swift-custom-dump
swift-custom-dump is a Swift debugging and testing utility that provides improved output formatting for data structures compared to Swift's built-in dump function. It includes diff capabilities and assertion helpers for test writing.
Key facts
Objective fields from the source. Values we can't verify are shown as “Unknown” rather than guessed.
| Field | Value |
|---|---|
| Repository | pointfreeco/swift-custom-dump |
| Owner | pointfreeco |
| Primary language | Swift |
| License | MIT — OSI-approved |
| Stars | 882 |
| Forks | 110 |
| Open issues | 11 |
| Latest release | 1.6.1 (2026-06-19) |
| Last updated | 2026-07-03 |
| Source | https://github.com/pointfreeco/swift-custom-dump |
What swift-custom-dump is
A Swift Package Manager library offering customDump() for readable structure inspection, diff() for textual comparison, and expectNoDifference/expectDifference assertion helpers. Supports customization via CustomDumpStringConvertible, CustomDumpReflectable, and CustomDumpRepresentable protocols.
Get the swift-custom-dump source
Clone the repository and explore it locally.
git clone https://github.com/pointfreeco/swift-custom-dump.gitcd swift-custom-dump# follow the project's README for install & configurationNeed it deployed, integrated, or customized instead? DEV.co ships production installs.
Best use cases
Implementation considerations
- Integrate into test targets via SPM with `swift-custom-dump` dependency; no changes needed to production target code.
- Customize output for domain types by conforming to CustomDumpStringConvertible, CustomDumpReflectable, or CustomDumpRepresentable as needed.
- Replace existing XCTAssertEqual and #expect(_ == _) calls with expectNoDifference where detailed diff output aids test readability.
- Review expected behavior when comparing types with Objective-C imports; README notes limited output for some ObjC-bridged enums.
- Verify Swift version and platform compatibility via SwiftPackageIndex badges; ensure your minimum deployment target is supported.
When to avoid it — and what to weigh
- Non-Swift or Polyglot Environments — This is a Swift-only library; it provides no value in Objective-C, Java, Kotlin, or multi-language codebases.
- Production Runtime Performance Requirements — customDump and diff are reflection-heavy and suitable for debug/test code, not for performance-critical production paths.
- Snapshot Testing as Primary Need — If you need comprehensive snapshot testing infrastructure, consider dedicated tools like SnapshotTesting or Pointfree's own snapshot frameworks.
- CI/CD Binary Size Constraints — If binary bloat is a concern, verify the footprint added by this library and its reflection dependencies in your distribution.
License & commercial use
Licensed under the MIT License, which is a permissive OSI-approved license.
MIT License permits commercial use, modification, and distribution with attribution. No commercial restrictions or licensing fees apply. Verify your own legal review for compliance in commercial contexts.
DEV.co evaluation signals
Editorial assessment — not user reviews. Directional, with an explicit confidence level.
| Signal | Assessment |
|---|---|
| Maintenance | Active |
| Documentation | Strong |
| License clarity | Clear |
| Deployment complexity | Low |
| DEV.co fit | Good |
| Assessment confidence | High |
Security implications are minimal for test/debug-only usage. Reflection-based introspection does not expose sensitive data beyond what is already present in memory during testing. No network, file I/O, or external service integration. Ensure customDump output is not logged to production or public-facing surfaces.
Alternatives to consider
Swift's Built-in dump()
Free and always available, but produces verbose and hard-to-read output for nested structures and dictionaries; less suitable for test assertions.
Pointfree SnapshotTesting
Broader snapshot and regression testing framework; heavier-weight but supports file-based snapshots and multi-format comparisons if that is the primary need.
XCTest XCTAssertEqual with String Diffing (custom)
Manual diff implementation or third-party XCTest extensions; requires more boilerplate but avoids external dependency if minimalism is paramount.
Build on swift-custom-dump with DEV.co software developers
Add swift-custom-dump to your test suite today for clearer assertion failures and better debugging. Lightweight, MIT-licensed, and actively maintained.
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swift-custom-dump FAQ
Can I use custom-dump in production code?
Does it work with Equatable types?
How do I customize the dump output for my own types?
Is it compatible with Swift Testing and XCTest?
Work with a software development agency
DEV.co helps companies turn open-source tools like swift-custom-dump into production software. Our software development services cover the full lifecycle — architecture, web development, integration, and maintenance — delivered by software developers and web developers who ship. Engage our software development agency to implement or customize it for your open-source testing stack.
Ready to improve your Swift testing?
Add swift-custom-dump to your test suite today for clearer assertion failures and better debugging. Lightweight, MIT-licensed, and actively maintained.