openapi3: fix an infinite loop that may have been introduced in getki…

…n#700

Signed-off-by: Pierre Fenoll <pierrefenoll@gmail.com>

openapi3/issue542_test.go

@@ -7,8 +7,31 @@ import (
 )
 
 func TestIssue542(t *testing.T) {
+	spec := []byte(`
+openapi: '3.0.0'
+info:
+  version: '1.0.0'
+  title: Swagger Petstore
+  license:
+    name: MIT
+servers:
+- url: http://petstore.swagger.io/v1
+paths: {}
+components:
+  schemas:
+    Cat:
+      anyOf:
+      - $ref: '#/components/schemas/Kitten'
+      - type: object
+    Kitten:
+      type: string
+`[1:])
+
 	sl := NewLoader()
 
-	_, err := sl.LoadFromFile("testdata/issue542.yml")
+	doc, err := sl.LoadFromData(spec)
+	require.NoError(t, err)
+
+	doc.Validate(sl.Context)
 	require.NoError(t, err)
 }

openapi3/issue615_test.go

@@ -10,10 +10,14 @@ import (
 
 func TestIssue615(t *testing.T) {
 	{
+		var old int
+		old, openapi3.CircularReferenceCounter = openapi3.CircularReferenceCounter, 1
+		defer func() { openapi3.CircularReferenceCounter = old }()
+
 		loader := openapi3.NewLoader()
 		loader.IsExternalRefsAllowed = true
 		_, err := loader.LoadFromFile("testdata/recursiveRef/issue615.yml")
-		require.NoError(t, err)
+		require.ErrorContains(t, err, openapi3.CircularReferenceError)
 	}
 
 	var old int
@@ -22,6 +26,9 @@ func TestIssue615(t *testing.T) {
 
 	loader := openapi3.NewLoader()
 	loader.IsExternalRefsAllowed = true
-	_, err := loader.LoadFromFile("testdata/recursiveRef/issue615.yml")
+	doc, err := loader.LoadFromFile("testdata/recursiveRef/issue615.yml")
+	require.NoError(t, err)
+
+	doc.Validate(loader.Context)
 	require.NoError(t, err)
 }

openapi3/loader.go

@@ -504,7 +504,6 @@ func (loader *Loader) resolveHeaderRef(doc *T, component *HeaderRef, documentPat
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	value := component.Value
@@ -552,7 +551,6 @@ func (loader *Loader) resolveParameterRef(doc *T, component *ParameterRef, docum
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	value := component.Value
@@ -609,7 +607,6 @@ func (loader *Loader) resolveRequestBodyRef(doc *T, component *RequestBodyRef, d
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	value := component.Value
@@ -671,7 +668,6 @@ func (loader *Loader) resolveResponseRef(doc *T, component *ResponseRef, documen
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	value := component.Value
@@ -754,7 +750,6 @@ func (loader *Loader) resolveSchemaRef(doc *T, component *SchemaRef, documentPat
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 		if loader.visitedSchema == nil {
 			loader.visitedSchema = make(map[*Schema]struct{})
@@ -836,7 +831,6 @@ func (loader *Loader) resolveSecuritySchemeRef(doc *T, component *SecurityScheme
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	return nil
@@ -873,7 +867,6 @@ func (loader *Loader) resolveExampleRef(doc *T, component *ExampleRef, documentP
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	return nil
@@ -910,7 +903,6 @@ func (loader *Loader) resolveCallbackRef(doc *T, component *CallbackRef, documen
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	value := component.Value
@@ -957,7 +949,6 @@ func (loader *Loader) resolveLinkRef(doc *T, component *LinkRef, documentPath *u
 				return err
 			}
 			component.Value = resolved.Value
-			return nil
 		}
 	}
 	return nil
@@ -999,10 +990,7 @@ func (loader *Loader) resolvePathItemRef(doc *T, pathItem *PathItem, documentPat
 		}
 		pathItem.Ref = ref
 	}
-	return loader.resolvePathItemRefContinued(doc, pathItem, documentPath)
-}
 
-func (loader *Loader) resolvePathItemRefContinued(doc *T, pathItem *PathItem, documentPath *url.URL) (err error) {
 	for _, parameter := range pathItem.Parameters {
 		if err = loader.resolveParameterRef(doc, parameter, documentPath); err != nil {
 			return