From 4b0382791da283162a8397d308f4dcda9fc6ae20 Mon Sep 17 00:00:00 2001
From: Chris Huber <chris.huber@automattic.com>
Date: Tue, 1 Sep 2026 13:31:40 -0400
Subject: [PATCH] fix(smoke): isolate parallel tsx transforms

---
 scripts/smoke-discovery.ts    |  6 +++---
 tests/smoke-discovery.test.ts | 26 ++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 3 deletions(-)
 create mode 100644 tests/smoke-discovery.test.ts

diff --git a/scripts/smoke-discovery.ts b/scripts/smoke-discovery.ts
index 79808dd5..1f79b0ef 100644
--- a/scripts/smoke-discovery.ts
+++ b/scripts/smoke-discovery.ts
@@ -100,11 +100,11 @@ export function discoverSmokeFiles(root = process.cwd()): string[] {
   return files.filter((file) => !excluded.has(file)).sort()
 }
 
-function toCommand(file: string): SmokeCommand {
+function toCommand(file: string, disableTsxCache = false): SmokeCommand {
   return {
     name: file,
     command: file.endsWith(".php") ? "php" : file.endsWith(".mjs") ? "node" : "tsx",
-    args: [file],
+    args: disableTsxCache && file.endsWith(".ts") ? ["--no-cache", file] : [file],
   }
 }
 
@@ -114,7 +114,7 @@ export function discoveredCommands(root = process.cwd()): SmokeCommand[] {
 
 /** Files safe to run concurrently. */
 export function discoveredParallelCommands(root = process.cwd()): SmokeCommand[] {
-  return discoverSmokeFiles(root).filter((file) => !serial.has(file)).map(toCommand)
+  return discoverSmokeFiles(root).filter((file) => !serial.has(file)).map((file) => toCommand(file, true))
 }
 
 /** Files that must run one at a time, after the parallel phase. */
diff --git a/tests/smoke-discovery.test.ts b/tests/smoke-discovery.test.ts
new file mode 100644
index 00000000..7a918375
--- /dev/null
+++ b/tests/smoke-discovery.test.ts
@@ -0,0 +1,26 @@
+import assert from "node:assert/strict"
+import { mkdir, mkdtemp, rm, writeFile } from "node:fs/promises"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
+
+import { discoveredParallelCommands, discoveredSerialCommands } from "../scripts/smoke-discovery.js"
+
+const root = await mkdtemp(join(tmpdir(), "wp-codebox-smoke-discovery-"))
+
+try {
+  await mkdir(join(root, "tests"))
+  await mkdir(join(root, "scripts"))
+  await writeFile(join(root, "tests", "parallel.test.ts"), "")
+  await writeFile(join(root, "tests", "recipe-step-continuation.integration.test.ts"), "")
+  await writeFile(join(root, "scripts", "native-smoke.php"), "")
+
+  assert.deepEqual(discoveredParallelCommands(root), [
+    { name: "scripts/native-smoke.php", command: "php", args: ["scripts/native-smoke.php"] },
+    { name: "tests/parallel.test.ts", command: "tsx", args: ["--no-cache", "tests/parallel.test.ts"] },
+  ])
+  assert.deepEqual(discoveredSerialCommands(root), [
+    { name: "tests/recipe-step-continuation.integration.test.ts", command: "tsx", args: ["tests/recipe-step-continuation.integration.test.ts"] },
+  ])
+} finally {
+  await rm(root, { recursive: true, force: true })
+}