test-pretty-log 0.5.0

test-pretty-log
========


**test-pretty-log** is a crate that takes care of automatically initializing
logging and/or tracing for Rust tests.
 
It is based off [test-log](https://github.com/d-e-s-o/test-log) and enables
the logs to use pretty colors! :3

Usage
-----

The crate provides a custom `#[test]` attribute that, when used for
running a particular test, takes care of initializing `log` and/or
`tracing` beforehand.

#### Example


As such, usage is as simple as importing and using said attribute:
```rust
use test_pretty_log::test;

#[test]

fn it_works() {
  info!("Checking whether it still works...");
  assert_eq!(2 + 2, 4);
  info!("Looks good!");
}
```

It is of course also possible to initialize logging for a chosen set of
tests, by only annotating these with the custom attribute:
```rust
#[test_pretty_log::test]

fn it_still_works() {
  // ...
}
```

You can also stack another attribute. For example, suppose you use
[`#[tokio::test]`][tokio-test] to run async tests:
```rust
use test_log::test;

#[test(tokio::test)]

async fn it_still_works() {
  // ...
}
```

Lastly, you can disable coloring for a test with a parameter:
```rust
use test_log::test;

#[test(color=false)]

fn no_more_colored_output() {
  // :blobfoxsad:
}
```

#### Logging Configuration


As usual when running `cargo test`, the output is captured by the
framework by default and only shown on test failure. The `--nocapture`
argument can be supplied in order to overwrite this setting. E.g.,
```bash
$ cargo test -- --nocapture
```

Furthermore, the `RUST_LOG` environment variable is honored and can be
used to influence the log level to work with (among other things).
Please refer to the [`env_logger` docs][env-docs-rs] for more
information.

If the `trace` feature is enabled, the `RUST_LOG_SPAN_EVENTS`
environment variable can be used to configure the tracing subscriber to
log synthesized events at points in the span lifecycle. Set the variable
to a comma-separated list of events you want to see. For example,
`RUST_LOG_SPAN_EVENTS=full` or `RUST_LOG_SPAN_EVENTS=new,close`.

Valid events are `new`, `enter`, `exit`, `close`, `active`, and `full`.
See the [`tracing_subscriber` docs][tracing-events-docs-rs] for details
on what the events mean.

The `RUST_LOG_COLOR` environment variable can be used to
configure outputting ANSI colors in the tracing subscriber to print
colorized logs. By default, this is enabled. Valid values are common
boolean representations (`f`, `false`, `off`, `0`, `t`, `true`, `on`, `1`).
The `color` parameter of the macro overrides this setting.

The `RUST_LOG_FORMAT` environment variable can be used to configure
the formatter of the tracing subcriber. By default, it is set to `pretty`.
Valid values are `pretty`, `full`, or `compact`.

#### Features


The crate comes with two features:
- `log`, enabled by default, controls initialization for the `log`
  crate.
- `trace`, disabled by default, controls initialization for the
  `tracing` crate.

Depending on what backend the crate-under-test (and its dependencies)
use, the respective feature should be enabled to make messages that are
emitted by the test manifest on the console.