Support Bazel's TEST_PREMATURE_EXIT_FILE and add it to CLI as well

This tells Catch2 to create an empty file at specified path before
the tests start, and delete it after the tests finish. This allows
callers to catch cases where the test binary silently exits before
finishing (e.g. via call to `exit(0)` inside the code under test),
by looking whether the file still exists.

Closes #3020

1 files changed, 9 insertions, 0 deletions

diff --git a/src/catch2/catch_config.cpp b/src/catch2/catch_config.cpp
index 352c1f42..978bcfd7 100644
--- a/src/catch2/catch_config.cpp
+++ b/src/catch2/catch_config.cpp
@@ -119,6 +119,8 @@ namespace Catch {
             m_data.reporterSpecifications.push_back( std::move( *parsed ) );
         }
 
+        // Reading bazel env vars can change some parts of the config data,
+        // so we have to process the bazel env before acting on the config.
         if ( enableBazelEnvSupport() ) {
             readBazelEnvVars();
         }
@@ -183,6 +185,8 @@ namespace Catch {
 
     bool Config::showHelp() const { return m_data.showHelp; }
 
+    std::string const& Config::getExitGuardFilePath() const { return m_data.prematureExitGuardFilePath; }
+
     // IConfig interface
     bool Config::allowThrows() const                   { return !m_data.noThrow; }
     StringRef Config::name() const { return m_data.name.empty() ? m_data.processName : m_data.name; }
@@ -244,6 +248,11 @@ namespace Catch {
                 m_data.shardCount = bazelShardOptions->shardCount;
             }
         }
+
+        const auto bazelExitGuardFile = Detail::getEnv( "TEST_PREMATURE_EXIT_FILE" );
+        if (bazelExitGuardFile) {
+            m_data.prematureExitGuardFilePath = bazelExitGuardFile;
+        }
     }
 
 } // end namespace Catch