feat: add optional asynchronous/parallel support

[Daan Timmer (daantimmer)]

No description provided.

[github-actions]

✅⚠️MegaLinter analysis: Success with warnings

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
✅ ACTION	actionlint	6		0	0	0.03s
✅ CPP	clang-format	231	0	0	0	1.8s
✅ DOCKERFILE	hadolint	1		0	0	0.03s
⚠️ MARKDOWN	markdownlint	7	4	17	0	1.18s
✅ MARKDOWN	markdown-table-formatter	7	4	0	0	0.32s
✅ REPOSITORY	git_diff	yes		no	no	0.03s
✅ REPOSITORY	grype	yes		no	no	34.47s
✅ REPOSITORY	ls-lint	yes		no	no	0.1s
✅ REPOSITORY	secretlint	yes		no	no	4.57s
✅ REPOSITORY	syft	yes		no	no	2.18s
✅ REPOSITORY	trivy	yes		no	no	13.15s
✅ REPOSITORY	trivy-sbom	yes		no	no	0.27s
✅ REPOSITORY	trufflehog	yes		no	no	5.59s
⚠️ SPELL	lychee	86		1	0	3.43s
✅ YAML	prettier	10	0	0	0	0.75s
✅ YAML	v8r	10		0	0	9.0s
✅ YAML	yamllint	10		0	0	0.64s

Detailed Issues

⚠️ SPELL / lychee - 1 error

[404] https://github.com/yourname/amp-cucumber-cpp-runner.git | Network error: Not Found
📝 Summary
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🔍 Total..........159
✅ Successful.....158
⏳ Timeouts.........0
🔀 Redirected.......0
👻 Excluded.........0
❓ Unknown..........0
🚫 Errors...........1

Errors in CONTRIBUTING.md
[404] https://github.com/yourname/amp-cucumber-cpp-runner.git | Network error: Not Found

⚠️ MARKDOWN / markdownlint - 17 errors

CHANGELOG.md:30 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:37 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Chores"]
CHANGELOG.md:45 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "⚠ BREAKING CHANGES"]
CHANGELOG.md:49 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:58 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:64 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Chores"]
CHANGELOG.md:72 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "⚠ BREAKING CHANGES"]
CHANGELOG.md:76 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:81 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Bug Fixes"]
CHANGELOG.md:90 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:101 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Chores"]
CHANGELOG.md:109 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "⚠ BREAKING CHANGES"]
CHANGELOG.md:113 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Features"]
CHANGELOG.md:138 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Bug Fixes"]
CHANGELOG.md:145 error MD024/no-duplicate-heading Multiple headings with the same content [Context: "Chores"]
cmake/WindowsToolchainFilesProvidedBy.md:1 error MD041/first-line-heading/first-line-h1 First line in a file should be a top-level heading [Context: "<https://github.com/MarkSchofi..."]
README.md:114 error MD040/fenced-code-language Fenced code blocks should have a language specified [Context: "```"]

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Test Results

32 tests  +5   32 ✅ +5   34s ⏱️ +6s
 1 suites ±0    0 💤 ±0 
 1 files   ±0    0 ❌ ±0 

Results for commit a4987dc. ± Comparison against base commit 0811f80.

♻️ This comment has been updated with latest results.

[Copilot]

Pull request overview

Adds optional parallel scenario execution to the cucumber-cpp runner (guarded behind CCR_ENABLE_PARALLEL_SUPPORT / ENABLE_PARALLEL_SUPPORT) by introducing a libcoro-backed runtime adapter, along with supporting refactors to broadcasting and runtime wiring.

Changes:

• Add optional libcoro dependency plumbing and CMake presets for enabling parallel support.
• Refactor util::Broadcaster into an interface + BroadcasterImpl implementation to support parallelized event emission.
• Introduce ParallelRuntimeAdapter selected via new --parallel runtime option (when compiled with parallel support).

Reviewed changes

Copilot reviewed 27 out of 27 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
external/jbaldwin/libcoro/CMakeLists.txt	FetchContent integration for libcoro and warning suppression configuration.
external/jbaldwin/CMakeLists.txt	Adds jbaldwin subtree (libcoro) to the build.
external/CMakeLists.txt	Conditionally includes jbaldwin deps when CCR_ENABLE_PARALLEL_SUPPORT is on.
cucumber_cpp/library/util/Broadcaster.hpp	Converts broadcaster into an abstract interface; adds BroadcasterImpl.
cucumber_cpp/library/util/Broadcaster.cpp	Moves implementations onto BroadcasterImpl; minor const-correctness tweak.
cucumber_cpp/library/support/Types.hpp	Adds parallel option to runtime config; tweaks enum underlying type.
cucumber_cpp/library/runtime/Worker.hpp	Exposes hook/suite helpers needed by adapters; adds [[nodiscard]].
cucumber_cpp/library/runtime/Worker.cpp	Removes suite-level runner; small logic simplification and envelope construction tweaks.
cucumber_cpp/library/runtime/SerialRuntimeAdapter.hpp	Adds RunTestSuite(...) helper and includes for moved logic.
cucumber_cpp/library/runtime/SerialRuntimeAdapter.cpp	Hosts suite-level execution logic previously in Worker.
cucumber_cpp/library/runtime/ParallelRuntimeAdapter.hpp	New parallel runtime adapter interface (libcoro-based).
cucumber_cpp/library/runtime/ParallelRuntimeAdapter.cpp	New parallel execution implementation with thread pool + queued broadcasting.
cucumber_cpp/library/runtime/MakeRuntime.hpp	Removes exported MakeAdapter declaration (now internal).
cucumber_cpp/library/runtime/MakeRuntime.cpp	Selects serial vs parallel adapter based on options.parallel + build flag.
cucumber_cpp/library/runtime/CMakeLists.txt	Conditionally builds/links parallel adapter + libcoro; defines ENABLE_PARALLEL_SUPPORT.
cucumber_cpp/library/query/Query.hpp	Switches Query to inherit BroadcasterImpl (since Broadcaster is now abstract).
cucumber_cpp/library/formatter/helper/Theme.cpp	Removes unused optional helper.
cucumber_cpp/library/formatter/UsageFormatter.cpp	Avoids structured binding copies in loop.
cucumber_cpp/library/formatter/SummaryFormatter.cpp	Avoids structured binding copies; removes unused locals.
cucumber_cpp/library/engine/test/TestStep.cpp	Updates test fixture broadcaster type to BroadcasterImpl.
cucumber_cpp/library/Application.hpp	Adds parallel CLI option storage; updates broadcaster type + integer widths.
cucumber_cpp/library/Application.cpp	Registers --parallel when compiled with parallel support; plumbs into RunOptions.
compatibility/BaseCompatibility.cpp	Updates broadcaster type to BroadcasterImpl.
CMakePresets.json	Adds Host/Windows presets enabling parallel support.
CMakeLists.txt	Introduces CCR_ENABLE_PARALLEL_SUPPORT option; finds libcoro when enabled; standard settings moved earlier.
.vscode/launch.json	Updates debug args to include parallel run flags.
.clang-tidy	Disables coroutine reference-parameter guideline warning.

---

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[sonarqubecloud]

Quality Gate failed

Failed conditions
59.3% Coverage on New Code (required ≥ 80%)

See analysis details on SonarQube Cloud

[Xavier Bernhardt (XavierBernhardt-Philips)]

todo(?)

[Xavier Bernhardt (XavierBernhardt-Philips)]

ignore this daan

todo (me) read this function more

notes for me
i am uncertain about how the examples in the cg match up here https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#rcoro-capture
i think sonar has a point that its worth thinking about the lifetime of these params
is it better to have a unique pointer ref to tp here than a shared pointer or is that stupid to think about

[Xavier Bernhardt (XavierBernhardt-Philips)]

can the reference to latch being passed i become dangling or otherwise invalid between ShutdownTask's invocation and the line upon which its co_awaited on?

[heinwessels (heinwessels-philips)]

I'm not fully familiar with cucumber's nomenclature, like what does failing mean for a test, and what does dryrun mean.

But failing for this variable and function sounds wrong to me. In a dry-run the test can still fail right, the failure is just ignored? So should it not be called something like:

Suggested change

	failing |= IsFailing(util::GetWorstTestStepResult(synchronousWorker.RunBeforeAllHooks()).status, options.dryRun);
	runNextTest |= ShouldContinueTesting(util::GetWorstTestStepResult(synchronousWorker.RunBeforeAllHooks()).status, options.dryRun);