From 19b4142f240172d525f81d1b4efb5679f147b474 Mon Sep 17 00:00:00 2001 From: Rob Findley Date: Fri, 16 Jul 2021 20:22:59 -0400 Subject: [PATCH] [dev.typeparams] go/types: implement ch <- x where ch is of type parameter type This is a port of CL 333712 to go/types, adjusted for the different error reporting API and to position errors on the arrows. Fixes #43671 Change-Id: I7d2de249e86d272c89a046f60e632e75848ff865 Reviewed-on: https://go-review.googlesource.com/c/go/+/335076 Trust: Robert Findley Run-TryBot: Robert Findley TryBot-Result: Go Bot Reviewed-by: Robert Griesemer --- src/go/types/stmt.go | 36 ++++++++++------- .../types/testdata/fixedbugs/issue47115.go2 | 40 +++++++++++++++++++ 2 files changed, 62 insertions(+), 14 deletions(-) create mode 100644 src/go/types/testdata/fixedbugs/issue47115.go2 diff --git a/src/go/types/stmt.go b/src/go/types/stmt.go index 53fccb0a64..0f0a2e4d9f 100644 --- a/src/go/types/stmt.go +++ b/src/go/types/stmt.go @@ -361,25 +361,33 @@ func (check *Checker) stmt(ctxt stmtContext, s ast.Stmt) { check.errorf(&x, code, "%s %s", &x, msg) case *ast.SendStmt: - var ch, x operand + var ch, val operand check.expr(&ch, s.Chan) - check.expr(&x, s.Value) - if ch.mode == invalid || x.mode == invalid { + check.expr(&val, s.Value) + if ch.mode == invalid || val.mode == invalid { return } - - tch := asChan(ch.typ) - if tch == nil { - check.invalidOp(inNode(s, s.Arrow), _InvalidSend, "cannot send to non-chan type %s", ch.typ) + var elem Type + if !underIs(ch.typ, func(u Type) bool { + uch, _ := u.(*Chan) + if uch == nil { + check.invalidOp(inNode(s, s.Arrow), _InvalidSend, "cannot send to non-channel %s", &ch) + return false + } + if uch.dir == RecvOnly { + check.invalidOp(inNode(s, s.Arrow), _InvalidSend, "cannot send to receive-only channel %s", &ch) + return false + } + if elem != nil && !Identical(uch.elem, elem) { + check.invalidOp(inNode(s, s.Arrow), _Todo, "channels of %s must have the same element type", &ch) + return false + } + elem = uch.elem + return true + }) { return } - - if tch.dir == RecvOnly { - check.invalidOp(inNode(s, s.Arrow), _InvalidSend, "cannot send to receive-only type %s", tch) - return - } - - check.assignment(&x, tch.elem, "send") + check.assignment(&val, elem, "send") case *ast.IncDecStmt: var op token.Token diff --git a/src/go/types/testdata/fixedbugs/issue47115.go2 b/src/go/types/testdata/fixedbugs/issue47115.go2 new file mode 100644 index 0000000000..6694219b54 --- /dev/null +++ b/src/go/types/testdata/fixedbugs/issue47115.go2 @@ -0,0 +1,40 @@ +// 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 C0 interface{ int } +type C1 interface{ chan int } +type C2 interface{ chan int | <-chan int } +type C3 interface{ chan int | chan float32 } +type C4 interface{ chan int | chan<- int } +type C5[T any] interface{ ~chan T | chan<- T } + +func _[T any](ch T) { + ch <- /* ERROR cannot send to non-channel */ 0 +} + +func _[T C0](ch T) { + ch <- /* ERROR cannot send to non-channel */ 0 +} + +func _[T C1](ch T) { + ch <- 0 +} + +func _[T C2](ch T) { + ch <-/* ERROR cannot send to receive-only channel */ 0 +} + +func _[T C3](ch T) { + ch <- /* ERROR channels of ch .* must have the same element type */ 0 +} + +func _[T C4](ch T) { + ch <- 0 +} + +func _[T C5[X], X any](ch T, x X) { + ch <- x +}