#coverage #reporting #llvm-cov

app llvm-cov-pretty

More beautiful HTML reports for llvm-cov/cargo-llvm-cov

9 releases

0.1.9 Oct 10, 2023
0.1.8 Oct 6, 2023
0.1.7 Sep 25, 2023
0.1.6 Aug 23, 2023
0.1.3 Jun 23, 2023

#58 in Testing

Download history 4/week @ 2023-08-12 49/week @ 2023-08-19 8/week @ 2023-08-26 2/week @ 2023-09-02 17/week @ 2023-09-09 9/week @ 2023-09-16 34/week @ 2023-09-23 32/week @ 2023-09-30 31/week @ 2023-10-07 8/week @ 2023-10-14 12/week @ 2023-10-21 9/week @ 2023-10-28 1/week @ 2023-11-04 4/week @ 2023-11-11 19/week @ 2023-11-18 28/week @ 2023-11-25

52 downloads per month


1.5K SLoC

💄 llvm-cov-pretty

More beautiful HTML reports for llvm-cov (cargo-llvm-cov specifically).

  • Dark theme support (switches automatically based on your browser setting).
  • Syntax highlighting.
  • Reduced clutter from instantiation annotations.\
  • More colors, because why not.
  • Progress bars (like in grcov).

A note on stability

This tool is still in its early stages, and the JSON output of llvm-cov has several quirks and complexities. Therefore, for the time being, always generate the regular HTML report as well and compare the output.

Please file an issue if you find any differences.


Make sure you have cargo-llvm-cov installed.

From source

To build the project from source, you need a recent installation of Rust. The recommended installation method is through rustup. Then open up a terminal and install the project as follows:

cargo install llvm-cov-pretty

The binary will be installed into your $HOME/.cargo/bin folder by default. Please make sure it is available from your $PATH.

From AUR

Arch linux users can use an AUR helper to install the project from the AUR. For example, using paru:

paru -S llvm-cov-pretty

Pre-build binaries

If you don't want to build the project yourself, you can download pre-build binaries instead. Have a look at the release page and find the appropriate file for your platform.


Before you can use this tool, make sure the following steps are done:

  • In addition to installing cargo-llvm-cov, make sure you've run it at least once on your machine in any Rust project. It will jump into interactive mode and install any missing tools that it needs itself.
  • It is expected that you are in the context of a Rust project. Ensure you invoke the program while located in a Rust project in your terminal.
    • However, you can pass the --manifest-path argument, but make sure you pass the same path to both cargo-llvm-cov and llvm-cov-pretty.


The tool operates on the JSON output from llvm-cov. As cargo-llvm-cov directly prints those to the standard output, you can pipe the programs together like so:

cargo llvm-cov --json | llvm-cov-pretty

Of course you can do this in two steps as well:

cargo llvm-cov --json > coverage.json
llvm-cov-pretty coverage.json

There are a few extra commands (like generating shell completions) and options (like disabling instantiation annotations) as well. Have a look at the output of llvm-cov-pretty --help.


To start developing on the project, you'll need a few extra step in addition to the ones described in the From source section.

  • Install a recent version of Node.js and PNPM.
  • Ensure all submodules are initialized with git submodule update --init.

Then open up a new terminal and execute pnpm run watch. It will watch the project files and rebuild the stylesheet at assets/style.css when needed. With that you're ready to hack along.

Before you create a custom build, it's recommended to stop the watch job again and run pnpm run build once, which will create a minified and optimized version of the stylesheet. It is compiled into the binary during builds.


This project is licensed under the AGPL-3.0 License (or https://www.gnu.org/licenses/agpl-3.0.html).


~420K SLoC