Bug 1779937 - Add mach xpcshell r=ahal,nalexander

Differential Revision: https://phabricator.services.mozilla.com/D151984

build/mach_initialize.py

@@ -359,6 +359,7 @@ def initialize(topsrcdir):
             "testing/webcompat/mach_commands.py"
         ),
         "esmify": MachCommandReference("tools/esmify/mach_commands.py"),
+        "xpcshell": MachCommandReference("js/xpconnect/mach_commands.py"),
     }
 
     # Set a reasonable limit to the number of open files.

js/xpconnect/mach_commands.py

@@ -0,0 +1,43 @@
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import argparse
+import sys
+from pathlib import Path
+
+from mach.decorators import (
+    Command,
+    CommandArgument,
+)
+
+
+@Command("xpcshell", category="misc", description="Run the xpcshell binary")
+@CommandArgument(
+    "args", nargs=argparse.REMAINDER, help="Arguments to provide to xpcshell"
+)
+def xpcshell(command_context, args):
+    dist_bin = Path(command_context._topobjdir, "dist", "bin")
+    browser_dir = dist_bin / "browser"
+
+    if sys.platform == "win32":
+        xpcshell = dist_bin / "xpcshell.exe"
+    else:
+        xpcshell = dist_bin / "xpcshell"
+
+    command = [
+        str(xpcshell),
+        "-g",
+        str(dist_bin),
+        "-a",
+        str(browser_dir),
+    ]
+
+    if args:
+        command.extend(args)
+
+    return command_context.run_process(
+        command,
+        pass_thru=True,
+        ensure_exit_code=False,
+    )