From 1014ee403f6bd65f55ec5e62a5d969dd6e286d3c Mon Sep 17 00:00:00 2001
From: "Ralf W. Grosse-Kunstleve" <rgrossekunst@nvidia.com>
Date: Sat, 20 Dec 2025 03:38:00 -0800
Subject: [PATCH] Add progress reporter for test_with_catch Catch2 runner

Add a custom Catch2 streaming reporter that prints one line per test
case as it starts and ends, with immediate flushing to keep CI logs
current. This makes it easy to see where the embedded/interpreter
tests are spending time and to pinpoint which test case is stuck
when builds hang (e.g., free-threading issues).

The reporter:
- Prints "[ RUN      ]" when each test starts
- Prints "[       OK ]" or "[  FAILED  ]" when each test ends
- Prints the Python version once at the start via Py_GetVersion()
- Uses StreamingReporterBase for immediate output (not buffered)
- Is set as the default reporter via CATCH_CONFIG_DEFAULT_REPORTER

This approach gives visibility into all tests without changing their
behavior, turning otherwise opaque 90-minute CI timeouts into
locatable issues in the Catch output.
---
 tests/test_with_catch/catch.cpp | 58 +++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/tests/test_with_catch/catch.cpp b/tests/test_with_catch/catch.cpp
index 5bd8b3880..5dbc01f67 100644
--- a/tests/test_with_catch/catch.cpp
+++ b/tests/test_with_catch/catch.cpp
@@ -13,10 +13,68 @@ PYBIND11_WARNING_DISABLE_MSVC(4996)
 #endif
 
 #define CATCH_CONFIG_RUNNER
+#define CATCH_CONFIG_DEFAULT_REPORTER "progress"
 #include <catch.hpp>
 
 namespace py = pybind11;
 
+// Simple progress reporter that prints a line per test case.
+namespace {
+
+class ProgressReporter : public Catch::StreamingReporterBase<ProgressReporter> {
+public:
+    using StreamingReporterBase<ProgressReporter>::StreamingReporterBase;
+
+    static std::string getDescription() { return "Simple progress reporter (one line per test)"; }
+
+    void testCaseStarting(Catch::TestCaseInfo const &testInfo) override {
+        print_python_version_once();
+        auto &os = Catch::cout();
+        os << "[ RUN      ] " << testInfo.name << '\n';
+        os.flush();
+    }
+
+    void testCaseEnded(Catch::TestCaseStats const &stats) override {
+        bool failed = stats.totals.assertions.failed > 0;
+        auto &os = Catch::cout();
+        os << (failed ? "[  FAILED  ] " : "[       OK ] ") << stats.testInfo.name << '\n';
+        os.flush();
+    }
+
+    void noMatchingTestCases(std::string const &spec) override {
+        auto &os = Catch::cout();
+        os << "[  NO TEST ] no matching test cases for spec: " << spec << '\n';
+        os.flush();
+    }
+
+    void reportInvalidArguments(std::string const &arg) override {
+        auto &os = Catch::cout();
+        os << "[   ERROR  ] invalid Catch2 arguments: " << arg << '\n';
+        os.flush();
+    }
+
+    void assertionStarting(Catch::AssertionInfo const &) override {}
+
+    bool assertionEnded(Catch::AssertionStats const &) override { return false; }
+
+private:
+    void print_python_version_once() {
+        if (printed_) {
+            return;
+        }
+        printed_ = true;
+        auto &os = Catch::cout();
+        os << "[ PYTHON   ] " << Py_GetVersion() << '\n';
+        os.flush();
+    }
+
+    bool printed_ = false;
+};
+
+} // namespace
+
+CATCH_REGISTER_REPORTER("progress", ProgressReporter)
+
 int main(int argc, char *argv[]) {
     // Setup for TEST_CASE in test_interpreter.cpp, tagging on a large random number:
     std::string updated_pythonpath("pybind11_test_with_catch_PYTHONPATH_2099743835476552");