astFromNode does not converts NonNull values to NullValue

Author: langpavel

src/utilities/__tests__/astFromValue-test.js

@@ -19,6 +19,7 @@ import {
   GraphQLString,
   GraphQLBoolean,
   GraphQLID,
+  GraphQLNonNull,
 } from '../../type';
 
 
@@ -149,6 +150,13 @@ describe('astFromValue', () => {
     );
   });
 
+  it('does not converts NonNull values to NullValue', () => {
+    const NonNullBoolean = new GraphQLNonNull(GraphQLBoolean);
+    expect(astFromValue(null, NonNullBoolean)).to.deep.equal(
+      null
+    );
+  });
+
   const complexValue = { someArbitrary: 'complexValue' };
 
   const myEnum = new GraphQLEnumType({

src/utilities/astFromValue.js

@@ -71,9 +71,11 @@ export function astFromValue(
   const _value = value;
 
   if (type instanceof GraphQLNonNull) {
-    // Note: we're not checking that the result is non-null.
-    // This function is not responsible for validating the input value.
-    return astFromValue(_value, type.ofType);
+    const astValue = astFromValue(_value, type.ofType);
+    if (astValue && astValue.kind === NULL) {
+      return null;
+    }
+    return astValue;
   }
 
   // only explicit null, not undefined, NaN