md-cli-test

This is a helper library for integration testing of CLI applications in Rust using markdown files as a source of test cases.

Tester automatically extracts and runs command-line examples from code blocks in .md specification files, verifying the correctness of CLI application's output. It is especially useful when following a doctest-like approach for CLI examples, helping keep your documentation and tests in sync.

Features

Parses H1 headers from markdown file (# ) as test section titles
Parses code blocks from markdown file ( ```sh, ```shell) as test cases
Executes your CLI application and additional commands (cd, ls, mkdir, rm, echo, cat)
Verifies expected output lines
Supports Rust-style raw multi-line string arguments for commands

Example

Markdown file greeting.md:

# Greeting

```sh
$ my-cli greet Alice
Hello, Alice!
```

Test using this library:

use md_cli_test::Tester;

#[test]
fn greeting_test_cases() {
    Tester::new("tests/greeting.md").run().unwrap();
}

In more complex scenarios, you can also use aliase for binary, pass environment variables, and even use cd, ls, mkdir, rm, echo, cat commands.

For example, markdown file new_project.md for todo-cli application:

# New project

## New project default

```sh
$ todo new "project A"
    Creating `project A` project
```

```sh
$ ls "./project A"
Project.toml
```

```sh
$ cat "./project A/Project.toml"
id = "project A"
name = "project A"
```

```sh
$ todo new "project A"
    Creating `project A` project
Error: destination `${current_dir_path}/project A` already exists
```

Integration test file new_project.rs:

use md_cli_test::Tester;

#[test]
fn new_project_test_cases() {
    Tester::new("tests/new_project.md")
        // Use `todo` alias instead of real package or binary name
        .with_cargo_bin_alias("todo")
        // Alias must be matched to a real binary name `todo-cli`
        // if it does not match the package name
        .with_cargo_bin_name("todo-cli")
        // Pass environment variable
        .with_env("TODO_CONFIG", "./todo.toml")
        .run()
        .unwrap();
}

Usage

Add to your Cargo.toml:

[dev-dependencies]
md-cli-test = "0.1"

Why use this?

Keeps your documentation in sync with actual CLI behavior
Avoids duplication between examples and tests
Makes your documentation executable and verifiable

License