environment: fallback regex for versions like 2020.01

add four-digit version unit_test cases

mesonbuild/environment.py

@@ -347,7 +347,6 @@ def detect_cpu_family(compilers: CompilersDict) -> str:
     elif trial in {'ip30', 'ip35'}:
         trial = 'mips64'
 
-
     # On Linux (and maybe others) there can be any mixture of 32/64 bit code in
     # the kernel, Python, system, 32-bit chroot on 64-bit host, etc. The only
     # reliable way to know is to check the compiler defines.
@@ -443,7 +442,7 @@ def machine_info_can_run(machine_info: MachineInfo):
         (machine_info.cpu_family == true_build_cpu_family) or \
         ((true_build_cpu_family == 'x86_64') and (machine_info.cpu_family == 'x86'))
 
-def search_version(text):
+def search_version(text: str) -> str:
     # Usually of the type 4.1.4 but compiler output may contain
     # stuff like this:
     # (Sourcery CodeBench Lite 2014.05-29) 4.8.3 20140320 (prerelease)
@@ -477,6 +476,13 @@ def search_version(text):
     match = version_regex.search(text)
     if match:
         return match.group(0)
+
+    # try a simpler regex that has like "blah 2020.01.100 foo" or "blah 2020.01 foo"
+    version_regex = re.compile(r"(\d{1,4}\.\d{1,4}\.?\d{0,4})")
+    match = version_regex.search(text)
+    if match:
+        return match.group(0)
+
     return 'unknown version'
 
 class Environment:

run_unittests.py

@@ -40,7 +40,7 @@ from contextlib import contextmanager
 from glob import glob
 from pathlib import (PurePath, Path)
 from distutils.dir_util import copy_tree
-import typing
+import typing as T
 
 import mesonbuild.mlog
 import mesonbuild.depfile
@@ -312,8 +312,14 @@ class InternalTests(unittest.TestCase):
         self.assertEqual(searchfunc('1.2.3'), '1.2.3')
         self.assertEqual(searchfunc('foobar 2016.10.28 1.2.3'), '1.2.3')
         self.assertEqual(searchfunc('2016.10.28 1.2.3'), '1.2.3')
-        self.assertEqual(searchfunc('foobar 2016.10.128'), 'unknown version')
-        self.assertEqual(searchfunc('2016.10.128'), 'unknown version')
+        self.assertEqual(searchfunc('foobar 2016.10.128'), '2016.10.128')
+        self.assertEqual(searchfunc('2016.10.128'), '2016.10.128')
+        self.assertEqual(searchfunc('2016.10'), '2016.10')
+        self.assertEqual(searchfunc('2016.10 1.2.3'), '1.2.3')
+        self.assertEqual(searchfunc('oops v1.2.3'), '1.2.3')
+        self.assertEqual(searchfunc('2016.oops 1.2.3'), '1.2.3')
+        self.assertEqual(searchfunc('2016.x'), 'unknown version')
+
 
     def test_mode_symbolic_to_bits(self):
         modefunc = mesonbuild.mesonlib.FileMode.perms_s_to_bits
@@ -7768,7 +7774,7 @@ class CrossFileTests(BasePlatformTests):
     """
 
     def _cross_file_generator(self, *, needs_exe_wrapper: bool = False,
-                              exe_wrapper: typing.Optional[typing.List[str]] = None) -> str:
+                              exe_wrapper: T.Optional[T.List[str]] = None) -> str:
         if is_windows():
             raise unittest.SkipTest('Cannot run this test on non-mingw/non-cygwin windows')
         if is_sunos():