ci: keep gateway watch skip-build artifact fresh

scripts/check-gateway-watch-regression.mjs

@@ -95,6 +95,17 @@ function removePathIfExists(targetPath) {
   fs.rmSync(targetPath, { recursive: true, force: true });
 }
 
+function lstatIfExists(targetPath) {
+  try {
+    return fs.lstatSync(targetPath);
+  } catch (error) {
+    if (error?.code === "ENOENT") {
+      return null;
+    }
+    throw error;
+  }
+}
+
 function normalizePath(filePath) {
   return filePath.replaceAll("\\", "/");
 }
@@ -112,7 +123,15 @@ function listTreeEntries(rootName) {
     if (!current) {
       continue;
     }
-    const dirents = fs.readdirSync(current, { withFileTypes: true });
+    let dirents;
+    try {
+      dirents = fs.readdirSync(current, { withFileTypes: true });
+    } catch (error) {
+      if (error?.code === "ENOENT") {
+        continue;
+      }
+      throw error;
+    }
     for (const dirent of dirents) {
       const fullPath = path.join(current, dirent.name);
       const relativePath = normalizePath(path.relative(process.cwd(), fullPath));
@@ -159,7 +178,10 @@ function snapshotTree(rootName) {
     if (!current) {
       continue;
     }
-    const currentStats = fs.lstatSync(current);
+    const currentStats = lstatIfExists(current);
+    if (!currentStats) {
+      continue;
+    }
     stats.entries += 1;
     if (currentStats.isDirectory()) {
       stats.directories += 1;
@@ -579,6 +601,14 @@ function buildRunNodeDeps(env) {
   };
 }
 
+export function shouldRefreshBuildStampForRestoredArtifacts(params) {
+  return (
+    params.skipBuild === true &&
+    params.buildRequirement?.shouldBuild === true &&
+    params.buildRequirement.reason === "config_newer"
+  );
+}
+
 async function main() {
   const options = parseArgs(process.argv.slice(2));
   ensureDir(options.outputDir);
@@ -594,7 +624,19 @@ async function main() {
     writeBuildStamp({ cwd: process.cwd() });
   }
 
-  const preflightBuildRequirement = resolveBuildRequirement(buildRunNodeDeps(process.env));
+  let preflightBuildRequirement = resolveBuildRequirement(buildRunNodeDeps(process.env));
+  if (
+    shouldRefreshBuildStampForRestoredArtifacts({
+      skipBuild: options.skipBuild,
+      buildRequirement: preflightBuildRequirement,
+    })
+  ) {
+    // CI's skip-build path restores a built dist artifact after checkout.
+    // Refresh the stamp so checkout mtimes for package/config files do not
+    // force a duplicate build during the bounded gateway:watch window.
+    writeBuildStamp({ cwd: process.cwd() });
+    preflightBuildRequirement = resolveBuildRequirement(buildRunNodeDeps(process.env));
+  }
   if (
     preflightBuildRequirement.shouldBuild &&
     preflightBuildRequirement.reason === "dirty_watched_tree"