From c326a9f02a23b1feecae3491003b727602ce652f Mon Sep 17 00:00:00 2001
From: Christopher Davies <github@christophilus.com>
Date: Fri, 10 Jan 2020 09:22:29 -0500
Subject: [PATCH 1/3] Fix a stack overflow with watch_cache when it attempts to
 delete very large folders.

---
 src/optimize/watch/watch_cache.ts | 38 ++++++++++++++++++++++++++-----
 1 file changed, 32 insertions(+), 6 deletions(-)

diff --git a/src/optimize/watch/watch_cache.ts b/src/optimize/watch/watch_cache.ts
index ab11a8c5d2f118..de6466aa76d796 100644
--- a/src/optimize/watch/watch_cache.ts
+++ b/src/optimize/watch/watch_cache.ts
@@ -18,17 +18,18 @@
  */
 
 import { createHash } from 'crypto';
-import { readFile, writeFile } from 'fs';
+import { readFile, writeFile, readdir, unlink, rmdir } from 'fs';
 import { resolve } from 'path';
 import { promisify } from 'util';
-
+import path from 'path';
 import del from 'del';
-import deleteEmpty from 'delete-empty';
-import globby from 'globby';
 import normalizePosixPath from 'normalize-path';
 
 const readAsync = promisify(readFile);
 const writeAsync = promisify(writeFile);
+const readdirAsync = promisify(readdir);
+const unlinkAsync = promisify(unlink);
+const rmdirAsync = promisify(rmdir);
 
 interface Params {
   logWithMetadata: (tags: string[], message: string, metadata?: { [key: string]: any }) => void;
@@ -95,11 +96,11 @@ export class WatchCache {
     await del(this.statePath, { force: true });
 
     // delete everything in optimize/.cache directory
-    await del(await globby([normalizePosixPath(this.cachePath)], { dot: true }));
+    await recursiveDelete(normalizePosixPath(this.cachePath));
 
     // delete some empty folder that could be left
     // from the previous cache path reset action
-    await deleteEmpty(this.cachePath);
+    // await deleteEmpty(this.cachePath);
 
     // delete dlls
     await del(this.dllsPath);
@@ -167,3 +168,28 @@ export class WatchCache {
     }
   }
 }
+
+/**
+ * Recursively deletes a folder. This is a workaround for a bug in `del` where
+ * very large folders (with 84K+ files) cause a stack overflow.
+ */
+async function recursiveDelete(directory: string) {
+  const entries = await readdirAsync(directory, { withFileTypes: true });
+  await Promise.all(
+    entries.map(entry => {
+      const absolutePath = path.join(directory, entry.name);
+      const result = entry.isDirectory()
+        ? recursiveDelete(absolutePath)
+        : unlinkAsync(absolutePath);
+
+      // Ignore errors, if the file or directory doesn't exist.
+      result.catch(e => {
+        if (e.code !== 'ENOENT') {
+          throw e;
+        }
+      });
+    })
+  );
+
+  return rmdirAsync(directory);
+}

From 7a6b5f3fe3a684c7c8bb408d26976ee8b72db8be Mon Sep 17 00:00:00 2001
From: Christopher Davies <github@christophilus.com>
Date: Fri, 10 Jan 2020 09:29:55 -0500
Subject: [PATCH 2/3] Remove unused code

---
 src/optimize/watch/watch_cache.ts | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/optimize/watch/watch_cache.ts b/src/optimize/watch/watch_cache.ts
index de6466aa76d796..8288ccc88e57d9 100644
--- a/src/optimize/watch/watch_cache.ts
+++ b/src/optimize/watch/watch_cache.ts
@@ -98,10 +98,6 @@ export class WatchCache {
     // delete everything in optimize/.cache directory
     await recursiveDelete(normalizePosixPath(this.cachePath));
 
-    // delete some empty folder that could be left
-    // from the previous cache path reset action
-    // await deleteEmpty(this.cachePath);
-
     // delete dlls
     await del(this.dllsPath);
 

From 2c02e9e39c1b210a1c101a5e5018b61218acf5a8 Mon Sep 17 00:00:00 2001
From: Christopher Davies <github@christophilus.com>
Date: Fri, 10 Jan 2020 10:01:35 -0500
Subject: [PATCH 3/3] Fix reursiveDelete promise handling bug

---
 src/optimize/watch/watch_cache.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/optimize/watch/watch_cache.ts b/src/optimize/watch/watch_cache.ts
index 8288ccc88e57d9..15957210b3d43c 100644
--- a/src/optimize/watch/watch_cache.ts
+++ b/src/optimize/watch/watch_cache.ts
@@ -179,7 +179,7 @@ async function recursiveDelete(directory: string) {
         : unlinkAsync(absolutePath);
 
       // Ignore errors, if the file or directory doesn't exist.
-      result.catch(e => {
+      return result.catch(e => {
         if (e.code !== 'ENOENT') {
           throw e;
         }