perf(plugins): report slow boundary compiles

scripts/check-extension-package-tsc-boundary.mjs

@@ -23,6 +23,7 @@ const prepareBoundaryArtifactsBin = resolve(
 );
 const extensionPackageBoundaryBaseConfig = "../tsconfig.package-boundary.base.json";
 const FAILURE_OUTPUT_TAIL_LINES = 40;
+const SLOW_COMPILE_SUMMARY_LIMIT = 10;
 const COMPILE_INPUT_EXTENSIONS = new Set([".ts", ".tsx", ".mts", ".cts", ".js", ".mjs", ".json"]);
 const ROOTDIR_BOUNDARY_CANARY_IMPORT_PATH =
   "../../src/plugins/contracts/rootdir-boundary-canary.ts";
@@ -123,6 +124,23 @@ export function formatSkippedCompileProgress(params = {}) {
   return `skipped ${skippedCount} fresh plugin compiles\n`;
 }
 
+export function formatSlowCompileSummary(params = {}) {
+  const compileTimings = Array.isArray(params.compileTimings) ? params.compileTimings : [];
+  if (compileTimings.length === 0) {
+    return "";
+  }
+
+  const limit =
+    Number.isInteger(params.limit) && params.limit > 0 ? params.limit : SLOW_COMPILE_SUMMARY_LIMIT;
+  const lines = ["slowest plugin compiles:"];
+  for (const timing of [...compileTimings]
+    .toSorted((left, right) => right.elapsedMs - left.elapsedMs)
+    .slice(0, limit)) {
+    lines.push(`- ${timing.extensionId}: ${timing.elapsedMs}ms`);
+  }
+  return `${lines.join("\n")}\n`;
+}
+
 export function formatStepFailure(label, params = {}) {
   const stdoutSection = summarizeOutputSection("stdout", params.stdout ?? "");
   const stderrSection = summarizeOutputSection("stderr", params.stderr ?? "");
@@ -411,7 +429,7 @@ export function runNodeStepAsync(label, args, timeoutMs, params = {}) {
       clearTimeout(timer);
       settled = true;
       if (code === 0) {
-        resolvePromise({ stdout, stderr });
+        resolvePromise({ stdout, stderr, elapsedMs: Date.now() - startedAt });
         return;
       }
       const error = attachStepFailureMetadata(
@@ -454,13 +472,13 @@ export async function runNodeStepsWithConcurrency(steps, concurrency) {
       }
       const step = steps[index];
       step.onStart?.();
-      await runNodeStepAsync(step.label, step.args, step.timeoutMs, {
+      const result = await runNodeStepAsync(step.label, step.args, step.timeoutMs, {
         abortController,
         onFailure(error) {
           firstFailure ??= error;
         },
       });
-      step.onSuccess?.();
+      step.onSuccess?.(result);
     }
   });
   await Promise.allSettled(workers);
@@ -573,6 +591,7 @@ async function runCompileCheck(extensionIds) {
   process.stdout.write(`compile concurrency ${concurrency}\n`);
   const compileStartedAt = Date.now();
   let skippedCompileCount = 0;
+  const compileTimings = [];
   const steps = extensionIds
     .map((extensionId, index) => {
       const tsBuildInfoPath = resolveBoundaryTsBuildInfoPath(extensionId);
@@ -602,8 +621,12 @@ async function runCompileCheck(extensionIds) {
         onStart() {
           process.stdout.write(`[${index + 1}/${extensionIds.length}] ${extensionId}\n`);
         },
-        onSuccess() {
+        onSuccess(result) {
           writeStampFile(resolveBoundaryTsStampPath(extensionId));
+          compileTimings.push({
+            extensionId,
+            elapsedMs: result.elapsedMs,
+          });
         },
         args: [
           tscBin,
@@ -634,6 +657,7 @@ async function runCompileCheck(extensionIds) {
     compileCount: steps.length,
     skippedCompileCount,
     compileElapsedMs: Date.now() - compileStartedAt,
+    compileTimings,
   };
 }
 
@@ -709,12 +733,13 @@ export async function main(argv = process.argv.slice(2)) {
   let compileCount = 0;
   let skippedCompileCount = 0;
   let compileElapsedMs;
+  let compileTimings = [];
   let canaryElapsedMs;
 
   try {
     cleanupCanaryArtifactsForExtensions(cleanupExtensionIds);
     if (mode === "all" || mode === "compile") {
-      ({ prepElapsedMs, compileCount, skippedCompileCount, compileElapsedMs } =
+      ({ prepElapsedMs, compileCount, skippedCompileCount, compileElapsedMs, compileTimings } =
         await runCompileCheck(optInExtensionIds));
     }
     if (shouldRunCanary) {
@@ -732,6 +757,11 @@ export async function main(argv = process.argv.slice(2)) {
         elapsedMs: Date.now() - startedAt,
       }),
     );
+    process.stdout.write(
+      formatSlowCompileSummary({
+        compileTimings,
+      }),
+    );
   } finally {
     releaseBoundaryLock?.();
     teardownCanaryCleanup?.();

test/scripts/check-extension-package-tsc-boundary.test.ts

@@ -7,6 +7,7 @@ import {
   acquireBoundaryCheckLock,
   cleanupCanaryArtifactsForExtensions,
   formatBoundaryCheckSuccessSummary,
+  formatSlowCompileSummary,
   formatSkippedCompileProgress,
   formatStepFailure,
   installCanaryArtifactCleanup,
@@ -206,6 +207,19 @@ describe("check-extension-package-tsc-boundary", () => {
     ).toBe("skipped 97 fresh plugin compiles\n");
   });
 
+  it("formats the slowest plugin compiles in descending order", () => {
+    expect(
+      formatSlowCompileSummary({
+        compileTimings: [
+          { extensionId: "quick", elapsedMs: 40 },
+          { extensionId: "slow", elapsedMs: 900 },
+          { extensionId: "medium", elapsedMs: 250 },
+        ],
+        limit: 2,
+      }),
+    ).toBe(["slowest plugin compiles:", "- slow: 900ms", "- medium: 250ms", ""].join("\n"));
+  });
+
   it("treats a plugin compile as fresh only when its outputs are newer than plugin and shared sdk inputs", () => {
     const { rootDir, extensionRoot } = createTempExtensionRoot();
     const extensionSourcePath = path.join(extensionRoot, "index.ts");
@@ -331,4 +345,25 @@ describe("check-extension-package-tsc-boundary", () => {
 
     expect(Date.now() - startedAt).toBeLessThan(2_000);
   });
+
+  it("passes successful step timing metadata to onSuccess handlers", async () => {
+    const elapsedTimes: number[] = [];
+
+    await runNodeStepsWithConcurrency(
+      [
+        {
+          label: "demo-step",
+          args: ["--eval", "setTimeout(() => process.exit(0), 10)"],
+          timeoutMs: 5_000,
+          onSuccess(result: { elapsedMs: number }) {
+            elapsedTimes.push(result.elapsedMs);
+          },
+        },
+      ],
+      1,
+    );
+
+    expect(elapsedTimes).toHaveLength(1);
+    expect(elapsedTimes[0]).toBeGreaterThanOrEqual(0);
+  });
 });