Soundcheck.Check.Warning.UndefinedStream (soundcheck v0.1.0)

Basics

This check has a base priority of high and works with any version of Elixir.

Explanation

Flags stream names a LiveView or LiveComponent uses but never defines. @streams holds only the streams that stream/4 or stream_async/4 created, so a template reading @streams.post when the module streams :posts raises KeyError on render, and stream_insert/4, stream_delete/3, or stream_delete_by_dom_id/3 on an unknown name raises ArgumentError.

Before:

def mount(_params, _session, socket),
  do: {:ok, stream(socket, :posts, Blog.list_posts())}

<div id="posts" phx-update="stream">
  <div :for={{id, post} <- @streams.post} id={id}>{post.title}</div>
</div>

After:

<div :for={{id, post} <- @streams.posts} id={id}>{post.title}</div>

Definitions are stream/3,4, stream_async/3,4, and stream_configure/3 calls with a literal atom name in the module's own functions and in the project functions it calls, through remote calls and imports at any depth. Reads come from its render/1 template, colocated or inline. The check skips a module when it and those functions define no stream, when any of them names one dynamically, or when it passes its socket to a function outside the project and Phoenix, since that function may define streams the check cannot see.

Confidence: medium. Tier: syntactic (works without compiling).

Check-Specific Parameters

Use the following parameters to configure this check:

:excluded_paths

Paths to skip (atoms, binaries as path segments, or regexes).

This parameter defaults to [~r/\/test\//, "test"].

:strict

Unused.

This parameter defaults to false.

General Parameters

Like with all checks, general params can be applied.

Parameters can be configured via the .credo.exs config file.