fix hot/hot.test.ts, hot/watch.test.ts, and watch/watch.test.ts (#13876)

Co-authored-by: dylan-conway <dylan-conway@users.noreply.github.com>

test/cli/hot/hot.test.ts

@@ -1,7 +1,7 @@
 import { spawn } from "bun";
 import { beforeEach, expect, it } from "bun:test";
 import { copyFileSync, cpSync, readFileSync, renameSync, rmSync, unlinkSync, writeFileSync } from "fs";
-import { bunEnv, bunExe, isDebug, tmpdirSync } from "harness";
+import { bunEnv, bunExe, isDebug, tmpdirSync, waitForFileToExist } from "harness";
 import { join } from "path";
 
 const timeout = isDebug ? Infinity : 10_000;
@@ -487,6 +487,7 @@ throw new Error('0');`,
       stderr: "inherit",
       stdin: "ignore",
     });
+    waitForFileToExist(hotRunnerRoot, 20);
     await using runner = spawn({
       cmd: [bunExe(), "--hot", "run", hotRunnerRoot],
       env: bunEnv,
@@ -576,6 +577,7 @@ throw new Error('0');`,
       stderr: "ignore",
       stdin: "ignore",
     });
+    waitForFileToExist(hotRunnerRoot, 20);
     await using runner = spawn({
       cmd: [
         //

test/cli/watch/watch.test.ts

@@ -35,7 +35,7 @@ for (const dir of ["dir", "©️"]) {
       await updateFile(i);
     }
     rmSync(path);
-  });
+  }, 10000);
 }
 
 afterEach(() => {

test/harness.ts

@@ -1,4 +1,4 @@
-import { gc as bunGC, spawnSync, unsafe, which } from "bun";
+import { gc as bunGC, sleepSync, spawnSync, unsafe, which } from "bun";
 import { heapStats } from "bun:jsc";
 import { afterAll, beforeAll, describe, expect, test } from "bun:test";
 import { readFile, readlink, writeFile } from "fs/promises";
@@ -1284,3 +1284,9 @@ Object.defineProperty(globalThis, "gc", {
   enumerable: false,
   configurable: true,
 });
+
+export function waitForFileToExist(path: string, interval: number) {
+  while (!fs.existsSync(path)) {
+    sleepSync(interval);
+  }
+}