| <div align="center"> |
| <img src="https://github.com/mitsuhiko/insta/blob/master/assets/logo.png?raw=true" width="250" height="250"> |
| <p><strong>insta: a snapshot testing library for Rust</strong></p> |
| </div> |
| |
| [](https://github.com/mitsuhiko/insta/actions?query=workflow%3ATests) |
| [](https://crates.io/crates/insta) |
| [](https://github.com/mitsuhiko/insta/blob/master/LICENSE) |
| [](https://img.shields.io/badge/rust-1.46%2B-orange.svg) |
| [](https://docs.rs/insta) |
| [](https://marketplace.visualstudio.com/items?itemName=mitsuhiko.insta) |
| |
| ## Introduction |
| |
| Snapshots tests (also sometimes called approval tests) are tests that |
| assert values against a reference value (the snapshot). This is similar |
| to how `assert_eq!` lets you compare a value against a reference value but |
| unlike simple string assertions, snapshot tests let you test against complex |
| values and come with comprehensive tools to review changes. |
| |
| Snapshot tests are particularly useful if your reference values are very |
| large or change often. |
| |
| ## Example |
| |
| ```rust |
| #[test] |
| fn test_hello_world() { |
| insta::assert_debug_snapshot!(vec![1, 2, 3]); |
| } |
| ``` |
| |
| Curious? There is a screencast that shows the entire workflow: [watch the insta |
| introduction screencast](https://www.youtube.com/watch?v=rCHrMqE4JOY&feature=youtu.be). |
| Or if you're not into videos, read the [5 minute introduction](https://insta.rs/docs/quickstart/). |
| |
| Insta also supports inline snapshots which are stored right in your source file |
| instead of separate files. This is accomplished by the companion |
| [cargo-insta](https://crates.io/crates/cargo-insta) tool. |
| |
| ## Editor Support |
| |
| For looking at `.snap` files there is a [vscode extension](https://github.com/mitsuhiko/insta/tree/master/vscode-insta) |
| which can syntax highlight snapshot files, review snapshots and more. It can be installed from the |
| marketplace: [view on marketplace](https://marketplace.visualstudio.com/items?itemName=mitsuhiko.insta). |
| |
|  |
| |
| ## Diffing |
| |
| Insta uses [`similar`](https://github.com/mitsuhiko/similar) for all its diffing |
| operations. You can use it independently of insta. |
| |
| ## Sponsor |
| |
| If you like the project and find it useful you can [become a |
| sponsor](https://github.com/sponsors/mitsuhiko). |
| |
| ## License and Links |
| |
| - [Project Website](https://insta.rs/) |
| - [Documentation](https://docs.rs/insta/) |
| - [Issue Tracker](https://github.com/mitsuhiko/insta/issues) |
| - License: [Apache-2.0](https://github.com/mitsuhiko/insta/blob/master/LICENSE) |
