chore: add typecheck profiling (#35622)

script/profile-typecheck-packages.ts

@@ -0,0 +1,66 @@
+#!/usr/bin/env bun
+
+import path from "path"
+
+const root = path.resolve(import.meta.dir, "..")
+const proc = Bun.spawn(
+  [
+    "bun",
+    "turbo",
+    "typecheck",
+    "--concurrency=1",
+    "--force",
+    "--continue=always",
+    "--summarize",
+    "--output-logs=errors-only",
+  ],
+  {
+    cwd: root,
+    stdout: "pipe",
+    stderr: "pipe",
+  },
+)
+const [stdout, stderr, exitCode] = await Promise.all([proc.stdout.text(), proc.stderr.text(), proc.exited])
+const output = stdout + stderr
+if (exitCode !== 0) {
+  process.stdout.write(stdout)
+  process.stderr.write(stderr)
+  process.exit(exitCode)
+}
+
+const summary = output.match(/Summary:\s+(.+\.json)/)?.[1]?.trim()
+if (!summary) {
+  process.stdout.write(stdout)
+  process.stderr.write(stderr)
+  throw new Error("Turbo did not report a run summary")
+}
+
+const report = (await Bun.file(summary).json()) as {
+  tasks: Array<{
+    taskId: string
+    execution: { startTime: number; endTime: number; exitCode: number } | null
+  }>
+}
+const tasks = report.tasks
+  .flatMap((task) =>
+    task.execution
+      ? [
+          {
+            task: task.taskId.replace(/#typecheck$/, ""),
+            durationMs: task.execution.endTime - task.execution.startTime,
+          },
+        ]
+      : [],
+  )
+  .sort((a, b) => b.durationMs - a.durationMs)
+const total = tasks.reduce((duration, task) => duration + task.durationMs, 0)
+const width = Math.max(...tasks.map((task) => task.task.length), "Package".length)
+
+console.log(`Package${" ".repeat(width - "Package".length)}  Time    Share`)
+tasks.forEach((task) => {
+  const duration = `${(task.durationMs / 1000).toFixed(2)}s`.padStart(7)
+  const share = `${((task.durationMs / total) * 100).toFixed(1)}%`.padStart(6)
+  console.log(`${task.task.padEnd(width)}  ${duration}  ${share}`)
+})
+console.log(`\nTotal serial task time: ${(total / 1000).toFixed(2)}s`)
+console.log(`Turbo summary: ${path.relative(root, summary)}`)