snapshot

What

This is a CLI tool for text-based snapshot tests.

In the snapshot testing paradigm, a test case is an executable program which writes meaningful output to stdout. This output is recorded in a "snapshot" file and should be committed to version control alongside the test case. Later, if the test's output changes, the snapshot tool will report it as a failure.

Installation

$ go install github.com/aromatt/snapshot@latest

Usage

Usage: snapshot [flags] [test cases]
  -q    Suppress diff output
  -u    Update snapshots

The [test cases] argument can be files or directories.

The tool will look for executable files among the arguments you provide, and will execute all that have matching .snapshot files.

This repo has an example directory full of test cases:

$ tree example/
example/
├── fail.sh
├── fail.sh.snapshot
├── pass.sh
├── pass.sh.snapshot
├── python_pass.py
├── python_pass.py.snapshot
└── skip.sh

Output

The tool outputs a summary of the test run, including diffs for failed test cases (unless -q), and returns an exit code of 1 if any tests failed.

Example output:

$ snapshot example/
fail.sh               FAILED
1c1
< bar
---
> foo

pass.sh               PASSED
python_pass.py        PASSED
skip.sh               SKIPPED
1 failed, 2 passed, 1 skipped