Merge pull request #15 from Progmasoft/feature/catch3-runner

Replace Catch2's runner with the Catch3 runner

5 files changed, 88 insertions, 79 deletions

diff --git a/fuzzing/CMakeLists.txt b/fuzzing/CMakeLists.txt
index 8370fe39..d300a19d 100644
--- a/fuzzing/CMakeLists.txt
+++ b/fuzzing/CMakeLists.txt
@@ -7,14 +7,20 @@
 add_library(fuzzhelper NullOStream.h NullOStream.cpp)
 target_link_libraries(fuzzhelper PUBLIC Catch2::Catch2)
 
-# use C++17 so we can get string_view
-target_compile_features(fuzzhelper PUBLIC cxx_std_17)
+# The runner fuzzers include its C++20 headers.
+target_compile_features(fuzzhelper PUBLIC cxx_std_20)
 
 # This should be possible to set from the outside to be oss-fuzz compatible,
 # fix later. For now, target libFuzzer only.
 target_link_options(fuzzhelper PUBLIC "-fsanitize=fuzzer")
 
-foreach(fuzzer TestSpecParser XmlWriter textflow)
+foreach(fuzzer TestSpecParser)
   add_executable(fuzz_${fuzzer} fuzz_${fuzzer}.cpp)
   target_link_libraries(fuzz_${fuzzer} PRIVATE fuzzhelper)
 endforeach()
+
+# Progmasoft's fuzzers live apart, under their own license header.
+foreach(fuzzer RunnerJson RunnerOptions)
+  add_executable(fuzz_${fuzzer} Progmasoft/fuzz_${fuzzer}.cpp)
+  target_link_libraries(fuzz_${fuzzer} PRIVATE fuzzhelper)
+endforeach()
diff --git a/fuzzing/Progmasoft/fuzz_RunnerJson.cpp b/fuzzing/Progmasoft/fuzz_RunnerJson.cpp
new file mode 100644
index 00000000..4cc3770c
--- /dev/null
+++ b/fuzzing/Progmasoft/fuzz_RunnerJson.cpp
@@ -0,0 +1,29 @@
+// Copyright (c) 2026 Progmasoft.
+// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-1.1
+
+// The runner reads JSON from its workers, from history files and from
+// reports; none of them may crash it. A document that parses must also
+// print and parse back to the same text.
+
+#include <Progmasoft/Runner/Json.hpp>
+
+#include <cstdint>
+#include <cstdlib>
+#include <string_view>
+
+extern "C" int
+LLVMFuzzerTestOneInput(const std::uint8_t *data, std::size_t size)
+{
+    const std::string_view text{reinterpret_cast<const char *>(data), size};
+    auto parsed = Progmasoft::Catch3::Runner::ParseJson(text);
+    if (parsed)
+    {
+        const auto printed = parsed->ToString();
+        auto again = Progmasoft::Catch3::Runner::ParseJson(printed);
+        if (!again || again->ToString() != printed)
+        {
+            std::abort();
+        }
+    }
+    return 0;
+}
diff --git a/fuzzing/Progmasoft/fuzz_RunnerOptions.cpp b/fuzzing/Progmasoft/fuzz_RunnerOptions.cpp
new file mode 100644
index 00000000..2a10ba91
--- /dev/null
+++ b/fuzzing/Progmasoft/fuzz_RunnerOptions.cpp
@@ -0,0 +1,50 @@
+// Copyright (c) 2026 Progmasoft.
+// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-1.1
+
+// The command line of a test binary: arguments separated by NUL bytes. The
+// parser must answer with options or an error, never crash, and the worker
+// arguments it derives must parse again.
+
+#include <Progmasoft/Runner/Options.hpp>
+
+#include <cstdint>
+#include <cstdlib>
+#include <string>
+#include <vector>
+
+extern "C" int
+LLVMFuzzerTestOneInput(const std::uint8_t *data, std::size_t size)
+{
+    std::vector<std::string> arguments(1);
+    for (std::size_t index = 0; index < size; ++index)
+    {
+        if (data[index] == 0)
+        {
+            arguments.emplace_back();
+        }
+        else
+        {
+            arguments.back().push_back(static_cast<char>(data[index]));
+        }
+    }
+    // Reading a file named by --input-file is not what is fuzzed here.
+    for (const auto &argument : arguments)
+    {
+        if (argument.find("input-file") != std::string::npos ||
+            (argument.size() >= 2 && argument[0] == '-' && argument[1] == 'f'))
+        {
+            return 0;
+        }
+    }
+    auto options = Progmasoft::Catch3::Runner::ParseOptions(arguments);
+    if (options)
+    {
+        const auto worker = Progmasoft::Catch3::Runner::ParseOptions(
+            Progmasoft::Catch3::Runner::WorkerArguments(*options));
+        if (!worker)
+        {
+            std::abort();
+        }
+    }
+    return 0;
+}
diff --git a/fuzzing/fuzz_XmlWriter.cpp b/fuzzing/fuzz_XmlWriter.cpp
deleted file mode 100644
index 70c4ed80..00000000
--- a/fuzzing/fuzz_XmlWriter.cpp
+++ /dev/null
@@ -1,22 +0,0 @@
-
-//              Copyright Catch2 Authors
-// Distributed under the Boost Software License, Version 1.0.
-//   (See accompanying file LICENSE.txt or copy at
-//        https://www.boost.org/LICENSE_1_0.txt)
-
-// SPDX-License-Identifier: BSL-1.0
-//By Paul Dreik 2020
-
-#include <catch2/internal/catch_xmlwriter.hpp>
-
-#include "NullOStream.h"
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
-
-    std::string buf(Data,Data+Size);
-    NullOStream nul;
-    Catch::XmlEncode encode(buf);
-    encode.encodeTo(nul);
-    return 0;
-}
-
diff --git a/fuzzing/fuzz_textflow.cpp b/fuzzing/fuzz_textflow.cpp
deleted file mode 100644
index f3119379..00000000
--- a/fuzzing/fuzz_textflow.cpp
+++ /dev/null
@@ -1,54 +0,0 @@
-
-//              Copyright Catch2 Authors
-// Distributed under the Boost Software License, Version 1.0.
-//   (See accompanying file LICENSE.txt or copy at
-//        https://www.boost.org/LICENSE_1_0.txt)
-
-// SPDX-License-Identifier: BSL-1.0
-//By Paul Dreik 2020
-
-#include <catch2/internal/catch_textflow.hpp>
-
-#include "NullOStream.h"
-
-#include <string>
-#include <string_view>
-#include <cstdint>
-
-
-template<class Callback>
-void split(const char *Data, size_t Size, Callback callback) {
-
-    using namespace std::literals;
-    constexpr auto sep="\n~~~\n"sv;
-
-    std::string_view remainder(Data,Size);
-    for (;;) {
-        auto pos=remainder.find(sep);
-        if(pos==std::string_view::npos) {
-            //not found. use the remainder and exit
-            callback(remainder);
-            return;
-        } else {
-            //found. invoke callback on the first part, then proceed with the rest.
-            callback(remainder.substr(0,pos));
-            remainder=remainder.substr(pos+sep.size());
-        }
-    }
-}
-
-extern "C" int LLVMFuzzerTestOneInput(const uint8_t *Data, size_t Size) {
-
-    Catch::TextFlow::Columns columns;
-
-    // break the input on separator
-    split((const char*)Data,Size,[&](std::string_view word) {
-        columns+=Catch::TextFlow::Column(std::string(word));
-    });
-
-    NullOStream nul;
-    nul << columns;
-
-    return 0;
-}
-