +344,23 @@ unitTest("harness-reporting - a primary message that trips both the line and byt
     run.summary.includes("FIXTURE_BOTHCAPS_TEARDOWN_BOOM"),
     "the teardown failure message must survive too",
   );
+  // escapeProperty encodes "," to "%2C" in the annotation title, so match on
+  // a comma-free slice of the fixture name rather than the literal string.
+  const annotations = annotationsFor(
+    run.stdout,
+    "with teardown throwing too",
+  );
+  assertEquals(annotations.length, 1);
+  assert(
+    annotations[0].includes("TEARDOWN ALSO FAILED:"),
+    `the annotation's own 5-line window must also survive both caps; annotation was:\n${
+      annotations[0]
+    }`,
+  );
+  assert(
+    annotations[0].includes("FIXTURE_BOTHCAPS_TEARDOWN_BOOM"),
+    "the annotation must also name the teardown failure, not just the summary",
+  );
 });
 
 unitTest("harness-reporting - a passing test produces no row and no annotation", async () => {