diff options
Diffstat (limited to 'test/typeparam/ifaceconv.go')
-rw-r--r-- | test/typeparam/ifaceconv.go | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/test/typeparam/ifaceconv.go b/test/typeparam/ifaceconv.go new file mode 100644 index 0000000..4dfc68f --- /dev/null +++ b/test/typeparam/ifaceconv.go @@ -0,0 +1,83 @@ +// run + +// 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. + +// Test that we can convert type parameters to both empty +// and nonempty interfaces, and named and nonnamed versions +// thereof. + +package main + +import "fmt" + +type E interface{} + +func f[T any](x T) interface{} { + var i interface{} = x + return i +} + +func fs[T any](x T) interface{} { + y := []T{x} + var i interface{} = y + return i +} + +func g[T any](x T) E { + var i E = x + return i +} + +type C interface { + foo() int +} + +type myInt int + +func (x myInt) foo() int { + return int(x + 1) +} + +func h[T C](x T) interface{ foo() int } { + var i interface{ foo() int } = x + return i +} +func i[T C](x T) C { + var i C = x // conversion in assignment + return i +} + +func j[T C](t T) C { + return C(t) // explicit conversion +} + +func js[T any](x T) interface{} { + y := []T{x} + return interface{}(y) +} + +func main() { + if got, want := f[int](7), 7; got != want { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := fs[int](7), []int{7}; got.([]int)[0] != want[0] { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := g[int](7), 7; got != want { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := h[myInt](7).foo(), 8; got != want { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := i[myInt](7).foo(), 8; got != want { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := j[myInt](7).foo(), 8; got != want { + panic(fmt.Sprintf("got %d want %d", got, want)) + } + if got, want := js[int](7), []int{7}; got.([]int)[0] != want[0] { + panic(fmt.Sprintf("got %d want %d", got, want)) + } +} |