Bug 1822873 - Avoid mainthread IO in PathUtils.toFileURI r=Gijs

Differential Revision: https://phabricator.services.mozilla.com/D173330

dom/system/PathUtils.cpp

@@ -28,6 +28,7 @@
 #include "nsLocalFile.h"
 #include "nsNetUtil.h"
 #include "nsString.h"
+#include "nsURLHelper.h"
 #include "xpcpublic.h"
 
 namespace mozilla::dom {
@@ -397,13 +398,8 @@ void PathUtils::ToFileURI(const GlobalObject&, const nsAString& aPath,
     return;
   }
 
-  nsCOMPtr<nsIURI> uri;
-  if (nsresult rv = NS_NewFileURI(getter_AddRefs(uri), path); NS_FAILED(rv)) {
-    ThrowError(aErr, rv, "Could not initialize File URI"_ns);
-    return;
-  }
-
-  if (nsresult rv = uri->GetSpec(aResult); NS_FAILED(rv)) {
+  if (nsresult rv = net_GetURLSpecFromActualFile(path, aResult);
+      NS_FAILED(rv)) {
     ThrowError(aErr, rv, "Could not retrieve URI spec"_ns);
     return;
   }

dom/system/tests/test_pathutils.html

@@ -528,13 +528,13 @@
     if (Services.appinfo.OS === "WINNT") {
       is(
         PathUtils.toFileURI("C:\\"),
-        "file:///C:/",
+        "file:///C:",
         "PathUtils.toFileURI() with a root path"
       );
 
       is(
         PathUtils.toFileURI("C:\\Windows\\"),
-        "file:///C:/Windows/",
+        "file:///C:/Windows",
         "PathUtils.toFileURI() with a non-root directory path"
       );
 
@@ -552,7 +552,7 @@
 
       is(
         PathUtils.toFileURI("/bin"),
-        "file:///bin/",
+        "file:///bin",
         "PathUtils.toFileURI() with a non-root directory path"
       );
 

services/settings/test/unit/test_attachments_downloader.js

@@ -153,7 +153,7 @@ add_task(async function test_download_writes_file_in_profile() {
 
   Assert.equal(
     fileURL,
-    PROFILE_URL + "settings/main/some-collection/test_file.pem"
+    PROFILE_URL + "/settings/main/some-collection/test_file.pem"
   );
   Assert.ok(await IOUtils.exists(localFilePath));
   const stat = await IOUtils.stat(localFilePath);
@@ -292,13 +292,13 @@ add_task(async function test_downloader_is_accessible_via_client() {
 
   Assert.equal(
     fileURL,
-    PROFILE_URL +
-      [
-        "settings",
-        client.bucketName,
-        client.collectionName,
-        RECORD.attachment.filename,
-      ].join("/")
+    [
+      PROFILE_URL,
+      "settings",
+      client.bucketName,
+      client.collectionName,
+      RECORD.attachment.filename,
+    ].join("/")
   );
 });
 add_task(clear_state);