/
unnecessary_alias_expansion.ex
48 lines (35 loc) · 1.24 KB
/
unnecessary_alias_expansion.ex
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defmodule Credo.Check.Readability.UnnecessaryAliasExpansion do
@moduledoc false
@checkdoc """
Alias expansion is useful but when aliasing a single module,
it can be harder to read with unnecessary braces.
# preferred
alias ModuleA.Foo
alias ModuleA.{Foo, Bar}
# NOT preferred
alias ModuleA.{Foo}
Like all `Readability` issues, this one is not a technical concern.
But you can improve the odds of others reading and liking your code by making
it easier to follow.
"""
@explanation [check: @checkdoc]
use Credo.Check, base_priority: :low
alias Credo.Code
@doc false
def run(source_file, params \\ []) do
issue_meta = IssueMeta.for(source_file, params)
Code.prewalk(source_file, &traverse(&1, &2, issue_meta))
end
defp traverse({:alias, _, [{_, _, [{:__aliases__, opts, [child]}]}]} = ast, issues, issue_meta) do
{ast, issues ++ [issue_for(issue_meta, Keyword.get(opts, :line), child)]}
end
defp traverse(ast, issues, _issue_meta), do: {ast, issues}
defp issue_for(issue_meta, line_no, trigger) do
format_issue(
issue_meta,
message: "Unnecessary alias expansion for #{trigger}, consider removing braces.",
trigger: trigger,
line_no: line_no
)
end
end