Bug 1753375 - Disallow PathUtils.get*Dir on main thread r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D140145

dom/chrome-webidl/PathUtils.webidl

@@ -103,17 +103,26 @@ namespace PathUtils {
 
 [Exposed=Window]
 partial namespace PathUtils {
+  /**
+   * The profile directory.
+   */
   [Throws, BinaryName="ProfileDirSync"]
   readonly attribute DOMString profileDir;
 
+  /**
+   * The local-specific profile directory.
+   */
   [Throws, BinaryName="LocalProfileDirSync"]
   readonly attribute DOMString localProfileDir;
 
+  /**
+   * The temporary directory for the process.
+   */
   [Throws, BinaryName="TempDirSync"]
   readonly attribute DOMString tempDir;
 };
 
-[Exposed=(Window, Worker)]
+[Exposed=Worker]
 partial namespace PathUtils {
   /**
    * The profile directory.

dom/system/PathUtils.cpp

@@ -376,7 +376,7 @@ void PathUtils::GetTempDirSync(const GlobalObject&, nsString& aResult,
 
 already_AddRefed<Promise> PathUtils::GetProfileDirAsync(
     const GlobalObject& aGlobal, ErrorResult& aErr) {
-  // NB: This will eventually be off-main-thread only.
+  MOZ_ASSERT(!NS_IsMainThread());
 
   auto guard = sDirCache.Lock();
   return DirectoryCache::Ensure(guard.ref())
@@ -385,7 +385,7 @@ already_AddRefed<Promise> PathUtils::GetProfileDirAsync(
 
 already_AddRefed<Promise> PathUtils::GetLocalProfileDirAsync(
     const GlobalObject& aGlobal, ErrorResult& aErr) {
-  // NB: This will eventually be off-main-thread only.
+  MOZ_ASSERT(!NS_IsMainThread());
 
   auto guard = sDirCache.Lock();
   return DirectoryCache::Ensure(guard.ref())
@@ -395,7 +395,7 @@ already_AddRefed<Promise> PathUtils::GetLocalProfileDirAsync(
 
 already_AddRefed<Promise> PathUtils::GetTempDirAsync(
     const GlobalObject& aGlobal, ErrorResult& aErr) {
-  // NB: This will eventually be off-main-thread only.
+  MOZ_ASSERT(!NS_IsMainThread());
 
   auto guard = sDirCache.Lock();
   return DirectoryCache::Ensure(guard.ref())

dom/system/tests/test_pathutils.html

@@ -318,7 +318,7 @@
       // symlink to `/var`, so we need to pre-normalize our temporary directory
       // or expected paths won't match.
       const tmpDir = PathUtils.join(
-        PathUtils.normalize(await PathUtils.getTempDir()),
+        PathUtils.normalize(PathUtils.tempDir),
         "pathutils_test"
       );
 
@@ -475,19 +475,16 @@
   add_task(async function test_getDirectories() {
     // See: nsAppDirectoryServiceDefs.h
     const tests = [
-      ["profileDir", "getProfileDir", "ProfD"],
-      ["localProfileDir", "getLocalProfileDir", "ProfLD"],
-      ["tempDir", "getTempDir", AppConstants.MOZ_SANDBOX ? "ContentTmpD" : "TmpD"],
+      ["profileDir", "ProfD"],
+      ["localProfileDir", "ProfLD"],
+      ["tempDir", AppConstants.MOZ_SANDBOX ? "ContentTmpD" : "TmpD"],
     ];
 
-    for (const [attrName, methName, dirConstant] of tests) {
+    for (const [attrName, dirConstant] of tests) {
       const expected = Services.dirsvc.get(dirConstant, Ci.nsIFile).path;
 
       const attrValue = PathUtils[attrName];
       is(attrValue, expected, `PathUtils.${attrName} == Services.dirsvc.get("${dirConstant}", Ci.nsIFile).path`);
-
-      const methValue = await PathUtils[methName]();
-      is(methValue, expected, `PathUtils.${methName}() == Services.dirsvc.get("${dirConstant}", Ci.nsIFile).path`);
     }
   });
 </script>