# `ExQuality.Aliases`
[🔗](https://github.com/riddler/ex_quality/blob/v0.15.0/lib/ex_quality/aliases.ex#L1)

Detects when a project's Mix aliases shadow a task a stage shells out to.

Mix resolves aliases before tasks, so `mix sobelow` in a project whose
`mix.exs` says

    aliases: [sobelow: ["cmd --app web mix sobelow --config"]]

runs the alias and ignores every switch a stage passed. The stage then
measures something other than what it asked for, and the failure is quiet:
a report that was never written, or a suite run twice and counted twice.

The task names ExQuality shells out to are exactly the ones projects most
like to alias - `credo`, `dialyzer`, `docs`, `format`, `sobelow`,
`deps.unlock`, `test.coverage` - so a stage whose parsing depends on its
exact invocation
asks here first, and refuses to run rather than reporting a number about a
command it did not issue.

Detection, not bypass: silently ignoring a project's alias is its own
surprise, and naming it gives the reader the choice.

## `test` is deliberately not on the list

A `test:` alias (`["ecto.create --quiet", "ecto.migrate", "test"]`) is
near-universal and running it is correct - it does the setup the suite needs.
`test.coverage` is different: it is pure aggregation, and an alias on it runs
the suite a second time before aggregating.

# `shadowed`

```elixir
@spec shadowed(String.t(), String.t()) :: ExQuality.Stage.result()
```

Returns an `:error` result for a stage that will not run because its task is
aliased, naming the alias and what to do about it.

The suggested rename is `<task>.all`, which is a name Mix will not resolve to
the real task and which reads as "the project's own wrapper".

    iex> result = ExQuality.Aliases.shadowed("Sobelow", "sobelow")
    iex> result.summary
    "mix sobelow is aliased in mix.exs"

# `shadowing?`

```elixir
@spec shadowing?(String.t() | atom()) :: boolean()
```

Returns true when the project defines a Mix alias with this task's name.

Safe to call outside a Mix project, where there are no aliases to shadow
anything.

    iex> ExQuality.Aliases.shadowing?("no.such.task")
    false

---

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