pyoxidizer: default to one-file binary on non-Windows platforms

Windows has some extra constraints that require a multi-file install,
but we expect folks to use an MSI or similar installer there so it's
less of a big deal.

Differential Revision: https://phab.mercurial-scm.org/D9289

rust/hgcli/pyoxidizer.bzl

@@ -1,108 +1,112 b''
 ROOT = CWD + "/../.."
 
 IS_WINDOWS = "windows" in BUILD_TARGET_TRIPLE
 
 # Code to run in Python interpreter.
 RUN_CODE = "import hgdemandimport; hgdemandimport.enable(); from mercurial import dispatch; dispatch.run()"
 
 set_build_path(ROOT + "/build/pyoxidizer")
 
 def make_distribution():
     return default_python_distribution()
 
 def make_distribution_windows():
     return default_python_distribution(flavor = "standalone_dynamic")
 
 def resource_callback(policy, resource):
+    if not IS_WINDOWS:
+        resource.add_location = "in-memory"
+        return
     # We use a custom resource routing policy to influence where things are loaded
     # from.
     #
     # For Python modules and resources, we load from memory if they are in
     # the standard library and from the filesystem if not. This is because
     # parts of Mercurial and some 3rd party packages aren't yet compatible
     # with memory loading.
     #
     # For Python extension modules, we load from the filesystem because
     # this yields greatest compatibility.
     if type(resource) in ("PythonModuleSource", "PythonPackageResource", "PythonPackageDistributionResource"):
         if resource.is_stdlib:
             resource.add_location = "in-memory"
         else:
             resource.add_location = "filesystem-relative:lib"
 
     elif type(resource) == "PythonExtensionModule":
         resource.add_location = "filesystem-relative:lib"
 
 def make_exe(dist):
     """Builds a Rust-wrapped Mercurial binary."""
     packaging_policy = dist.make_python_packaging_policy()
     # Extension may depend on any Python functionality. Include all
     # extensions.
     packaging_policy.extension_module_filter = "all"
     packaging_policy.resources_location = "in-memory"
-    packaging_policy.resources_location_fallback = "filesystem-relative:lib"
+    if IS_WINDOWS:
+        packaging_policy.resources_location_fallback = "filesystem-relative:lib"
     packaging_policy.register_resource_callback(resource_callback)
 
     config = dist.make_python_interpreter_config()
     config.raw_allocator = "system"
     config.run_mode = "eval:%s" % RUN_CODE
     # We want to let the user load extensions from the file system
     config.filesystem_importer = True
     # We need this to make resourceutil happy, since it looks for sys.frozen.
     config.sys_frozen = True
     config.legacy_windows_stdio = True
 
     exe = dist.to_python_executable(
         name = "hg",
         packaging_policy = packaging_policy,
         config = config,
     )
 
     # Add Mercurial to resources.
     exe.add_python_resources(exe.pip_install(["--verbose", ROOT]))
 
     # On Windows, we install extra packages for convenience.
     if IS_WINDOWS:
         exe.add_python_resources(
             exe.pip_install(["-r", ROOT + "/contrib/packaging/requirements-windows-py2.txt"]),
         )
 
     return exe
 
 def make_manifest(dist, exe):
     m = FileManifest()
     m.add_python_resource(".", exe)
 
     return m
 
 def make_embedded_resources(exe):
     return exe.to_embedded_resources()
 
 register_target("distribution_posix", make_distribution)
 register_target("distribution_windows", make_distribution_windows)
 
 register_target("exe_posix", make_exe, depends = ["distribution_posix"])
 register_target("exe_windows", make_exe, depends = ["distribution_windows"])
 
 register_target(
     "app_posix",
     make_manifest,
     depends = ["distribution_posix", "exe_posix"],
     default = "windows" not in BUILD_TARGET_TRIPLE,
 )
 register_target(
     "app_windows",
     make_manifest,
     depends = ["distribution_windows", "exe_windows"],
     default = "windows" in BUILD_TARGET_TRIPLE,
 )
 
 resolve_targets()
 
 # END OF COMMON USER-ADJUSTED SETTINGS.
 #
 # Everything below this is typically managed by PyOxidizer and doesn't need
 # to be updated by people.
 
 PYOXIDIZER_VERSION = "0.9.0"
 PYOXIDIZER_COMMIT = "1fbc264cc004226cd76ee452e0a386ffca6ccfb1"