Merge pull request #469 from visualfc/validtype

validType for check recursive

builtin_test.go

@@ -1386,4 +1386,26 @@ func TestAssignableUntyped(t *testing.T) {
 	}
 }
 
+func TestValidType(t *testing.T) {
+	var errs []error
+	conf := &Config{
+		HandleErr: func(err error) {
+			errs = append(errs, err)
+		},
+	}
+	pkg := NewPackage("", "foo", conf)
+	typeA := types.NewNamed(types.NewTypeName(token.NoPos, pkg.Types, "A", nil), nil, nil)
+	typeB := types.NewNamed(types.NewTypeName(token.NoPos, pkg.Types, "B", nil), nil, nil)
+	typeA.SetUnderlying(types.NewStruct([]*types.Var{
+		types.NewField(token.NoPos, pkg.Types, "B", typeB, true), // Embed B.
+	}, nil))
+	typeB.SetUnderlying(types.NewStruct([]*types.Var{
+		types.NewField(token.NoPos, pkg.Types, "A", typeA, true), // Embed A.
+	}, nil))
+	pkg.ValidType(typeA)
+	if len(errs) == 0 {
+		t.Fatal("TestValidType: no error?")
+	}
+}
+
 // ----------------------------------------------------------------------------

validtype.go

@@ -0,0 +1,31 @@
+/*
+ Copyright 2024 The GoPlus Authors (goplus.org)
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+     http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+package gogen
+
+import (
+	"go/types"
+	_ "unsafe"
+)
+
+//go:linkname validType go/types.(*Checker).validType
+func validType(check *types.Checker, typ *types.Named)
+
+// ValidType verifies that the given type does not "expand" indefinitely
+// producing a cycle in the type graph. Cycles are detected by marking
+// defined types.
+func (pkg *Package) ValidType(typ *types.Named) {
+	conf := &types.Config{Error: pkg.conf.HandleErr}
+	checker := types.NewChecker(conf, pkg.Fset, pkg.Types, nil)
+	validType(checker, typ)
+}