go/test/fixedbugs/issue48471.go
Robert Griesemer abf9b112fd go/types, types2: more systematic use of Checker.use und useLHS
This CL re-introduces useLHS because we don't want to suppress
correct "declared but not used" errors for variables that only
appear on the LHS of an assignment (using Checker.use would mark
them as used).

This CL also adjusts a couple of places where types2 differed
from go/types (and suppressed valid "declared and not used"
errors). Now those errors are surfaced. Adjusted a handful of
tests accordingly.

Change-Id: Ia555139a05049887aeeec9e5221b1f41432c1a57
Reviewed-on: https://go-review.googlesource.com/c/go/+/478635
Reviewed-by: Robert Griesemer <gri@google.com>
Auto-Submit: Robert Griesemer <gri@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Robert Griesemer <gri@google.com>
2023-03-28 14:28:33 +00:00

57 lines
2.2 KiB
Go

// errorcheck
// Copyright 2021 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.
package p
type I interface{ M(int) }
type T struct{}
type T2 struct{}
func (*T2) m(int)
type T3 struct{}
func (*T3) M(string) {}
type T4 struct{}
func (*T4) M(int)
type T5 struct{}
func (T5) m(int) {}
type T6 struct{}
func (T6) m(int) string { return "" }
func f(I)
func g() {
f(new(T)) // ERROR "cannot use new\(T\) \(.*type \*T\) as I value in argument to f: \*T does not implement I \(missing method M\)"
var i I
i = new(T) // ERROR "cannot use new\(T\) \(.*type \*T\) as I value in assignment: \*T does not implement I \(missing method M\)"
i = I(new(T)) // ERROR "cannot convert new\(T\) \(.*type \*T\) to type I: \*T does not implement I \(missing method M\)"
i = new(T2) // ERROR "cannot use new\(T2\) \(.*type \*T2\) as I value in assignment: \*T2 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
i = new(T3) // ERROR "cannot use new\(T3\) \(.*type \*T3\) as I value in assignment: \*T3 does not implement I \(wrong type for method M\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
i = T4{} // ERROR "cannot use T4\{\} \(.*type T4\) as I value in assignment: T4 does not implement I \(method M has pointer receiver\)"
i = new(I) // ERROR "cannot use new\(I\) \(.*type \*I\) as I value in assignment: \*I does not implement I \(type \*I is pointer to interface, not interface\)"
_ = i.(*T2) // ERROR "impossible type assertion: i.\(\*T2\)\n\t\*T2 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
_ = i.(*T3) // ERROR "impossible type assertion: i.\(\*T3\)\n\t\*T3 does not implement I \(wrong type for method M\)\n\t\thave M\(string\)\n\t\twant M\(int\)"
_ = i.(T5) // ERROR ""impossible type assertion: i.\(T5\)\n\tT5 does not implement I \(missing method M\)\n\t\thave m\(int\)\n\t\twant M\(int\)"
_ = i.(T6) // ERROR "impossible type assertion: i.\(T6\)\n\tT6 does not implement I \(missing method M\)\n\t\thave m\(int\) string\n\t\twant M\(int\)"
var t *T4
t = i // ERROR "cannot use i \(variable of type I\) as \*T4 value in assignment: need type assertion"
_ = t
}