go/test/convert2.go

// errorcheck

// Copyright 2016 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.

// Test various valid and invalid struct assignments and conversions.
// Does not compile.

package main

type I interface {
	m()
}

// conversions between structs

func _() {
	type S struct{}
	type T struct{}
	var s S
	var t T
	var u struct{}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u
	s = S(s)
	s = S(t)
	s = S(u)
	t = u
	t = T(u)
}

func _() {
	type S struct{ x int }
	type T struct {
		x int "foo"
	}
	var s S
	var t T
	var u struct {
		x int "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = S(s)
	s = S(t)
	s = S(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = T(u)
}

func _() {
	type E struct{ x int }
	type S struct{ x E }
	type T struct {
		x E "foo"
	}
	var s S
	var t T
	var u struct {
		x E "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = S(s)
	s = S(t)
	s = S(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = T(u)
}

func _() {
	type S struct {
		x struct {
			x int "foo"
		}
	}
	type T struct {
		x struct {
			x int "bar"
		} "foo"
	}
	var s S
	var t T
	var u struct {
		x struct {
			x int "bar"
		} "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = S(s)
	s = S(t)
	s = S(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = T(u)
}

func _() {
	type E1 struct {
		x int "foo"
	}
	type E2 struct {
		x int "bar"
	}
	type S struct{ x E1 }
	type T struct {
		x E2 "foo"
	}
	var s S
	var t T
	var u struct {
		x E2 "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = S(s)
	s = S(t) // ERROR "cannot convert"
	s = S(u) // ERROR "cannot convert"
	t = u    // ERROR "cannot use .* in assignment|incompatible type"
	t = T(u)
}

func _() {
	type E struct{ x int }
	type S struct {
		f func(struct {
			x int "foo"
		})
	}
	type T struct {
		f func(struct {
			x int "bar"
		})
	}
	var s S
	var t T
	var u struct{ f func(E) }
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = S(s)
	s = S(t)
	s = S(u) // ERROR "cannot convert"
	t = u    // ERROR "cannot use .* in assignment|incompatible type"
	t = T(u) // ERROR "cannot convert"
}

// conversions between pointers to structs

func _() {
	type S struct{}
	type T struct{}
	var s *S
	var t *T
	var u *struct{}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u)
}

func _() {
	type S struct{ x int }
	type T struct {
		x int "foo"
	}
	var s *S
	var t *T
	var u *struct {
		x int "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u)
}

func _() {
	type E struct{ x int }
	type S struct{ x E }
	type T struct {
		x E "foo"
	}
	var s *S
	var t *T
	var u *struct {
		x E "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u)
}

func _() {
	type S struct {
		x struct {
			x int "foo"
		}
	}
	type T struct {
		x struct {
			x int "bar"
		} "foo"
	}
	var s *S
	var t *T
	var u *struct {
		x struct {
			x int "bar"
		} "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u)
	t = u // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u)
}

func _() {
	type E1 struct {
		x int "foo"
	}
	type E2 struct {
		x int "bar"
	}
	type S struct{ x E1 }
	type T struct {
		x E2 "foo"
	}
	var s *S
	var t *T
	var u *struct {
		x E2 "bar"
	}
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t) // ERROR "cannot convert"
	s = (*S)(u) // ERROR "cannot convert"
	t = u       // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u)
}

func _() {
	type E struct{ x int }
	type S struct {
		f func(struct {
			x int "foo"
		})
	}
	type T struct {
		f func(struct {
			x int "bar"
		})
	}
	var s *S
	var t *T
	var u *struct{ f func(E) }
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u) // ERROR "cannot convert"
	t = u       // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u) // ERROR "cannot convert"
}

func _() {
	type E struct{ x int }
	type S struct {
		f func(*struct {
			x int "foo"
		})
	}
	type T struct {
		f func(*struct {
			x int "bar"
		})
	}
	var s *S
	var t *T
	var u *struct{ f func(E) }
	s = s
	s = t // ERROR "cannot use .* in assignment|incompatible type"
	s = u // ERROR "cannot use .* in assignment|incompatible type"
	s = (*S)(s)
	s = (*S)(t)
	s = (*S)(u) // ERROR "cannot convert"
	t = u       // ERROR "cannot use .* in assignment|incompatible type"
	t = (*T)(u) // ERROR "cannot convert"
}

func _() {
	var s []byte
	_ = ([4]byte)(s)
	_ = (*[4]byte)(s)

	type A [4]byte
	_ = (A)(s)
	_ = (*A)(s)

	type P *[4]byte
	_ = (P)(s)
	_ = (*P)(s) // ERROR "cannot convert"
}