switch-check is a tool for validating that switch statements contain all enum values.

go get -u github.com/elliotchance/switch-check

switch-check [options] [files or folders...]

  -show-enums
        Show all enums. Useful for debugging.
  -verbose
        Show all files processed.

package test

type Foo int

const (
	FooA Foo = iota
	FooB
)

const FooC = Foo(17)
const FooD = FooC
var FooE = Foo(-1)

func fooMissingSomeValues() {
	foo := FooB

	switch foo {
	case FooA:
	case FooC, FooD:
	}
}

Run with switch-check will output the error:

./test/foo.go:33:2 switch is missing cases for: FooB, FooE

1. Using expressions to produce enum values are not supported. This level of type inference requires the compiler (not just the AST). For example this will not be recognised as a enum value:

var EnumValueA = someFuncThatReturnsAnEnumValue()

2. Switch statements must only switch on the value and not contain expressions in case statements.