Replace Catch2's runner with the Catch3 runner

Catch3 keeps Catch2's API for writing tests (test cases, sections,
assertions, matchers, generators, listeners, benchmarks) and replaces its
session, command line and reporters with a runner of its own.

The runner starts the test binary again as worker processes that take the
next test when they are free. A crash, an exit or a hang ends one test, not
the run. On top of that it adds:

- retries that tell deterministic, flaky and order-dependent failures
  apart, and a bisection that names the test leaving state behind;
- a history of verdicts and durations, kept under a file lock, that drives
  automatic quarantine, adaptive time limits, predictive ordering,
  incremental runs, failure replay and analytics;
- selection by change, past failure or prediction, dependency closure,
  and sharding by a stable hash or by recorded durations;
- tags for serial and isolated tests, shared resources, dependencies,
  time limits and retries;
- a failure category, a signature, an analysis and a replay command for
  every failure;
- console, JUnit XML (with flakyFailure and rerunFailure), JSON and Chrome
  trace reports, and a versioned discovery listing (--list=json);
- a temporary directory per test (TMPDIR, TMP, TEMP and
  TestTemporaryDirectory());
- Bazel's test environment: XML output file, test filter, sharding, seed,
  premature exit file and undeclared outputs.

The command line is parsed by a hand-written, typed parser. Catch::Session
remains as a thin facade over the runner for custom main functions.

The result model in Progmasoft/Catch3/Results.hpp was rewritten around
tests and attempts, and the JUnit writer now writes it. The property
engine's example database is updated under a file lock with an atomic
rename, so parallel workers can write it at the same time.

Removed: Clara, the command-line and reporter-spec parsers, every reporter
and CATCH_REGISTER_REPORTER, listing, text flow, console colour and width,
the JSON and XML writers, sharding in the test registry, approval tests and
their baselines, Conan packaging, and the unused third_party/clara.hpp.
Listeners keep working; reporters' list and skip events are gone.

The Catch2 library is now compiled as C++20; code that includes only
Catch2's headers still needs C++14. Duplicate test cases are still refused
at start-up. Version 0.3.0.

ExtraTests now turn exceptions off for clang-cl with MSVC-style options,
which -fno-exceptions did not do.

1 files changed, 25 insertions, 41 deletions

diff --git a/tests/TestScripts/testBazelReporter.py b/tests/TestScripts/testBazelReporter.py
index 573eafd2..62600a39 100644
--- a/tests/TestScripts/testBazelReporter.py
+++ b/tests/TestScripts/testBazelReporter.py
@@ -14,12 +14,13 @@ import xml.etree.ElementTree as ET
 import subprocess
 
 """
-Test that Catch2 recognizes `XML_OUTPUT_FILE` env variable and creates
-a junit reporter that writes to the provided path.
+Test that the runner recognizes the `XML_OUTPUT_FILE` environment variable
+of Bazel and writes a JUnit report to the path it names.
 
-Requires 2 arguments, path to Catch2 binary configured with
-`CATCH_CONFIG_BAZEL_SUPPORT`, and the output directory for the output file.
+Requires 2 arguments, path to the test binary and the output directory for
+the report.
 """
+
 if len(sys.argv) != 3:
     print("Wrong number of arguments: {}".format(len(sys.argv)))
     print("Usage: {} test-bin-path output-dir".format(sys.argv[0]))
@@ -39,31 +40,21 @@ print('xml out path:', xml_out_path)
 
 env = os.environ.copy()
 env["XML_OUTPUT_FILE"] = xml_out_path
-test_passing = True
 
-try:
-    ret = subprocess.run(
-        bin_path,
-        stdout=subprocess.PIPE,
-        stderr=subprocess.PIPE,
-        check=True,
-        universal_newlines=True,
-        env=env
-    )
-    stdout = ret.stdout
-except subprocess.SubprocessError as ex:
-    if ex.returncode == 42:
-        # The test cases are allowed to fail.
-        test_passing = False
-        stdout = ex.stdout
-    else:
-        print('Could not run "{}"'.format(bin_path))
-        print("Return code: {}".format(ex.returncode))
-        print("stdout: {}".format(ex.stdout))
-        print("stderr: {}".format(ex.stderr))
-        raise
-
-# Check for valid XML output
+ret = subprocess.run(
+    [bin_path, '--retries=off'],
+    stdout=subprocess.PIPE,
+    stderr=subprocess.PIPE,
+    universal_newlines=True,
+    env=env
+)
+# One of the tests fails on purpose.
+if ret.returncode != 42:
+    print("Unexpected return code {}".format(ret.returncode))
+    print("stdout: {}".format(ret.stdout))
+    print("stderr: {}".format(ret.stderr))
+    exit(1)
+
 try:
     tree = ET.parse(xml_out_path)
 except ET.ParseError as ex:
@@ -73,24 +64,17 @@ except FileNotFoundError as ex:
     print("Could not find '{}'".format(xml_out_path))
     raise
 
-bin_name = os.path.basename(bin_path)
-# Check for matching testsuite
-if not tree.find('.//testsuite[@name="{}"]'.format(bin_name)):
+bin_name = os.path.splitext(os.path.basename(bin_path))[0]
+if tree.find('.//testsuite[@name="{}"]'.format(bin_name)) is None:
     print("Could not find '{}' testsuite".format(bin_name))
     exit(2)
 
-# Check that we haven't disabled the default reporter
-summary_test_cases = re.findall(r'test cases: \d* \| \d* passed \| \d* failed', stdout)
-if len(summary_test_cases) == 0:
-    print("Could not find test summary in {}".format(stdout))
-    exit(2)
-
-total, passed, failed = [int(s) for s in summary_test_cases[0].split() if s.isdigit()]
-
-if failed == 0 and not test_passing:
-    print("Expected at least 1 test failure!")
+summary = re.search(r'(\d+) test\(s\): (\d+) passed, (\d+) failed', ret.stdout)
+if summary is None:
+    print("Could not find test summary in {}".format(ret.stdout))
     exit(2)
 
+total, passed, failed = [int(value) for value in summary.groups()]
 if len(tree.findall('.//testcase')) != total:
     print("Unexpected number of test cases!")
     exit(2)