fix crash on load (#795)

Author: Reuven Harrison

openapi3/issue794_test.go

@@ -0,0 +1,15 @@
+package openapi3
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestCrashOnLoad(t *testing.T) {
+	loader := NewLoader()
+	doc, err := loader.LoadFromFile("testdata/issue794.yml")
+	require.NoError(t, err)
+	err = doc.Validate(loader.Context)
+	require.NoError(t, err)
+}

openapi3/loader.go

@@ -615,6 +615,9 @@ func (loader *Loader) resolveRequestBodyRef(doc *T, component *RequestBodyRef, d
 	}
 
 	for _, contentType := range value.Content {
+		if contentType == nil {
+			continue
+		}
 		examples := make([]string, 0, len(contentType.Examples))
 		for name := range contentType.Examples {
 			examples = append(examples, name)

openapi3/testdata/issue794.yml

@@ -0,0 +1,13 @@
+openapi: 3.0.1
+info:
+  title: Swagger API
+  version: v1
+paths:
+  /test:
+    post:
+      requestBody:
+        content:
+          application/json:
+      responses:
+        "200":
+          description: description