Fix retrocompatbility of numversion

We need to be able to handle empty version for tests.

Closes #4420

3 files changed, 60 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 62dd0f1ae..15ba23760 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -9,6 +9,10 @@ Release date: 2021-04-26
 ..
   Put new features and bugfixes here and also in 'doc/whatsnew/2.9.rst'
 
+* numversion tuple contains integers again to fix multiple pylint's plugins that relied on it
+
+  Closes #4420
+
 * Fix false-positive ``too-many-ancestors`` when inheriting from builtin classes,
   especially from the ``collections.abc`` module
 
diff --git a/pylint/__pkginfo__.py b/pylint/__pkginfo__.py
index 8316089ec..1a1d99dd2 100644
--- a/pylint/__pkginfo__.py
+++ b/pylint/__pkginfo__.py
@@ -1,5 +1,6 @@
 # Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 # For details: https://github.com/PyCQA/pylint/blob/master/LICENSE
+from typing import Tuple
 
 from pkg_resources import DistributionNotFound, get_distribution
 
@@ -8,5 +9,32 @@ try:
 except DistributionNotFound:
     __version__ = "2.8.2+"
 
-# Kept for compatibility reason, see https://github.com/PyCQA/pylint/issues/4399
-numversion = tuple(__version__.split("."))
+
+def get_numversion_from_version(v: str) -> Tuple:
+    """Kept for compatibility reason
+
+    See https://github.com/PyCQA/pylint/issues/4399
+    https://github.com/PyCQA/pylint/issues/4420,
+    """
+    v = v.replace("pylint-", "")
+    version = []
+    for n in v.split(".")[0:3]:
+        try:
+            version.append(int(n))
+        except ValueError:
+            num = ""
+            for c in n:
+                if c.isdigit():
+                    num += c
+                else:
+                    break
+            try:
+                version.append(int(num))
+            except ValueError:
+                version.append(0)
+    while len(version) != 3:
+        version.append(0)
+    return tuple(version)
+
+
+numversion = get_numversion_from_version(__version__)
diff --git a/tests/test_numversion.py b/tests/test_numversion.py
new file mode 100644
index 000000000..d1f459a5a
--- /dev/null
+++ b/tests/test_numversion.py
@@ -0,0 +1,26 @@
+# Licensed under the GPL: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html
+# For details: https://github.com/PyCQA/pylint/blob/master/LICENSE
+
+import pytest
+
+from pylint.__pkginfo__ import get_numversion_from_version
+
+
+@pytest.mark.parametrize(
+    "version,expected_numversion",
+    [
+        ["2.8.1", (2, 8, 1)],
+        ["2.8.2+", (2, 8, 2)],
+        ["3.0.0a0", (3, 0, 0)],
+        ["3..0", (3, 0, 0)],
+        ["1.a", (1, 0, 0)],
+        ["", (0, 0, 0)],
+        ["3.0.0b1", (3, 0, 0)],
+        ["3.0.0rc1", (3, 0, 0)],
+        ["3.0.0dev-234324234234f23abc4", (3, 0, 0)],
+        ["pylint-2.4.7", (2, 4, 7)],
+        ["2.8.3.dev3+g28c093c2.d20210428", (2, 8, 3)],
+    ],
+)
+def test_numversion(version, expected_numversion):
+    assert get_numversion_from_version(version) == expected_numversion