Fix issues with locale workaround

qutebrowser/config/qtargs.py

@@ -165,6 +165,30 @@ def _get_locale_pak_path(locales_path: pathlib.Path, locale_name: str) -> pathli
     return locales_path / (locale_name + '.pak')
 
 
+def _get_pak_name(locale_name: str) -> str:
+    """Get the Chromium .pak name for a locale name.
+
+    Based on Chromium's behavior in l10n_util::CheckAndResolveLocale:
+    https://source.chromium.org/chromium/chromium/src/+/master:ui/base/l10n/l10n_util.cc;l=344-428;drc=43d5378f7f363dab9271ca37774c71176c9e7b69
+    """
+    if locale_name in {'en', 'en-PH', 'en-LR'}:
+        return 'en-US'
+    elif locale_name.startswith('en-'):
+        return 'en-GB'
+    elif locale_name.startswith('es-'):
+        return 'es-419'
+    elif locale_name == 'pt':
+        return 'pt-BR'
+    elif locale_name.startswith('pt-'):  # pragma: no cover
+        return 'pt-PT'
+    elif locale_name in {'zh-HK', 'zh-MO'}:
+        return 'zh-TW'
+    elif locale_name == 'zh' or locale_name.startswith('zh-'):
+        return 'zh-CN'
+
+    return locale_name.split('-')[0]
+
+
 def _get_lang_override(
         webengine_version: utils.VersionNumber,
         locale_name: str
@@ -191,25 +215,7 @@ def _get_lang_override(
         log.init.debug(f"Found {pak_path}, skipping workaround")
         return None
 
-    # Based on Chromium's behavior in l10n_util::CheckAndResolveLocale:
-    # https://source.chromium.org/chromium/chromium/src/+/master:ui/base/l10n/l10n_util.cc;l=344-428;drc=43d5378f7f363dab9271ca37774c71176c9e7b69
-    if locale_name in {'en', 'en-PH', 'en-LR'}:
-        pak_name = 'en-US'
-    elif locale_name.startswith('en-'):
-        pak_name = 'en-GB'
-    elif locale_name.startswith('es-'):
-        pak_name = 'es-419'
-    elif locale_name == 'pt':
-        pak_name = 'pt-BR'
-    elif locale_name.startswith('pt-'):
-        pak_name = 'pt-PT'
-    elif locale_name in {'zh-HK', 'zh-MO'}:
-        pak_name = 'zh-TW'
-    elif locale_name == 'zh' or locale_name.startswith('zh-'):
-        pak_name = 'zh-CN'
-    else:
-        pak_name = locale_name.split('-')[0]
-
+    pak_name = _get_pak_name(locale_name)
     pak_path = _get_locale_pak_path(locales_path, pak_name)
     if pak_path.exists():
         log.init.debug(f"Found {pak_path}, applying workaround")

tests/unit/config/test_qtargs.py

@@ -530,6 +530,22 @@ class TestWebEngineArgs:
         for arg in expected:
             assert arg in args
 
+    @pytest.mark.linux
+    def test_locale_workaround(self, config_stub, monkeypatch, version_patcher,
+                               parser):
+        class FakeLocale:
+
+            def bcp47Name(self):
+                return 'de-CH'
+
+        monkeypatch.setattr(qtargs.objects, 'backend', usertypes.Backend.QtWebEngine)
+        monkeypatch.setattr(qtargs, 'QLocale', FakeLocale)
+        version_patcher('5.15.3')
+        config_stub.val.qt.workarounds.locale = True
+        parsed = parser.parse_args([])
+        args = qtargs.qt_args(parsed)
+        assert '--lang=de' in args
+
 
 class TestEnvVars:
 

tests/unit/config/test_qtargs_locale_workaround.py

@@ -403,6 +403,7 @@ def qtwe_version():
     ("zh_XX.UTF-8", "zh-CN"),  # locale not available on my system
     ("zu_ZA.UTF-8", "en-US"),
 ])
+@pytest.mark.linux
 def test_lang_workaround_all_locales(lang, expected, qtwe_version):
     locale_name = QLocale(lang).bcp47Name()
     print(locale_name)
@@ -444,3 +445,11 @@ def test_non_linux(qtwe_version):
 def test_disabled(qtwe_version, config_stub):
     config_stub.val.qt.workarounds.locale = False
     assert qtargs._get_lang_override(qtwe_version, "de-CH") is None
+
+
+@pytest.mark.fake_os('linux')
+def test_no_locales_available(qtwe_version, monkeypatch, caplog):
+    monkeypatch.setattr(qtargs.QLibraryInfo, 'location', lambda _path: '/doesnotexist')
+    assert qtargs._get_lang_override(qtwe_version, "de-CH") is None
+    assert caplog.messages == [
+        "/doesnotexist/qtwebengine_locales not found, skipping workaround!"]