one-class-per-file

Flags files that declare more than one class following Garmin’s Monkey C coding conventions.

Rationale

Keeping each class in its own file makes the file name a reliable index of its primary type, lets readers locate code by filename alone, and keeps related members (fields, methods, helper functions) grouped together. Co-locating two classes usually means one of them is incidental and should move to its own file.

What triggers

Anything after the first class declaration anywhere in the file. The rule counts across module boundaries, so a file with two top-level classes, a module containing two classes, or two nested modules each holding a class all trigger.

What does not trigger

A file with exactly one class, regardless of how many functions, modules, typedefs, or using declarations sit alongside it.

Example

Before:

class Foo {
    function foo() {}
}

class Bar {
    function bar() {}
}

The rule reports Bar as the offending second class. There is no auto-fix — moving Bar to its own file requires choosing a file name and deciding what context (imports, module wrapping) to copy across.