exhaustive

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exhaustive

Check exhaustiveness of enum switch statements and map literals in Go source code.

go install github.com/nishanths/exhaustive/cmd/exhaustive@latest

For docs on the flags, the definition of enum, and the definition of exhaustiveness, see godocs.io.

For the changelog, see CHANGELOG in the wiki.

The package provides an Analyzer that follows the guidelines in the go/analysis package; this should make it possible to integrate exhaustive with your own analysis driver program.

Bugs

exhaustive does not report missing cases if the switch statement switches on a type parameterized type. See this issue for details.

Example

Given the enum

package token

type Token int

const (
	Add Token = iota
	Subtract
	Multiply
	Quotient
	Remainder
)

and the code

package calc

import "token"

func f(t token.Token) {
	switch t {
	case token.Add:
	case token.Subtract:
	case token.Multiply:
	default:
	}
}

func g(t token.Token) string {
	return map[token.Token]string{
		token.Add:      "add",
		token.Subtract: "subtract",
		token.Multiply: "multiply",
	}[t]
}

running exhaustive will print

calc.go:6:2: missing cases in switch of type token.Token: Quotient, Remainder
calc.go:15:9: missing map keys of type token.Token: Quotient, Remainder

Contributing

Issues and pull requests are welcome. Before making a substantial change, please discuss it in an issue.