go/test/assign.go

// errorcheck

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Verify simple assignment errors are caught by the compiler.
// Does not compile.

package main

import "sync"

type T struct {
	int
	sync.Mutex
}

func main() {
	{
		var x, y sync.Mutex
		x = y // ok
		_ = x
	}
	{
		var x, y T
		x = y // ok
		_ = x
	}
	{
		var x, y [2]sync.Mutex
		x = y // ok
		_ = x
	}
	{
		var x, y [2]T
		x = y // ok
		_ = x
	}
	{
		x := sync.Mutex{0, 0} // ERROR "assignment.*Mutex"
		_ = x
	}
	{
		x := sync.Mutex{key: 0} // ERROR "(unknown|assignment).*Mutex"
		_ = x
	}
	{
		x := &sync.Mutex{} // ok
		var y sync.Mutex   // ok
		y = *x             // ok
		*x = y             // ok
		_ = x
		_ = y
	}
	{
		var x = 1
		{
			x, x := 2, 3 // ERROR "x repeated on left side of :="
			_ = x
		}
		_ = x
	}
	{
		a, a := 1, 2 // ERROR "a repeated on left side of :="
		_ = a
	}
}