Merge pull request #4340 from mwichmann/test/runtest-pathlib

Use pathlib in runtest

21 files changed, 364 insertions, 294 deletions

diff --git a/CHANGES.txt b/CHANGES.txt
index d4ad973a0..5ad76b8de 100644
--- a/CHANGES.txt
+++ b/CHANGES.txt
@@ -23,6 +23,8 @@ RELEASE  VERSION/DATE TO BE FILLED IN LATER
       calls dunder method __call__. Invoke instance directly."
     - Python 3.9 dropped the alias base64.decodestring, deprecated since 3.1.
       Only used in msvs.py. Use base64.decodebytes instead.
+    - SCons test runner now uses pathlib to normalize and compare paths
+      to test files.
 
 
 RELEASE 4.5.2 -  Sun, 21 Mar 2023 14:08:29 -0700
diff --git a/RELEASE.txt b/RELEASE.txt
index c2244f27b..bafda4777 100644
--- a/RELEASE.txt
+++ b/RELEASE.txt
@@ -64,7 +64,11 @@ DOCUMENTATION
 DEVELOPMENT
 -----------
 
-- List visible changes in the way SCons is developed
+- SCons test runner now uses pathlib to normalize and compare paths
+  to test files, which allows test lists, exclude lists, and tests on
+  the command line to "not care" about the OS convention for pathname
+  separators.
+
 
 Thanks to the following contributors listed below for their contributions to this release.
 ==========================================================================================
diff --git a/runtest.py b/runtest.py
index a2ece7ee9..46cdc7b81 100755
--- a/runtest.py
+++ b/runtest.py
@@ -14,22 +14,17 @@ This script adds SCons/ and testing/ directories to PYTHONPATH,
 performs test discovery and processes tests according to options.
 """
 
-# TODO: normalize requested and testlist/exclude paths for easier comparison.
-# e.g.: "runtest foo/bar" on windows will produce paths like foo/bar\test.py
-# this is hard to match with excludelists, and makes those both os.sep-specific
-# and command-line-typing specific.
-
 import argparse
-import glob
+import itertools
 import os
-import stat
 import subprocess
 import sys
 import tempfile
 import threading
 import time
 from abc import ABC, abstractmethod
-from pathlib import Path
+from io import StringIO
+from pathlib import Path, PurePath, PureWindowsPath
 from queue import Queue
 
 cwd = os.getcwd()
@@ -39,7 +34,7 @@ scons = None
 catch_output = False
 suppress_output = False
 
-script = os.path.basename(sys.argv[0])
+script = PurePath(sys.argv[0]).name
 usagestr = """\
 %(script)s [OPTIONS] [TEST ...]
 """ % locals()
@@ -388,11 +383,13 @@ else:
 
 class RuntestBase(ABC):
     """ Base class for tests """
-    def __init__(self, path, num, spe=None):
-        self.path = path
-        self.num = num
+    _ids = itertools.count(1)  # to geenerate test # automatically
+
+    def __init__(self, path, spe=None):
+        self.path = str(path)
+        self.testno = next(self._ids)
         self.stdout = self.stderr = self.status = None
-        self.abspath = os.path.abspath(path)
+        self.abspath = path.absolute()
         self.command_args = []
         self.command_str = ""
         self.test_time = self.total_time = 0
@@ -404,7 +401,7 @@ class RuntestBase(ABC):
                     break
 
     @abstractmethod
-    def execute(self):
+    def execute(self, env):
         pass
 
 
@@ -547,7 +544,7 @@ if sys.platform == 'win32':
     # Windows doesn't support "shebang" lines directly (the Python launcher
     # and Windows Store version do, but you have to get them launched first)
     # so to directly launch a script we depend on an assoc for .py to work.
-    # Some systems may have none, and in some cases IDE programs take over 
+    # Some systems may have none, and in some cases IDE programs take over
     # the assoc.  Detect this so the small number of tests affected can skip.
     try:
         python_assoc = get_template_command('.py')
@@ -564,7 +561,7 @@ if '_JAVA_OPTIONS' in os.environ:
 
 
 # ---[ test discovery ]------------------------------------
-# This section figures which tests to run.
+# This section figures out which tests to run.
 #
 # The initial testlist is made by reading from the testlistfile,
 # if supplied, or by looking at the test arguments, if supplied,
@@ -587,10 +584,15 @@ if '_JAVA_OPTIONS' in os.environ:
 # Test exclusions, if specified, are then applied.
 
 
-def scanlist(testlist):
+def scanlist(testfile):
     """ Process a testlist file """
-    tests = [t.strip() for t in testlist if not t.startswith('#')]
-    return [t for t in tests if t]
+    data = StringIO(testfile.read_text())
+    tests = [t.strip() for t in data.readlines() if not t.startswith('#')]
+    # in order to allow scanned lists to work whether they use forward or
+    # backward slashes, first create the object as a PureWindowsPath which
+    # accepts either, then use that to make a Path object to use for
+    # comparisons like "file in scanned_list".
+    return [Path(PureWindowsPath(t)) for t in tests if t]
 
 
 def find_unit_tests(directory):
@@ -602,7 +604,8 @@ def find_unit_tests(directory):
             continue
         for fname in filenames:
             if fname.endswith("Tests.py"):
-                result.append(os.path.join(dirpath, fname))
+                result.append(Path(dirpath, fname))
+
     return sorted(result)
 
 
@@ -617,79 +620,74 @@ def find_e2e_tests(directory):
         # Slurp in any tests in exclude lists
         excludes = []
         if ".exclude_tests" in filenames:
-            p = Path(dirpath).joinpath(".exclude_tests")
-            # TODO simplify when Py3.5 dropped
-            if sys.version_info.major == 3 and sys.version_info.minor < 6:
-                excludefile = p.resolve()
-            else:
-                excludefile = p.resolve(strict=True)
-            with excludefile.open() as f:
-                excludes = scanlist(f)
+            excludefile = Path(dirpath, ".exclude_tests").resolve()
+            excludes = scanlist(excludefile)
 
         for fname in filenames:
-            if fname.endswith(".py") and fname not in excludes:
-                result.append(os.path.join(dirpath, fname))
+            if fname.endswith(".py") and Path(fname) not in excludes:
+                result.append(Path(dirpath, fname))
 
     return sorted(result)
 
 
 # initial selection:
+# if we have a testlist file read that, else hunt for tests.
 unittests = []
 endtests = []
 if args.testlistfile:
-    with args.testlistfile.open() as f:
-        tests = scanlist(f)
+    tests = scanlist(args.testlistfile)
 else:
     testpaths = []
-    if args.all:
-        testpaths = ['SCons', 'test']
-    elif args.testlist:
-        testpaths = args.testlist
-
-    for tp in testpaths:
-        # Clean up path so it can match startswith's below
-        # remove leading ./ or .\
-        if tp.startswith('.') and tp[1] in (os.sep, os.altsep):
-            tp = tp[2:]
-
-        for path in glob.glob(tp):
-            if os.path.isdir(path):
-                if path.startswith(('SCons', 'testing')):
+    if args.all:  # -a flag
+        testpaths = [Path('SCons'), Path('test')]
+    elif args.testlist:  # paths given on cmdline
+        testpaths = [Path(PureWindowsPath(t)) for t in args.testlist]
+
+    for path in testpaths:
+        # Clean up path removing leading ./ or .\
+        name = str(path)
+        if name.startswith('.') and name[1] in (os.sep, os.altsep):
+            path = path.with_name(tn[2:])
+
+        if path.exists():
+            if path.is_dir():
+                if path.parts[0] == "SCons" or path.parts[0] == "testing":
                     unittests.extend(find_unit_tests(path))
-                elif path.startswith('test'):
+                elif path.parts[0] == 'test':
                     endtests.extend(find_e2e_tests(path))
+                # else: TODO: what if user pointed to a dir outside scons tree?
             else:
-                if path.endswith("Tests.py"):
+                if path.match("*Tests.py"):
                     unittests.append(path)
-                elif path.endswith(".py"):
+                elif path.match("*.py"):
                     endtests.append(path)
-    tests = sorted(unittests + endtests)
 
+    tests = sorted(unittests + endtests)
 
 # Remove exclusions:
 if args.e2e_only:
-    tests = [t for t in tests if not t.endswith("Tests.py")]
+    tests = [t for t in tests if not t.match("*Tests.py")]
 if args.unit_only:
-    tests = [t for t in tests if t.endswith("Tests.py")]
+    tests = [t for t in tests if t.match("*Tests.py")]
 if args.excludelistfile:
-    with args.excludelistfile.open() as f:
-        excludetests = scanlist(f)
+    excludetests = scanlist(args.excludelistfile)
     tests = [t for t in tests if t not in excludetests]
 
+# did we end up with any tests?
 if not tests:
     sys.stderr.write(parser.format_usage() + """
-error: no tests were found.
-       Tests can be specified on the command line, read from a file with
-       the -f/--file option, or discovered with -a/--all to run all tests.
+error: no tests matching the specification were found.
+       See "Test selection options" in the help for details on
+       how to specify and/or exclude tests.
 """)
     sys.exit(1)
 
 # ---[ test processing ]-----------------------------------
-tests = [Test(t, n + 1) for n, t in enumerate(tests)]
+tests = [Test(t) for t in tests]
 
 if args.list_only:
     for t in tests:
-        sys.stdout.write(t.path + "\n")
+        print(t.path)
     sys.exit(0)
 
 if not args.python:
@@ -702,7 +700,7 @@ os.environ["python_executable"] = args.python
 if args.print_times:
 
     def print_time(fmt, tm):
-        sys.stdout.write(fmt % tm)
+        print(fmt % tm)
 
 else:
 
@@ -739,7 +737,7 @@ def log_result(t, io_lock=None):
                 print(t.stdout)
             if t.stderr:
                 print(t.stderr)
-        print_time("Test execution time: %.1f seconds\n", t.test_time)
+        print_time("Test execution time: %.1f seconds", t.test_time)
     finally:
         if io_lock:
             io_lock.release()
@@ -778,8 +776,8 @@ def run_test(t, io_lock=None, run_async=True):
     if args.printcommand:
         if args.print_progress:
             t.headline += "%d/%d (%.2f%s) %s\n" % (
-                t.num, total_num_tests,
-                float(t.num) * 100.0 / float(total_num_tests),
+                t.testno, total_num_tests,
+                float(t.testno) * 100.0 / float(total_num_tests),
                 "%",
                 t.command_str,
             )
@@ -843,7 +841,7 @@ else:
 # --- all tests are complete by the time we get here ---
 if tests:
     tests[0].total_time = time_func() - total_start_time
-    print_time("Total execution time for all tests: %.1f seconds\n", tests[0].total_time)
+    print_time("Total execution time for all tests: %.1f seconds", tests[0].total_time)
 
 passed = [t for t in tests if t.status == 0]
 fail = [t for t in tests if t.status == 1]
diff --git a/test/runtest/SCons.py b/test/runtest/SCons.py
index 20c4c6418..fc4c3e06c 100644
--- a/test/runtest/SCons.py
+++ b/test/runtest/SCons.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Verify that we find tests under the SCons/ tree only if they end
@@ -46,17 +45,17 @@ test.write_passing_test(['SCons', 'passTests.py'])
 test.write_passing_test(['SCons', 'suite', 'pass.py'])
 test.write_passing_test(['SCons', 'suite', 'passTests.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(src_passTests_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {src_passTests_py}
 PASSING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(src_suite_passTests_py)s
+{pythonstring}{pythonflags} {src_suite_passTests_py}
 PASSING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
 PASSING TEST STDERR
-""" % locals()
+"""
 
 test.run(arguments='-k SCons', stdout=expect_stdout, stderr=expect_stderr)
 
diff --git a/test/runtest/baseline/combined.py b/test/runtest/baseline/combined.py
index 228d42d1a..00ce85bdf 100644
--- a/test/runtest/baseline/combined.py
+++ b/test/runtest/baseline/combined.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a combination of a passing test, failing test, and no-result
@@ -42,27 +41,24 @@ test_pass_py = os.path.join('test', 'pass.py')
 test = TestRuntest.TestRuntest()
 
 test.subdir('test')
-
 test.write_failing_test(['test', 'fail.py'])
-
 test.write_no_result_test(['test', 'no_result.py'])
-
 test.write_passing_test(['test', 'pass.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_no_result_py)s
+{pythonstring}{pythonflags} {test_no_result_py}
 NO RESULT TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
 
 Failed the following test:
-\t%(test_fail_py)s
+\t{test_fail_py}
 
 NO RESULT from the following test:
-\t%(test_no_result_py)s
-""" % locals()
+\t{test_no_result_py}
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
@@ -70,10 +66,7 @@ NO RESULT TEST STDERR
 PASSING TEST STDERR
 """
 
-test.run(arguments='-k -b . test',
-         status=1,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(arguments='-k -b . test', status=1, stdout=expect_stdout, stderr=expect_stderr)
 
 test.pass_test()
 
diff --git a/test/runtest/baseline/fail.py b/test/runtest/baseline/fail.py
index e2aff4a22..2268dce84 100644
--- a/test/runtest/baseline/fail.py
+++ b/test/runtest/baseline/fail.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,38 +22,39 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test how we handle a failing test specified on the command line.
 """
 
+import os
+
 import TestRuntest
 
 pythonstring = TestRuntest.pythonstring
 pythonflags = TestRuntest.pythonflags
+test_fail_py = os.path.join('test', 'fail.py')
 
 test = TestRuntest.TestRuntest()
 
 test.subdir('test')
-
 test.write_failing_test(['test', 'fail.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s test/fail.py
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
 """
 
-test.run(arguments='-k -b . test/fail.py',
-         status=1,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='-k -b . test/fail.py',
+    status=1,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
 test.pass_test()
 
diff --git a/test/runtest/baseline/no_result.py b/test/runtest/baseline/no_result.py
index d00f5364f..ce6f20cbb 100644
--- a/test/runtest/baseline/no_result.py
+++ b/test/runtest/baseline/no_result.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,43 +22,45 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test how we handle a no-results test specified on the command line.
 """
 
+import os
+
 import TestRuntest
 
 pythonstring = TestRuntest.pythonstring
 pythonflags = TestRuntest.pythonflags
+test_no_result_py = os.path.join('test', 'no_result.py')
 
 test = TestRuntest.TestRuntest()
-
 test.subdir('test')
-
 test.write_no_result_test(['test', 'no_result.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s test/no_result.py
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_no_result_py}
 NO RESULT TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 NO RESULT TEST STDERR
 """
 
-test.run(arguments='--no-ignore-skips -k -b . test/no_result.py',
-         status=2,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='--no-ignore-skips -k -b . test/no_result.py',
+    status=2,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
-test.run(arguments='-k -b . test/no_result.py',
-         status=0,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='-k -b . test/no_result.py',
+    status=0,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
 
 test.pass_test()
diff --git a/test/runtest/baseline/pass.py b/test/runtest/baseline/pass.py
index 481fc9791..c31a6d6a8 100644
--- a/test/runtest/baseline/pass.py
+++ b/test/runtest/baseline/pass.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test how we handle a passing test specified on the command line.
@@ -42,18 +41,16 @@ test.subdir('test')
 
 test.write_passing_test(['test', 'pass.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
 """
 
-test.run(arguments='-k -b . test',
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(arguments='-k -b . test', stdout=expect_stdout, stderr=expect_stderr)
 
 test.pass_test()
 
diff --git a/test/runtest/faillog.py b/test/runtest/faillog.py
index e2ca67e63..f23b90bc7 100644
--- a/test/runtest/faillog.py
+++ b/test/runtest/faillog.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a list of tests in failed_tests.log to run with the --retry option
@@ -42,15 +41,15 @@ test.subdir('test')
 test.write_failing_test(test_fail_py)
 test.write_passing_test(test_pass_py)
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
 
 Failed the following test:
-\t%(test_fail_py)s
-""" % locals()
+\t{test_fail_py}
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
diff --git a/test/runtest/no_faillog.py b/test/runtest/no_faillog.py
index db17c8edf..174ab48c9 100644
--- a/test/runtest/no_faillog.py
+++ b/test/runtest/no_faillog.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a list of tests in failed_tests.log to run with the --retry option
@@ -42,19 +41,22 @@ test.subdir('test')
 test.write_failing_test(test_fail_py)
 test.write_passing_test(test_pass_py)
 
-test.write('failed_tests.log', """\
-%(test_fail_py)s
-""" % locals())
+test.write(
+    'failed_tests.log',
+    f"""\
+{test_fail_py}
+""",
+)
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
 
 Failed the following test:
-\t%(test_fail_py)s
-""" % locals()
+\t{test_fail_py}
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
diff --git a/test/runtest/pathseps.py b/test/runtest/pathseps.py
new file mode 100644
index 000000000..10d86b22e
--- /dev/null
+++ b/test/runtest/pathseps.py
@@ -0,0 +1,78 @@
+#!/usr/bin/env python
+#
+# MIT License
+#
+# Copyright The SCons Foundation
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+"""
+Make sure different path separators don't break things.
+Backslashes should be okay on POSIX, forwards slashes on win32,
+and combinations should cause no problems.
+"""
+
+import os.path
+
+import TestRuntest
+
+# the "expected" paths are generated os-native
+test_one_py = os.path.join('test', 'subdir', 'test1.py')
+test_two_py = os.path.join('test', 'subdir', 'test2.py')
+test_three_py = os.path.join('test', 'subdir', 'test3.py')
+test_four_py = os.path.join('test', 'subdir', 'test4.py')
+
+test = TestRuntest.TestRuntest()
+# create files for discovery
+testdir = "test/subdir".split("/")
+test.subdir(testdir[0], testdir)
+test.write_passing_test(testdir + ['test1.py'])
+test.write_passing_test(testdir + ['test2.py'])
+test.write_passing_test(testdir + ['test3.py'])
+test.write_passing_test(testdir + ['test4.py'])
+
+# discover tests using testlist file with various combinations of slashes
+test.write(
+    'testlist.txt',
+    r"""
+test/subdir/test1.py
+test\subdir/test2.py
+test/subdir\test3.py
+test\subdir\test4.py
+""",
+)
+
+# expect the discovered files to all be os-native
+expect_stdout = f"""\
+{test_one_py}
+{test_two_py}
+{test_three_py}
+{test_four_py}
+"""
+
+test.run(arguments="-k -l -f testlist.txt", stdout=expect_stdout, stderr=None)
+
+test.pass_test()
+
+# Local Variables:
+# tab-width:4
+# indent-tabs-mode:nil
+# End:
+# vim: set expandtab tabstop=4 shiftwidth=4:
diff --git a/test/runtest/print_time.py b/test/runtest/print_time.py
index 834d2ae45..3d49a9702 100644
--- a/test/runtest/print_time.py
+++ b/test/runtest/print_time.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a combination of a passing test, failing test, and no-result
@@ -41,30 +40,30 @@ test_fail_py = re.escape(os.path.join('test', 'fail.py'))
 test_no_result_py = re.escape(os.path.join('test', 'no_result.py'))
 test_pass_py = re.escape(os.path.join('test', 'pass.py'))
 
-test = TestRuntest.TestRuntest(match = TestCmd.match_re)
+test = TestRuntest.TestRuntest(match=TestCmd.match_re)
 test.subdir('test')
 test.write_failing_test(['test', 'fail.py'])
 test.write_no_result_test(['test', 'no_result.py'])
 test.write_passing_test(['test', 'pass.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
 Test execution time: \\d+.\\d seconds
-%(pythonstring)s%(pythonflags)s %(test_no_result_py)s
+{pythonstring}{pythonflags} {test_no_result_py}
 NO RESULT TEST STDOUT
 Test execution time: \\d+.\\d seconds
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
 Test execution time: \\d+.\\d seconds
 Total execution time for all tests: \\d+.\\d seconds
 
 Failed the following test:
-\t%(test_fail_py)s
+\t{test_fail_py}
 
 NO RESULT from the following test:
-\t%(test_no_result_py)s
-""" % locals()
+\t{test_no_result_py}
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
@@ -72,10 +71,7 @@ NO RESULT TEST STDERR
 PASSING TEST STDERR
 """
 
-test.run(arguments='-k -t test',
-         status=1,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(arguments='-k -t test', status=1, stdout=expect_stdout, stderr=expect_stderr)
 
 test.pass_test()
 
diff --git a/test/runtest/python.py b/test/runtest/python.py
index abd4f0cba..dbb24ca1a 100644
--- a/test/runtest/python.py
+++ b/test/runtest/python.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test that the -P option lets us specify a Python version to use.
@@ -46,26 +45,26 @@ head, dir = os.path.split(head)
 # python version then in use, which could be different
 pythonflags = TestRuntest.pythonflags
 
-# We have to normalize the python path here, because some installations don't like
-# getting called with "/bin/../bin/python" as first argument, e.g. Fedora 17 Desktop.
+# We have to normalize the python path here, because some installations
+# don't like getting called with "/bin/../bin/python" as first argument,
+# e.g. Fedora 17 Desktop.
 mypython = os.path.normpath(os.path.join(head, dir, os.path.pardir, dir, python))
 
 test.subdir('test')
-
 test.write_passing_test(['test', 'pass.py'])
 
-expect_stdout = """\
-%(mypython)s%(pythonflags)s %(test_pass_py)s
+expect_stdout = f"""\
+{mypython}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
 """
 
-test.run(arguments=['-k','-P', mypython, 'test'],
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments=['-k', '-P', mypython, 'test'], stdout=expect_stdout, stderr=expect_stderr
+)
 
 test.pass_test()
 
diff --git a/test/runtest/retry.py b/test/runtest/retry.py
index 4280152db..0c5beb694 100644
--- a/test/runtest/retry.py
+++ b/test/runtest/retry.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a list of tests in failed_tests.log to run with the --retry option
@@ -45,14 +44,17 @@ test.write_failing_test(['test', 'fail.py'])
 test.write_no_result_test(['test', 'no_result.py'])
 test.write_passing_test(['test', 'pass.py'])
 
-test.write('failed_tests.log', """\
-%(test_fail_py)s
-""" % locals())
+test.write(
+    'failed_tests.log',
+    f"""\
+{test_fail_py}
+""",
+)
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
diff --git a/test/runtest/simple/combined.py b/test/runtest/simple/combined.py
index a54e57c12..e594c5048 100644
--- a/test/runtest/simple/combined.py
+++ b/test/runtest/simple/combined.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a combination of a passing test, failing test, and no-result
@@ -45,20 +44,20 @@ test.write_failing_test(test_fail_py)
 test.write_no_result_test(test_no_result_py)
 test.write_passing_test(test_pass_py)
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_fail_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_no_result_py)s
+{pythonstring}{pythonflags} {test_no_result_py}
 NO RESULT TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
 
 Failed the following test:
-\t%(test_fail_py)s
+\t{test_fail_py}
 
 NO RESULT from the following test:
-\t%(test_no_result_py)s
-""" % locals()
+\t{test_no_result_py}
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
@@ -66,12 +65,7 @@ NO RESULT TEST STDERR
 PASSING TEST STDERR
 """
 
-test.run(
-    arguments='-k test',
-    status=1,
-    stdout=expect_stdout,
-    stderr=expect_stderr
-)
+test.run(arguments='-k test', status=1, stdout=expect_stdout, stderr=expect_stderr)
 test.must_exist('failed_tests.log')
 test.must_contain('failed_tests.log', test_fail_py)
 
diff --git a/test/runtest/simple/fail.py b/test/runtest/simple/fail.py
index f26f00e9a..5e1979a1b 100644
--- a/test/runtest/simple/fail.py
+++ b/test/runtest/simple/fail.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,38 +22,35 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test how we handle a failing test specified on the command line.
 """
 
+import os
+
 import TestRuntest
 
 pythonstring = TestRuntest.pythonstring
 pythonflags = TestRuntest.pythonflags
+test_fail_py = os.path.join('test', 'fail.py')
 
 test = TestRuntest.TestRuntest()
-
 test.subdir('test')
-
 test.write_failing_test(['test', 'fail.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s test/fail.py
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_fail_py}
 FAILING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 FAILING TEST STDERR
 """
 
-test.run(arguments='-k test/fail.py',
-         status=1,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='-k test/fail.py', status=1, stdout=expect_stdout, stderr=expect_stderr
+)
 
 test.pass_test()
 
diff --git a/test/runtest/simple/no_result.py b/test/runtest/simple/no_result.py
index 33f28e4a9..beb82b01c 100644
--- a/test/runtest/simple/no_result.py
+++ b/test/runtest/simple/no_result.py
@@ -27,35 +27,40 @@
 Test how we handle a no-results test specified on the command line.
 """
 
+import os
+
 import TestRuntest
 
 pythonstring = TestRuntest.pythonstring
 pythonflags = TestRuntest.pythonflags
+test_no_result_py = os.path.join('test', 'no_result.py')
 
 test = TestRuntest.TestRuntest()
-
 test.subdir('test')
-
 test.write_no_result_test(['test', 'no_result.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s test/no_result.py
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_no_result_py}
 NO RESULT TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 NO RESULT TEST STDERR
 """
 
-test.run(arguments='--no-ignore-skips -k test/no_result.py',
-         status=2,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='--no-ignore-skips -k test/no_result.py',
+    status=2,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
-test.run(arguments='-k test/no_result.py',
-         status=0,
-         stdout=expect_stdout,
-         stderr=expect_stderr)
+test.run(
+    arguments='-k test/no_result.py',
+    status=0,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
 
 test.pass_test()
diff --git a/test/runtest/simple/pass.py b/test/runtest/simple/pass.py
index 7ceb9a054..408ef4c28 100644
--- a/test/runtest/simple/pass.py
+++ b/test/runtest/simple/pass.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,29 +22,27 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test how we handle a passing test specified on the command line.
 """
 
+import os
+
 import TestRuntest
 
 pythonstring = TestRuntest.pythonstring
 pythonflags = TestRuntest.pythonflags
+test_pass_py = os.path.join('test', 'pass.py')
 
 test = TestRuntest.TestRuntest()
-
 test.subdir('test')
-
 test.write_passing_test(['test', 'pass.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s test/pass.py
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
diff --git a/test/runtest/testargv.py b/test/runtest/testargv.py
index 22e57e83b..20dcdc848 100644
--- a/test/runtest/testargv.py
+++ b/test/runtest/testargv.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test subdir args for runtest.py, for example:
@@ -38,34 +37,35 @@ import TestRuntest
 test = TestRuntest.TestRuntest()
 test.subdir('test', ['test', 'subdir'])
 
-files = {}
-files['pythonstring'] = TestRuntest.pythonstring
-files['pythonflags'] = TestRuntest.pythonflags
+pythonstring = TestRuntest.pythonstring
+pythonflags = TestRuntest.pythonflags
 
-files['one'] = os.path.join('test/subdir', 'test_one.py')
-files['two'] = os.path.join('test/subdir', 'two.py')
-files['three'] = os.path.join('test', 'test_three.py')
+one = os.path.join('test', 'subdir', 'test_one.py')
+two = os.path.join('test', 'subdir', 'two.py')
+three = os.path.join('test', 'test_three.py')
 
-test.write_passing_test(files['one'])
-test.write_passing_test(files['two'])
-test.write_passing_test(files['three'])
+test.write_passing_test(['test', 'subdir', 'test_one.py'])
+test.write_passing_test(['test', 'subdir', 'two.py'])
+test.write_passing_test(['test', 'test_three.py'])
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(one)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {one}
 PASSING TEST STDOUT
-%(pythonstring)s%(pythonflags)s %(two)s
+{pythonstring}{pythonflags} {two}
 PASSING TEST STDOUT
-""" % files
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
 PASSING TEST STDERR
 """
 
-test.run(arguments = '--no-progress test/subdir',
-         status = 0,
-         stdout = expect_stdout,
-         stderr = expect_stderr)
+test.run(
+    arguments='--no-progress test/subdir',
+    status=0,
+    stdout=expect_stdout,
+    stderr=expect_stderr,
+)
 
 test.pass_test()
 
diff --git a/test/runtest/testlistfile.py b/test/runtest/testlistfile.py
index 5c956b8e3..e5d85b8dc 100644
--- a/test/runtest/testlistfile.py
+++ b/test/runtest/testlistfile.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test a list of tests to run in a file specified with the -f option.
@@ -46,15 +45,18 @@ test.write_failing_test(['test', 'fail.py'])
 test.write_no_result_test(['test', 'no_result.py'])
 test.write_passing_test(['test', 'pass.py'])
 
-test.write('t.txt', """\
-#%(test_fail_py)s
-%(test_pass_py)s
-""" % locals())
+test.write(
+    't.txt',
+    f"""\
+#{test_fail_py}
+{test_pass_py}
+""",
+)
 
-expect_stdout = """\
-%(pythonstring)s%(pythonflags)s %(test_pass_py)s
+expect_stdout = f"""\
+{pythonstring}{pythonflags} {test_pass_py}
 PASSING TEST STDOUT
-""" % locals()
+"""
 
 expect_stderr = """\
 PASSING TEST STDERR
diff --git a/test/runtest/xml/output.py b/test/runtest/xml/output.py
index cd20dbdf9..66ec6562b 100644
--- a/test/runtest/xml/output.py
+++ b/test/runtest/xml/output.py
@@ -1,6 +1,8 @@
 #!/usr/bin/env python
 #
-# __COPYRIGHT__
+# MIT License
+#
+# Copyright The SCons Foundation
 #
 # Permission is hereby granted, free of charge, to any person obtaining
 # a copy of this software and associated documentation files (the
@@ -20,9 +22,6 @@
 # LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 # OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 # WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-#
-
-__revision__ = "__FILE__ __REVISION__ __DATE__ __DEVELOPER__"
 
 """
 Test writing XML output to a file.
@@ -34,8 +33,7 @@ import re
 import TestCmd
 import TestRuntest
 
-test = TestRuntest.TestRuntest(match = TestCmd.match_re,
-                               diff = TestCmd.diff_re)
+test = TestRuntest.TestRuntest(match=TestCmd.match_re, diff=TestCmd.diff_re)
 
 pythonstring = re.escape(TestRuntest.pythonstring)
 pythonflags = TestRuntest.pythonflags
@@ -44,22 +42,18 @@ test_no_result_py = re.escape(os.path.join('test', 'no_result.py'))
 test_pass_py = re.escape(os.path.join('test', 'pass.py'))
 
 test.subdir('test')
-
 test.write_fake_scons_source_tree()
-
 test.write_failing_test(['test', 'fail.py'])
-
 test.write_no_result_test(['test', 'no_result.py'])
-
 test.write_passing_test(['test', 'pass.py'])
 
-test.run(arguments = '--xml xml.out test', status=1)
+test.run(arguments='--xml xml.out test', status=1)
 
-expect = """\
+expect = f"""\
   <results>
     <test>
-      <file_name>%(test_fail_py)s</file_name>
-      <command_line>%(pythonstring)s%(pythonflags)s %(test_fail_py)s</command_line>
+      <file_name>{test_fail_py}</file_name>
+      <command_line>{pythonstring}{pythonflags} {test_fail_py}</command_line>
       <exit_status>1</exit_status>
       <stdout>FAILING TEST STDOUT
 </stdout>
@@ -68,8 +62,8 @@ expect = """\
       <time>\\d+\\.\\d</time>
     </test>
     <test>
-      <file_name>%(test_no_result_py)s</file_name>
-      <command_line>%(pythonstring)s%(pythonflags)s %(test_no_result_py)s</command_line>
+      <file_name>{test_no_result_py}</file_name>
+      <command_line>{pythonstring}{pythonflags} {test_no_result_py}</command_line>
       <exit_status>2</exit_status>
       <stdout>NO RESULT TEST STDOUT
 </stdout>
@@ -78,8 +72,8 @@ expect = """\
       <time>\\d+\\.\\d</time>
     </test>
     <test>
-      <file_name>%(test_pass_py)s</file_name>
-      <command_line>%(pythonstring)s%(pythonflags)s %(test_pass_py)s</command_line>
+      <file_name>{test_pass_py}</file_name>
+      <command_line>{pythonstring}{pythonflags} {test_pass_py}</command_line>
       <exit_status>0</exit_status>
       <stdout>PASSING TEST STDOUT
 </stdout>
@@ -89,7 +83,7 @@ expect = """\
     </test>
   <time>\\d+\\.\\d</time>
   </results>
-""" % locals()
+"""
 
 # Just strip carriage returns so the regular expression matching works.
 contents = test.read('xml.out')