go/types, types2: print qualified object names in cycle errors
Fixes #50788.
Change-Id: Id1ed7d9c0687e3005e28598373fd5634178c78ca
Reviewed-on: https://go-review.googlesource.com/c/go/+/413895
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
diff --git a/src/cmd/compile/internal/types2/decl.go b/src/cmd/compile/internal/types2/decl.go
index 0bc5f9f..1db28fc 100644
--- a/src/cmd/compile/internal/types2/decl.go
+++ b/src/cmd/compile/internal/types2/decl.go
@@ -5,6 +5,7 @@
package types2
import (
+ "bytes"
"cmd/compile/internal/syntax"
"fmt"
"go/constant"
@@ -303,11 +304,23 @@
// cycleError reports a declaration cycle starting with
// the object in cycle that is "first" in the source.
func (check *Checker) cycleError(cycle []Object) {
+ // name returns the (possibly qualified) object name.
+ // This is needed because with generic types, cycles
+ // may refer to imported types. See issue #50788.
+ // TODO(gri) Thus functionality is used elsewhere. Factor it out.
+ name := func(obj Object) string {
+ var buf bytes.Buffer
+ writePackage(&buf, obj.Pkg(), check.qualifier)
+ buf.WriteString(obj.Name())
+ return buf.String()
+ }
+
// TODO(gri) Should we start with the last (rather than the first) object in the cycle
// since that is the earliest point in the source where we start seeing the
// cycle? That would be more consistent with other error messages.
i := firstInSrc(cycle)
obj := cycle[i]
+ objName := name(obj)
// If obj is a type alias, mark it as valid (not broken) in order to avoid follow-on errors.
tname, _ := obj.(*TypeName)
if tname != nil && tname.IsAlias() {
@@ -315,19 +328,20 @@
}
var err error_
if tname != nil && check.conf.CompilerErrorMessages {
- err.errorf(obj, "invalid recursive type %s", obj.Name())
+ err.errorf(obj, "invalid recursive type %s", objName)
} else {
- err.errorf(obj, "illegal cycle in declaration of %s", obj.Name())
+ err.errorf(obj, "illegal cycle in declaration of %s", objName)
}
for range cycle {
- err.errorf(obj, "%s refers to", obj.Name())
+ err.errorf(obj, "%s refers to", objName)
i++
if i >= len(cycle) {
i = 0
}
obj = cycle[i]
+ objName = name(obj)
}
- err.errorf(obj, "%s", obj.Name())
+ err.errorf(obj, "%s", objName)
check.report(&err)
}
diff --git a/src/go/types/decl.go b/src/go/types/decl.go
index c176042..829aee7 100644
--- a/src/go/types/decl.go
+++ b/src/go/types/decl.go
@@ -5,6 +5,7 @@
package types
import (
+ "bytes"
"fmt"
"go/ast"
"go/constant"
@@ -302,30 +303,43 @@
// cycleError reports a declaration cycle starting with
// the object in cycle that is "first" in the source.
func (check *Checker) cycleError(cycle []Object) {
+ // name returns the (possibly qualified) object name.
+ // This is needed because with generic types, cycles
+ // may refer to imported types. See issue #50788.
+ // TODO(gri) Thus functionality is used elsewhere. Factor it out.
+ name := func(obj Object) string {
+ var buf bytes.Buffer
+ writePackage(&buf, obj.Pkg(), check.qualifier)
+ buf.WriteString(obj.Name())
+ return buf.String()
+ }
+
// TODO(gri) Should we start with the last (rather than the first) object in the cycle
// since that is the earliest point in the source where we start seeing the
// cycle? That would be more consistent with other error messages.
i := firstInSrc(cycle)
obj := cycle[i]
+ objName := name(obj)
// If obj is a type alias, mark it as valid (not broken) in order to avoid follow-on errors.
tname, _ := obj.(*TypeName)
if tname != nil && tname.IsAlias() {
check.validAlias(tname, Typ[Invalid])
}
if tname != nil && compilerErrorMessages {
- check.errorf(obj, _InvalidDeclCycle, "invalid recursive type %s", obj.Name())
+ check.errorf(obj, _InvalidDeclCycle, "invalid recursive type %s", objName)
} else {
- check.errorf(obj, _InvalidDeclCycle, "illegal cycle in declaration of %s", obj.Name())
+ check.errorf(obj, _InvalidDeclCycle, "illegal cycle in declaration of %s", objName)
}
for range cycle {
- check.errorf(obj, _InvalidDeclCycle, "\t%s refers to", obj.Name()) // secondary error, \t indented
+ check.errorf(obj, _InvalidDeclCycle, "\t%s refers to", objName) // secondary error, \t indented
i++
if i >= len(cycle) {
i = 0
}
obj = cycle[i]
+ objName = name(obj)
}
- check.errorf(obj, _InvalidDeclCycle, "\t%s", obj.Name())
+ check.errorf(obj, _InvalidDeclCycle, "\t%s", objName)
}
// firstInSrc reports the index of the object with the "smallest"
diff --git a/test/fixedbugs/issue50788.dir/a.go b/test/fixedbugs/issue50788.dir/a.go
new file mode 100644
index 0000000..0f786d4
--- /dev/null
+++ b/test/fixedbugs/issue50788.dir/a.go
@@ -0,0 +1,9 @@
+// Copyright 2022 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 a
+
+type T[P any] struct {
+ _ P
+}
diff --git a/test/fixedbugs/issue50788.dir/b.go b/test/fixedbugs/issue50788.dir/b.go
new file mode 100644
index 0000000..e17afc7
--- /dev/null
+++ b/test/fixedbugs/issue50788.dir/b.go
@@ -0,0 +1,9 @@
+// Copyright 2022 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 b
+
+import "./a"
+
+type T a.T[T] // ERROR "invalid recursive type T\n.*T refers to\n.*a\.T refers to\n.*T"
diff --git a/test/fixedbugs/issue50788.go b/test/fixedbugs/issue50788.go
new file mode 100644
index 0000000..24d0eb0
--- /dev/null
+++ b/test/fixedbugs/issue50788.go
@@ -0,0 +1,7 @@
+// errorcheckdir
+
+// Copyright 2022 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 ignored
