# `mix quality.plt`
[🔗](https://github.com/riddler/ex_quality/blob/v0.15.0/lib/mix/tasks/quality/plt.ex#L1)

Builds the Dialyzer PLT ahead of a `mix quality` run.

Dialyzer analyses against a PLT, a cache of every module it has already seen.
Building one takes minutes; analysing against a warm one takes seconds. With
no warm-up target, the first run on a cold checkout or a fresh CI container
pays that cost inside a check whose only output is one line at the end, so
the run looks hung.

This task is that target. It is the same work `mix quality` would otherwise
do, moved somewhere it can be cached:

    mix quality.plt

In a container image or a CI job, run it in its own step, after
`mix deps.get` and before any check, and cache `_build` and `~/.mix`
(dialyxir keeps the core PLTs in the Mix home directory and the project's
own under `_build`). The step is slow once and instant afterwards.

Output is not summarised: unlike a check, the whole point of this task is the
progress, so dialyxir's own output is passed through as it arrives.

Requires `:dialyxir`. A project without it has no PLT to build.

# `run`

```elixir
@spec run([String.t()]) :: :ok
```

Runs the PLT build.

Fails the task if dialyxir is not installed, or if the build itself failed.

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*Consult [api-reference.md](api-reference.md) for complete listing*