specdiff

Show how the test outline of a project has changed on a branch. If you're good about TDD, this tells you what the app code does. If you or or team are struggling to use tests, this tells you quickly what's missing or could be better described.

Features

RSpec, Minitest, pytest, Jest/Vitest/Mocha, Go testing, Rust #[test], ExUnit. Let me know if you'd like another language/framework supported.
Git and Jujutsu support with automatic backend detection
Tree-sitter parsing for syntax-aware test discovery
Shared example resolution (RSpec shared_examples, pytest conftest)
Rename detection with similarity scoring
Parameterized test awareness (rstest, pytest.mark.parametrize, Jest .each)
Output formats: colored tree (default), JSON, compact
TUI mode (default), --print

Requirements

Git: Any reasonably modern git (1.7+)
Jujutsu (optional): If a .jj directory is present, specdiff uses jj automatically

Installation

Homebrew (macOS/Linux)

brew tap michaeldhopkins/tap
brew install specdiff

From source

cargo install --git https://github.com/michaeldhopkins/specdiff

Manual download

Download binaries from GitHub Releases.

Usage

specdiff

Run in a git/jj repository. Opens a TUI that shows test outline changes on the current branch and live-refreshes when test files change.

Keybindings: q quit, c toggle changed-only, j/k scroll, PgUp/PgDn page scroll.

Non-interactive output

specdiff --print
specdiff -p --format json
specdiff -p --format compact

Options

Flag	Description
`-p`, `--print`	Print diff to stdout and exit (non-interactive)
`--base <REV>`	Base revision (default: auto-detected)
`--head <REV>`	Head revision (default: working copy)
`--format <FORMAT>`	Output format: `tree` (default), `json`, `compact`
`--changed-only`	Only show changed specs
`--framework <NAME>`	Force a specific framework
`--filter <PATTERN>`	Filter specs by name pattern
`--no-color`	Disable colored output
`-h`, `--help`	Print help
`-V`, `--version`	Print version

Example output

models::User
+   validates uniqueness of username
    validates email format
->  requires password -> validates password length
~   associations
+     has many comments
      has many posts
+ requests::admin
+   DELETE /users/:id returns 403

Legend: + added, - removed, -> renamed, ~ modified (children changed)

Supported Frameworks

Framework	Language	Detection
RSpec	Ruby	DSL (`describe`/`it`/`context`)
Minitest	Ruby	Class names (`Test`) + method names (`test_`)
pytest	Python	Class names (`Test`) + function names (`test_`)
Jest / Vitest / Mocha	JavaScript/TypeScript	DSL (`describe`/`it`/`test`)
Go testing	Go	Function names (`Test*`) + `t.Run` subtests
Rust built-in	Rust	`#[test]` + `#[cfg(test)]` attributes
rstest	Rust	`#[rstest]` parameterized tests
proptest	Rust	`proptest!` macro
ExUnit	Elixir	DSL (`describe`/`test`)

Framework knowledge is defined in TOML data files under frameworks/. Adding a new framework requires only a new TOML file in most cases.

Contributing

Requires Rust 1.85+.

cargo build
cargo test
cargo clippy --all-targets -- -D warnings
cargo deny check licenses

License

Dual-licensed under MIT or Apache-2.0.

specdiff 0.16.5