[build-script] Use more strict regex for --clang-compiler-version argument

Author: rintaro

utils/swift_build_support/swift_build_support/arguments.py

@@ -78,7 +78,7 @@ def type_clang_compiler_version(string):
 
     Support only "MAJOR.MINOR.PATCH" format.
     """
-    m = re.match(r'([0-9]*)\.([0-9]*)\.([0-9]*)', string)
+    m = re.match(r'^([0-9]+)\.([0-9]+)\.([0-9]+)$', string)
     if m is not None:
         return m.group(1, 2, 3)
     raise argparse.ArgumentTypeError(

utils/swift_build_support/tests/test_arguments.py

@@ -50,12 +50,18 @@ def test_clang_compiler_version(self):
             argparse.ArgumentTypeError,
             argtype.clang_compiler_version,
             "1.beta2.3")
-        self.assertEqual(
-            argtype.clang_compiler_version("1.2.preview3"),
-            ("1", "2", ""))
-        self.assertEqual(
-            argtype.clang_compiler_version("1.2.3-rc4"),
-            ("1", "2", "3"))
+        self.assertRaises(
+            argparse.ArgumentTypeError,
+            argtype.clang_compiler_version,
+            "1.2.preview3")
+        self.assertRaises(
+            argparse.ArgumentTypeError,
+            argtype.clang_compiler_version,
+            "1.2.3-rc4")
+        self.assertRaises(
+            argparse.ArgumentTypeError,
+            argtype.clang_compiler_version,
+            "1..2")
 
     def test_executable(self):
         python = sys.executable