fix: handle None case in xcode_emulation regexes

[aduh95]

In the case where softwareupdate --history does not list any CLT update, the program crashes with an unhelpful error instead of trying the next fallback.

Stacktrace

Traceback (most recent call last):
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 1501, in XcodeVersion
    version_list = GetStdoutQuiet(["xcodebuild", "-version"]).splitlines()
                   ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 1560, in GetStdoutQuiet
    job = subprocess.Popen(cmdlist, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
  File "/nix/store/i8r431v9g2hwh9g0kkp2lrgd426szgnq-python3-3.13.7/lib/python3.13/subprocess.py", line 1039, in __init__
    self._execute_child(args, executable, preexec_fn, close_fds,
    ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
                        pass_fds, cwd, env,
                        ^^^^^^^^^^^^^^^^^^^
    ...<5 lines>...
                        gid, gids, uid, umask,
                        ^^^^^^^^^^^^^^^^^^^^^^
                        start_new_session, process_group)
                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/nix/store/i8r431v9g2hwh9g0kkp2lrgd426szgnq-python3-3.13.7/lib/python3.13/subprocess.py", line 1972, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: 'xcodebuild'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/configure.py", line 2428, in <module>
    run_gyp(gyp_args)
    ~~~~~~~^^^^^^^^^^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp_node.py", line 52, in run_gyp
    rc = gyp.main(args)
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/__init__.py", line 692, in main
    return gyp_main(args)
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/__init__.py", line 677, in gyp_main
    generator.GenerateOutput(flat_list, targets, data, params)
    ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/generator/ninja.py", line 2957, in GenerateOutput
    GenerateOutputForConfig(
    ~~~~~~~~~~~~~~~~~~~~~~~^
        target_list, target_dicts, data, params, config_name
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/generator/ninja.py", line 2829, in GenerateOutputForConfig
    target = writer.WriteSpec(spec, config_name, generator_flags)
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/generator/ninja.py", line 413, in WriteSpec
    self.archs = self.xcode_settings.GetActiveArchs(config_name)
                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 510, in GetActiveArchs
    xcode_archs_default = GetXcodeArchsDefault()
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 120, in GetXcodeArchsDefault
    xcode_version, _ = XcodeVersion()
                       ~~~~~~~~~~~~^^
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 1513, in XcodeVersion
    version = CLTVersion()  # macOS Catalina returns 11.0.0.0.1.1567737322
  File "/private/tmp/nix-build-nodejs-22.19.0.drv-0/node-v22.19.0/tools/gyp/pylib/gyp/xcode_emulation.py", line 1551, in CLTVersion
    return re.search(regex, output).groupdict()["version"]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'groupdict'

[cclauss]

Nice!

Can you please add a sample of the current error stack trace?

Would it be possible to add a pytest so we avoid regressions?

[aduh95]

I've updated the OP with a stacktrace. I don't know about pytest, we would need to mock GetStdout or re.search to return an empty result as I don't think we can tamper with /usr/sbin/softwareupdate output

[cclauss]

Nice! Let's move forward with these changes.