Lit config attempt #<number>

Author: Sean Olszewski

Tests/Functional/lit.cfg

@@ -7,16 +7,18 @@
 #
 # See http://swift.org/LICENSE.txt for license information
 # See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
-
+from pkg_resources import parse_version
 import os
 import platform
 import tempfile
 import sys
 import lit
 import pipes
+import re
 
 # Set up lit config.
 config.name = 'SwiftXCTestFunctionalTests'
+config.os_info = (platform.system(), platform.mac_ver()[0])
 config.test_format = lit.formats.ShTest(execute_external=False)
 config.suffixes = ['.swift']
 
@@ -140,7 +142,9 @@ config.substitutions.append(('%{xctest_checker}', '%%{python} %s' % xctest_check
 # Add Python to run xctest_checker.py tests as part of XCTest tests
 config.substitutions.append( ('%{python}', pipes.quote(sys.executable)) )
 
-(run_cpu, run_vendor, run_os, run_vers) = re.match('([^-]+)-([^-]+)-([^0-9]+)(.*)', config.variant_triple).groups()
-
-if run_os != 'macosx' or run_vers >= 12:
+# Conditionally report the Swift 5.5 Concurrency runtime as available depending on the OS and version.
+(run_os, run_vers) = config.os_info
+os_is_not_macOS = run_os != 'Darwin'
+macOS_version_is_recent_enough = parse_version(run_vers) >= parse_version('12.0')
+if os_is_not_macOS or macOS_version_is_recent_enough:
     config.available_features.add('concurrency_runtime')