Add QUTE_QTWEBENGINE_VERSION_OVERRIDE

See https://github.com/NixOS/nixpkgs/pull/119376#issuecomment-820073044

(cherry picked from commit febb921040b6670d9b1694a6ce55ae39384d1306)

2 files changed, 16 insertions, 2 deletions

diff --git a/qutebrowser/utils/version.py b/qutebrowser/utils/version.py
index 2bac125ed..f5bc5eab2 100644
--- a/qutebrowser/utils/version.py
+++ b/qutebrowser/utils/version.py
@@ -710,7 +710,7 @@ class WebEngineVersions:
         )
 
     @classmethod
-    def from_qt(cls, qt_version: str) -> 'WebEngineVersions':
+    def from_qt(cls, qt_version: str, *, source: str = 'Qt') -> 'WebEngineVersions':
         """Get the versions based on the Qt version.
 
         This is called if we don't have PYQT_WEBENGINE_VERSION, i.e. with PyQt 5.12.
@@ -719,7 +719,7 @@ class WebEngineVersions:
         return cls(
             webengine=parsed,
             chromium=cls._infer_chromium_version(parsed),
-            source='Qt',
+            source=source,
         )
 
 
@@ -750,6 +750,10 @@ def qtwebengine_versions(avoid_init: bool = False) -> WebEngineVersions:
     if webenginesettings.parsed_user_agent is not None:
         return WebEngineVersions.from_ua(webenginesettings.parsed_user_agent)
 
+    override = os.environ.get('QUTE_QTWEBENGINE_VERSION_OVERRIDE')
+    if override is not None:
+        return WebEngineVersions.from_qt(override, source='override')
+
     versions = elf.parse_webenginecore()
     if versions is not None:
         return WebEngineVersions.from_elf(versions)
diff --git a/tests/unit/utils/test_version.py b/tests/unit/utils/test_version.py
index b50352e34..734b70468 100644
--- a/tests/unit/utils/test_version.py
+++ b/tests/unit/utils/test_version.py
@@ -1174,6 +1174,16 @@ class TestChromiumVersion:
         assert versions.source == 'importlib'
         assert versions.webengine == expected
 
+    @pytest.mark.parametrize('override', [
+        utils.VersionNumber(5, 12, 10),
+        utils.VersionNumber(5, 15, 3),
+    ])
+    def test_override(self, monkeypatch, override):
+        monkeypatch.setenv('QUTE_QTWEBENGINE_VERSION_OVERRIDE', str(override))
+        versions = version.qtwebengine_versions(avoid_init=True)
+        assert versions.source == 'override'
+        assert versions.webengine == override
+
 
 @dataclasses.dataclass
 class VersionParams: