1
0
mirror of https://github.com/golang/go synced 2024-11-25 16:27:57 -07:00
go/test/fixedbugs/issue48558.go
Robert Griesemer 0626ac064d cmd/compile: restore original assignment error messages
When used with the compiler, types2 will report assignment error
messages that closely match what the compiler type checker (types1)
produces.

Also, mark lhs variables as used in invalid variable initializations
to avoid a class of follow-on errors.

Fixes #48558.

Change-Id: I92d1de006c66b3a2364bb1bea773a312963afe75
Reviewed-on: https://go-review.googlesource.com/c/go/+/351669
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
2021-09-23 19:41:41 +00:00

78 lines
2.9 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
func _(a, b, c int) {
_ = a
_ = a, b // ERROR "assignment mismatch: 1 variable but 2 values"
_ = a, b, c // ERROR "assignment mismatch: 1 variable but 3 values"
_, _ = a // ERROR "assignment mismatch: 2 variables but 1 value"
_, _ = a, b
_, _ = a, b, c // ERROR "assignment mismatch: 2 variables but 3 values"
_, _, _ = a // ERROR "assignment mismatch: 3 variables but 1 value"
_, _, _ = a, b // ERROR "assignment mismatch: 3 variables but 2 values"
_, _, _ = a, b, c
}
func f1() int
func f2() (int, int)
func f3() (int, int, int)
func _() {
_ = f1()
_ = f2() // ERROR "assignment mismatch: 1 variable but f2 returns 2 values"
_ = f3() // ERROR "assignment mismatch: 1 variable but f3 returns 3 values"
_, _ = f1() // ERROR "assignment mismatch: 2 variables but f1 returns 1 value"
_, _ = f2()
_, _ = f3() // ERROR "assignment mismatch: 2 variables but f3 returns 3 values"
_, _, _ = f1() // ERROR "assignment mismatch: 3 variables but f1 returns 1 value"
_, _, _ = f2() // ERROR "assignment mismatch: 3 variables but f2 returns 2 values"
_, _, _ = f3()
// test just a few := cases as they use the same code as the = case
a1 := f3() // ERROR "assignment mismatch: 1 variable but f3 returns 3 values"
a2, b2 := f1() // ERROR "assignment mismatch: 2 variables but f1 returns 1 value"
a3, b3, c3 := f2() // ERROR "assignment mismatch: 3 variables but f2 returns 2 values"
}
type T struct{}
func (T) f1() int
func (T) f2() (int, int)
func (T) f3() (int, int, int)
func _(x T) {
_ = x.f1()
_ = x.f2() // ERROR "assignment mismatch: 1 variable but .\.f2 returns 2 values"
_ = x.f3() // ERROR "assignment mismatch: 1 variable but .\.f3 returns 3 values"
_, _ = x.f1() // ERROR "assignment mismatch: 2 variables but .\.f1 returns 1 value"
_, _ = x.f2()
_, _ = x.f3() // ERROR "assignment mismatch: 2 variables but .\.f3 returns 3 values"
_, _, _ = x.f1() // ERROR "assignment mismatch: 3 variables but .\.f1 returns 1 value"
_, _, _ = x.f2() // ERROR "assignment mismatch: 3 variables but .\.f2 returns 2 values"
_, _, _ = x.f3()
// test just a few := cases as they use the same code as the = case
a1 := x.f3() // ERROR "assignment mismatch: 1 variable but .\.f3 returns 3 values"
a2, b2 := x.f1() // ERROR "assignment mismatch: 2 variables but .\.f1 returns 1 value"
a3, b3, c3 := x.f2() // ERROR "assignment mismatch: 3 variables but .\.f2 returns 2 values"
}
// some one-off cases
func _() {
_ = (f2)
_ = f1(), 2 // ERROR "assignment mismatch: 1 variable but 2 values"
_, _ = (f1()), f2() // ERROR "multiple-value f2\(\) .*in single-value context"
_, _, _ = f3(), 3 // ERROR "assignment mismatch: 3 variables but 2 values|multiple-value f3\(\) .*in single-value context"
}