From: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Date: Wed, 20 Oct 2021 05:31:53 +0000 (+0700)
Subject: go/types: print assignment operation for invalid operation errors
X-Git-Tag: go1.18beta1~815
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=fca46d0b36c10250713ec0f4c9bf13d626f358d1;p=gostls13.git

go/types: print assignment operation for invalid operation errors

This is port of CL 357229 for types2 to go/types.

Change-Id: I35ed6b784969210a00ea5b36238df7d6b7fa18bc
Reviewed-on: https://go-review.googlesource.com/c/go/+/357230
Trust: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
---

diff --git a/src/go/types/expr.go b/src/go/types/expr.go
index fac5a5e31d..3a09dfd85f 100644
--- a/src/go/types/expr.go
+++ b/src/go/types/expr.go
@@ -1000,7 +1000,11 @@ func (check *Checker) binary(x *operand, e ast.Expr, lhs, rhs ast.Expr, op token
 			if e != nil {
 				posn = e
 			}
-			check.invalidOp(posn, _MismatchedTypes, "%s (mismatched types %s and %s)", e, x.typ, y.typ)
+			if e != nil {
+				check.invalidOp(posn, _MismatchedTypes, "%s (mismatched types %s and %s)", e, x.typ, y.typ)
+			} else {
+				check.invalidOp(posn, _MismatchedTypes, "%s %s= %s (mismatched types %s and %s)", lhs, op, rhs, x.typ, y.typ)
+			}
 		}
 		x.mode = invalid
 		return
diff --git a/src/go/types/testdata/fixedbugs/issue48472.go2 b/src/go/types/testdata/fixedbugs/issue48472.go2
index 5fefcaf22b..2d908f4c8b 100644
--- a/src/go/types/testdata/fixedbugs/issue48472.go2
+++ b/src/go/types/testdata/fixedbugs/issue48472.go2
@@ -9,3 +9,8 @@ func g() {
 	var i int
 	_ = s /* ERROR invalid operation: s \+ i \(mismatched types string and int\) */ + i
 }
+
+func f(i int) int {
+        i /* ERROR invalid operation: i \+= "1" \(mismatched types int and untyped string\) */ += "1"
+        return i
+}