r3bl_test_fixtures

Why R3BL?

R3BL TUI library & suite of apps focused on developer productivity

We are working on building command line apps in Rust which have rich text user interfaces (TUI). We want to lean into the terminal as a place of productivity, and build all kinds of awesome apps for it.

1. 🔮 Instead of just building one app, we are building a library to enable any kind of rich TUI development w/ a twist: taking concepts that work really well for the frontend mobile and web development world and re-imagining them for TUI & Rust.

   • Taking inspiration from things like React, SolidJS, Elm, iced-rs, Jetpack Compose, JSX, CSS, but making everything async (so they can be run in parallel & concurrent via Tokio).
   • Even the thread running the main event loop doesn't block since it is async.
   • Using proc macros to create DSLs to implement something inspired by CSS & JSX.

2. 🌎 We are building apps to enhance developer productivity & workflows.

   • The idea here is not to rebuild tmux in Rust (separate processes mux'd onto a single terminal window). Rather it is to build a set of integrated "apps" (or "tasks") that run in the same process that renders to one terminal window.
   • Inside of this terminal window, we can implement things like "app" switching, routing, tiling layout, stacking layout, etc. so that we can manage a lot of TUI apps (which are tightly integrated) that are running in the same process, in the same window. So you can imagine that all these "app"s have shared application state. Each "app" may also have its own local application state.
   • Here are some examples of the types of "app"s we plan to build (for which this infrastructure acts as the open source engine):
     1. Multi user text editors w/ syntax highlighting.
     2. Integrations w/ github issues.
     3. Integrations w/ calendar, email, contacts APIs.

All the crates in the r3bl-open-core repo provide lots of useful functionality to help you build TUI (text user interface) apps, along w/ general niceties & ergonomics that all Rustaceans 🦀 can enjoy 🎉.

Table of contents

• Introduction
• Changelog
• Learn how these crates are built, provide feedback
• async_stream_fixtures
• stdout_fixtures

Introduction

This is a test fixtures library that provides reusable components for testing. It is meant to be used by all the crates in the r3bl-open-core monorepo. This crate is intended to be a dev-dependency for other creates in the monorepo.

It provides fixtures to test async streams and stdout. This allows TUI frameworks to be tested "end to end".

1. The async stream fixtures are used to test the input stream of a TUI framework.
2. The stdout fixtures are used to test the output of a TUI framework.

Please check out the changelog to see how the library has evolved over time.

Changelog

Please check out the changelog to see how the library has evolved over time.

Learn how these crates are built, provide feedback

To learn how we built this crate, please take a look at the following resources.

• If you like consuming video content, here's our YT channel. Please consider subscribing.
• If you like consuming written content, here's our developer site. Please consider subscribing to our newsletter.
• If you have questions, please join our discord server.

async_stream_fixtures

Here's an example of how create a stream of T from a Vec<T>.

#[tokio::test]
async fn test_gen_input_stream() {
    use futures_util::StreamExt;
    use r3bl_test_fixtures::gen_input_stream;

    let mut input_stream = gen_input_stream(vec![1, 2, 3]);
    for _ in 1..=3 {
        input_stream.next().await;
    }
    pretty_assertions::assert_eq!(input_stream.next().await, None);
}

Here's another example of how to use this with a delay.

#[tokio::test]
async fn test_gen_input_stream_with_delay() {
    use futures_util::StreamExt;
    use r3bl_test_fixtures::gen_input_stream_with_delay;

    let delay = 100;

    // Start timer.
    let start_time = std::time::Instant::now();

    let mut input_stream = gen_input_stream_with_delay(vec![1, 2, 3], Duration::from_millis(delay));
    for _ in 1..=3 {
        input_stream.next().await;
    }

    // End timer.
    let end_time = std::time::Instant::now();

    pretty_assertions::assert_eq!(input_stream.next().await, None);

    assert!(end_time - start_time >= Duration::from_millis(delay * 3));
}

stdout_fixtures

Here's an example of how to use this.

#[tokio::test]
async fn test_stdout_mock_no_strip_ansi() {
    use strip_ansi_escapes::strip;

    use super::*;
    use std::{
        io::{Result, Write},
        sync::Arc,
    };

    let mut stdout_mock = StdoutMock::default();
    let stdout_mock_clone = stdout_mock.clone(); // Points to the same inner value as `stdout_mock`.

    let normal_text = "hello world";

    stdout_mock.write_all(normal_text.as_bytes()).unwrap();
    stdout_mock.flush().unwrap();

    pretty_assertions::assert_eq!(stdout_mock.get_copy_of_buffer_as_string(), normal_text);
    pretty_assertions::assert_eq!(
        stdout_mock_clone.get_copy_of_buffer_as_string(),
        normal_text
    );
}

License: Apache-2.0