Linter Rule: Disallow multiple Ruby statements in a single-line ERB tag

Rule: erb-no-multiple-statements

Description

Disallow multiple Ruby statements separated by semicolons within a single-line ERB tag. Each ERB tag on a single line should contain at most one Ruby statement.

Rationale

Multiple Ruby statements on a single line in an ERB tag reduce readability and make templates harder to maintain. Splitting statements into separate ERB tags makes each statement easier to understand at a glance.

This rule only applies to single-line ERB tags. Multi-line ERB tags are not checked, as they naturally provide visual separation between statements.

Examples

✅ Good

<% user = User.find(1) %>
<% post = user.posts.first %>

<%= user.name %>

<%
  user = User.find(1)
  post = user.posts.first
%>

🚫 Bad

<% user = User.find(1); post = user.posts.first %>
Avoid multiple Ruby statements in a single-line ERB tag. Split each statement into its own ERB tag for better readability. (erb-no-multiple-statements)

<%= user = User.find(1); user.name %>
Avoid multiple Ruby statements in a single-line ERB tag. Split each statement into its own ERB tag for better readability. (erb-no-multiple-statements)

<% a = 1; b = 2; c = 3 %>
Avoid multiple Ruby statements in a single-line ERB tag. Split each statement into its own ERB tag for better readability. (erb-no-multiple-statements)

References

• Ruby Style Guide - Semicolons