Add default reporter for Bazel integration (#2399)

When the added Bazel configuration flag is enabled,
a default JUnit reporter will be added if the XML
envrioment variable is defined.
Fix include paths for generated config header.
Enable Bazel config by default when building with
Bazel.


Co-authored-by: Martin Hořeňovský <martin.horenovsky@gmail.com>

tests/ExtraTests/CMakeLists.txt

@@ -121,6 +121,14 @@ set_tests_properties(
     FAIL_REGULAR_EXPRESSION "abort;terminate;fatal"
 )
 
+add_executable( BazelReporter ${TESTS_DIR}/X30-BazelReporter.cpp )
+target_compile_definitions( BazelReporter PRIVATE CATCH_CONFIG_BAZEL_SUPPORT )
+target_link_libraries(BazelReporter Catch2_buildall_interface)
+add_test(NAME CATCH_CONFIG_BAZEL_REPORTER-1
+  COMMAND
+  "${PYTHON_EXECUTABLE}" "${CATCH_DIR}/tests/TestScripts/testBazelReporter.py" $<TARGET_FILE:BazelReporter> "${CMAKE_CURRENT_BINARY_DIR}"
+)
+
 
 # The default handler on Windows leads to the just-in-time debugger firing,
 # which makes this test unsuitable for CI and headless runs, as it opens

tests/ExtraTests/X30-BazelReporter.cpp

@@ -0,0 +1,17 @@
+
+//              Copyright Catch2 Authors
+// Distributed under the Boost Software License, Version 1.0.
+//   (See accompanying file LICENSE_1_0.txt or copy at
+//        https://www.boost.org/LICENSE_1_0.txt)
+
+// SPDX-License-Identifier: BSL-1.0
+
+/**\file
+ * Test the Bazel report functionality with a simple set
+ * of dummy test cases.
+ */
+
+#include <catch2/catch_test_macros.hpp>
+
+TEST_CASE( "Passing test case" ) { REQUIRE( 1 == 1 ); }
+TEST_CASE( "Failing test case" ) { REQUIRE( 2 == 1 ); }

tests/TestScripts/testBazelReporter.py

@@ -0,0 +1,104 @@
+#!/usr/bin/env python3
+
+#              Copyright Catch2 Authors
+# Distributed under the Boost Software License, Version 1.0.
+#   (See accompanying file LICENSE_1_0.txt or copy at
+#        https://www.boost.org/LICENSE_1_0.txt)
+
+# SPDX-License-Identifier: BSL-1.0
+
+import os
+import re
+import sys
+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.
+
+Requires 2 arguments, path to Catch2 binary configured with
+`CATCH_CONFIG_BAZEL_SUPPORT`, and the output directory for the output file.
+"""
+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]))
+    exit(1)
+
+
+bin_path = os.path.abspath(sys.argv[1])
+output_dir = os.path.abspath(sys.argv[2])
+xml_out_path = os.path.join(output_dir, "bazel-out.xml")
+
+# Ensure no file exists from previous test runs
+if os.path.isfile(xml_out_path):
+    os.remove(xml_out_path)
+
+print('bin path:', bin_path)
+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 == 1:
+        # The test cases are allowed to fail.
+        test_passing = False
+        stdout = ex.stdout
+    else:
+        print('Could not run "{}"'.format(args))
+        print("Return code: {}".format(ex.returncode))
+        print("stdout: {}".format(ex.stdout))
+        print("stderr: {}".format(ex.stdout))
+        raise
+
+# Check for valid XML output
+try:
+    tree = ET.parse(xml_out_path)
+except ET.ParseError as ex:
+    print("Invalid XML: '{}'".format(ex))
+    raise
+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)):
+    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!")
+    exit(2)
+
+if len(tree.findall('.//testcase')) != total:
+    print("Unexpected number of test cases!")
+    exit(2)
+
+if len(tree.findall('.//failure')) != failed:
+    print("Unexpected number of test failures!")
+    exit(2)
+
+if (passed + failed) != total:
+    print("Something has gone very wrong, ({} + {}) != {}".format(passed, failed, total))
+    exit(2)