Suggest directional channel parameters

[alexandear]

A linter for detecting function parameters of type chan T that are only used for sending or receiving, and suggests converting them to send-only chan<- T or receive-only <-chan T channel types.

Benefits of channel direction

• Type safety
• Explicit communication intent
• Preventing unintended operations
• Improved code readability

Example

This code

func worker(ch chan Job) {
    for job := range ch {
        process(job)
    }
}

should be suggested by a linter to

func worker(ch <-chan Job) {
    for job := range ch {
        process(job)
    }
}

Real world examples

• Refactor to use directional error channels lima-vm/lima#2617