fix(tooling): bound formatter arguments for large changed checks (#162703)

Reuse the docs formatter batching owner so changed-file checks retain every selected path without overflowing the pnpm shell command. Preserve formatting flags and serial failure propagation.

Co-authored-by: steipete <58493+steipete@users.noreply.github.com>

scripts/check-changed.mts

@@ -36,6 +36,7 @@ import { getChangedPathFacts, normalizeChangedPath } from "./lib/changed-path-fa
 import { printTimingSummary } from "./lib/check-timing-summary.mts";
 import { isDirectRunUrl } from "./lib/direct-run.mjs";
 import { runWithFailedTrailer } from "./lib/failed-trailer.mts";
+import { chunkFormatFilesForCommand } from "./lib/format-command-batches.mts";
 import { resolveLocalCheckEnv } from "./lib/local-check-runtime.mts";
 import { runManagedCommand } from "./lib/managed-child-process.mts";
 import { readNativeTypeScriptConfig } from "./lib/native-typescript-config.mts";
@@ -785,15 +786,9 @@ export function createChangedCheckPlan(
   add("duplicate scan target coverage", ["dup:check:coverage"]);
   broadAudits.add(add("coercion helper declaration guard", ["check:coercion-helpers"]));
   add("dependency pin guard", ["deps:pins:check"]);
-  if (result.paths.length > 0) {
-    lintChecks.add(
-      add("format changed files", [
-        "format:check",
-        "--no-error-on-unmatched-pattern",
-        "--",
-        ...result.paths,
-      ]),
-    );
+  const formatPrefix = ["format:check", "--no-error-on-unmatched-pattern", "--"];
+  for (const files of chunkFormatFilesForCommand(result.paths, formatPrefix)) {
+    lintChecks.add(add("format changed files", [...formatPrefix, ...files]));
   }
   const npmLockGuardCommand = createNpmLockGuardCommand(result.paths);
   if (npmLockGuardCommand) {

scripts/format-docs.mts

@@ -6,6 +6,10 @@ import fs from "node:fs";
 import os from "node:os";
 import path from "node:path";
 import { pathToFileURL } from "node:url";
+import {
+  chunkFormatFilesForCommand,
+  FORMAT_MAX_COMMAND_LINE_BYTES,
+} from "./lib/format-command-batches.mts";
 import { resolveRepoToolBinPath } from "./lib/local-check-runtime.mts";
 import { outputTail, spawnOutputText } from "./lib/output-tail.mts";
 import { resolveRepoRoot } from "./lib/repo-root.mjs";
@@ -13,7 +17,6 @@ import { buildCmdExeCommandLine, resolveWindowsCmdExePath } from "./windows-cmd-
 const ROOT = resolveRepoRoot(import.meta.url);
 const CHECK = process.argv.includes("--check");
 const DOCS_FORMAT_MAX_BUFFER_BYTES = 1024 * 1024 * 16;
-const DOCS_FORMAT_MAX_COMMAND_LINE_BYTES = 24 * 1024;
 const FAILURE_OUTPUT_TAIL_BYTES = 16 * 1024;
 
 type CommandResult = {
@@ -91,37 +94,6 @@ export function docsFiles(root = ROOT, deps: FormatDeps = {}) {
     .filter((relativePath) => (deps.existsSync ?? fs.existsSync)(path.join(root, relativePath)));
 }
 
-function commandLineBytes(args: string[]) {
-  return args.reduce((total, arg) => total + Buffer.byteLength(arg, "utf8") + 3, 0);
-}
-
-function chunkFilesForCommand(
-  files: string[],
-  prefixArgs: string[],
-  maxBytes = DOCS_FORMAT_MAX_COMMAND_LINE_BYTES,
-) {
-  const chunks: string[][] = [];
-  let chunk: string[] = [];
-  let chunkBytes = commandLineBytes(prefixArgs);
-
-  for (const file of files) {
-    const fileBytes = Buffer.byteLength(file, "utf8") + 3;
-    if (chunk.length > 0 && chunkBytes + fileBytes > maxBytes) {
-      chunks.push(chunk);
-      chunk = [];
-      chunkBytes = commandLineBytes(prefixArgs);
-    }
-    chunk.push(file);
-    chunkBytes += fileBytes;
-  }
-
-  if (chunk.length > 0) {
-    chunks.push(chunk);
-  }
-
-  return chunks;
-}
-
 export function resolveOxfmtInvocation(args: string[], params: OxfmtParams = {}) {
   const repoRoot = params.repoRoot ?? ROOT;
   const platform = params.platform ?? process.platform;
@@ -160,10 +132,10 @@ export function runOxfmt(files: string[], params: OxfmtParams = {}, deps: Format
   const repoRoot = params.repoRoot ?? ROOT;
   const spawnSyncImpl = deps.spawnSync ?? spawnSync;
   const prefixArgs = ["--write", "--threads=1", "--config", path.join(repoRoot, ".oxfmtrc.jsonc")];
-  for (const chunk of chunkFilesForCommand(
+  for (const chunk of chunkFormatFilesForCommand(
     files,
     prefixArgs,
-    params.maxCommandLineBytes ?? DOCS_FORMAT_MAX_COMMAND_LINE_BYTES,
+    params.maxCommandLineBytes ?? FORMAT_MAX_COMMAND_LINE_BYTES,
   )) {
     const invocation = resolveOxfmtInvocation([...prefixArgs, ...chunk], {
       comSpec: params.comSpec,

scripts/lib/format-command-batches.mts

@@ -0,0 +1,33 @@
+// Keep formatter arguments bounded even when pnpm joins them into one shell command.
+export const FORMAT_MAX_COMMAND_LINE_BYTES = 24 * 1024;
+
+function commandLineBytes(args: string[]) {
+  return args.reduce((total, arg) => total + Buffer.byteLength(arg, "utf8") + 3, 0);
+}
+
+export function chunkFormatFilesForCommand(
+  files: string[],
+  prefixArgs: string[],
+  maxBytes = FORMAT_MAX_COMMAND_LINE_BYTES,
+) {
+  const chunks: string[][] = [];
+  let chunk: string[] = [];
+  let chunkBytes = commandLineBytes(prefixArgs);
+
+  for (const file of files) {
+    const fileBytes = Buffer.byteLength(file, "utf8") + 3;
+    if (chunk.length > 0 && chunkBytes + fileBytes > maxBytes) {
+      chunks.push(chunk);
+      chunk = [];
+      chunkBytes = commandLineBytes(prefixArgs);
+    }
+    chunk.push(file);
+    chunkBytes += fileBytes;
+  }
+
+  if (chunk.length > 0) {
+    chunks.push(chunk);
+  }
+
+  return chunks;
+}

test/scripts/changed-lanes.format-argv.test.ts

@@ -0,0 +1,27 @@
+import { expect, it } from "vitest";
+import { detectChangedLanes } from "../../scripts/changed-lanes.mts";
+import { createChangedCheckPlan } from "../../scripts/check-changed.mts";
+
+it.each([false, true])(
+  "keeps every formatter path within the argv budget (lintOnly=%s)",
+  (lintOnly) => {
+    const paths = Array.from(
+      { length: 1_600 },
+      (_, index) => `docs/${"long目录_".repeat(8)}file-${index} name's.md`,
+    ).toSorted((left, right) => left.localeCompare(right));
+    const commands = createChangedCheckPlan(detectChangedLanes(paths), {
+      lintOnly,
+    }).commands.filter((command) => command.args[0] === "format:check");
+
+    expect(commands.length).toBeGreaterThan(1);
+    expect(commands.flatMap((command) => command.args.slice(3))).toEqual(paths);
+    for (const command of commands) {
+      expect(command.args.slice(0, 3)).toEqual([
+        "format:check",
+        "--no-error-on-unmatched-pattern",
+        "--",
+      ]);
+      expect(Buffer.byteLength(command.args.join(" "), "utf8")).toBeLessThanOrEqual(24 * 1024);
+    }
+  },
+);