Handle version numbers with >3 digits

Closes #6354

4 files changed, 16 insertions, 3 deletions

diff --git a/doc/changelog.asciidoc b/doc/changelog.asciidoc
index c94b99a39..dd1e7b86f 100644
--- a/doc/changelog.asciidoc
+++ b/doc/changelog.asciidoc
@@ -123,6 +123,8 @@ Fixed
   workaround which prevents the hang.
 - QtWebEngine version detection (influencing things like dark mode settings or
   certain workarounds) now works correctly on OpenBSD.
+- Certain version number formats in `/etc/os-release` caused qutebrowser to
+  crash. Those are now handled correctly.
 
 Removed
 ~~~~~~~
diff --git a/qutebrowser/utils/utils.py b/qutebrowser/utils/utils.py
index 2a47d60aa..762d2d370 100644
--- a/qutebrowser/utils/utils.py
+++ b/qutebrowser/utils/utils.py
@@ -87,7 +87,7 @@ class VersionNumber:
     """A representation of a version number."""
 
     def __init__(self, *args: int) -> None:
-        self._ver = QVersionNumber(*args)
+        self._ver = QVersionNumber(args)  # not *args, to support >3 components
         if self._ver.isNull():
             raise ValueError("Can't construct a null version")
 
@@ -102,8 +102,6 @@ class VersionNumber:
         self.patch = self._ver.microVersion()
         self.segments = self._ver.segments()
 
-        assert len(self.segments) <= 3, self.segments
-
     def __str__(self) -> str:
         return ".".join(str(s) for s in self.segments)
 
diff --git a/tests/unit/utils/test_utils.py b/tests/unit/utils/test_utils.py
index 734758957..57adc883c 100644
--- a/tests/unit/utils/test_utils.py
+++ b/tests/unit/utils/test_utils.py
@@ -57,6 +57,7 @@ class TestVersionNumber:
         (VersionNumber(5, 15, 2), '5.15.2'),
         (VersionNumber(5, 15), '5.15'),
         (VersionNumber(5), '5'),
+        (VersionNumber(1, 2, 3, 4), '1.2.3.4'),
     ])
     def test_str(self, num, expected):
         assert str(num) == expected
@@ -69,6 +70,7 @@ class TestVersionNumber:
         (VersionNumber(5, 15, 2), VersionNumber(5, 15)),
         (VersionNumber(5, 15), VersionNumber(5, 15)),
         (VersionNumber(6), VersionNumber(6)),
+        (VersionNumber(1, 2, 3, 4), VersionNumber(1, 2)),
     ])
     def test_strip_patch(self, num, expected):
         assert num.strip_patch() == expected
@@ -79,6 +81,7 @@ class TestVersionNumber:
         ('5.15', VersionNumber(5, 15)),
         ('5.15.3', VersionNumber(5, 15, 3)),
         ('5.15.3.dev1234', VersionNumber(5, 15, 3)),
+        ('1.2.3.4', VersionNumber(1, 2, 3, 4)),
     ])
     def test_parse_valid(self, s, expected):
         assert VersionNumber.parse(s) == expected
diff --git a/tests/unit/utils/test_version.py b/tests/unit/utils/test_version.py
index d38671e9e..e79b87794 100644
--- a/tests/unit/utils/test_version.py
+++ b/tests/unit/utils/test_version.py
@@ -259,6 +259,16 @@ except ImportError:
         id='nixos', parsed=version.Distribution.nixos,
         version=utils.VersionNumber(21, 3),
         pretty='NixOS 21.03 (Okapi)')),
+    # NixOS (fake fourth version component)
+    ("""
+        NAME=NixOS
+        ID=nixos
+        VERSION="21.05.20210402.1dead (Okapi)"
+    """,
+    version.DistributionInfo(
+        id='nixos', parsed=version.Distribution.nixos,
+        version=utils.VersionNumber(21, 5, 20210402, 1),
+        pretty='NixOS')),
     # SolusOS
     ("""
         NAME="Solus"