This is an internalized and modernized copy of github.com/davecgh/go-spew, a deep pretty printer for Go data structures.

Source repository: github.com/davecgh/go-spew

Original license: ISC License (see LICENSE)

Copyright: 2012-2016 Dave Collins

go-spew implements a deep pretty printer for Go data structures to aid in debugging, providing features like pointer dereferencing, circular reference detection, custom Stringer/error interface handling, and hexdump-style byte array output.

This fork of testify maintains zero external dependencies for its core assertion packages. By internalizing go-spew, we eliminate the external dependency while gaining full control over the code to apply modernizations aligned with our go1.24 target.

This internalized copy has been modernized from the original go-spew codebase with the following changes:

• Type aliases: Replaced interface{} with any throughout
• Modern build tags: Updated from // +build to //go:build format
• Range iteration: Used for i := range n instead of for i := 0; i < n; i++
• reflect.TypeFor: Replaced reflect.TypeOf(T(0)) with reflect.TypeFor[T]()
• Standard library improvements: Used strings.ReplaceAll() instead of strings.Replace(..., -1)

• Linting compliance: Added linting directives (//nolint) with explanations where appropriate
• Test improvements: Added t.Helper() calls in test helper functions
• Modern idioms: Used slices.Contains() instead of manual loops
• String building: Used strings.Builder for efficient string concatenation
• Code organization: Improved struct field ordering and switch statement structure with explicit fallthrough comments

• Markdown formatting: Updated godoc documentation comments to use modern markdown headings (#) and list formats (-)
• Comment punctuation: Standardized comment punctuation and formatting
• Clarity improvements: Fixed typos and improved readability

• Test data relocation: Moved testdata/ to testsrc/ with proper documentation

The internalized copy maintains API compatibility with the original while incorporating targeted improvements:

• Deterministic map sorting: The SpewKeys configuration option enables sorted map key output for consistent diffs (relevant for testify's assertion output)
  • Additional optimizations for deterministic diff generation (stretchr/testify#1822)
• time.Time rendering: Enhanced handling of time.Time values in nested structures (applied from stretchr/testify#1829)
• panic/hang Reinforced input checking to avoid edge cases
  • Proper fix for panic on unexported struct keys in maps (stretchr/testify#1816)
  • Fix for circular map references (runtime stack overflow)

The linting effort is still going on...

This internalized copy is maintained as part of github.com/go-openapi/testify/v2 and follows the same Go version requirements (currently go1.24). It does not track upstream go-spew releases, as it has diverged through modernization.

For issues or improvements specific to this internalized version, please file issues at: https://github.com/go-openapi/testify/issues

This code retains its original ISC License. See LICENSE for the full license text.

The original copyright and license terms are preserved in accordance with the ISC License requirements.