getVariableValues populates only valid values

Author: langpavel

src/execution/values.js

@@ -43,7 +43,10 @@ export function getVariableValues(
 ): { [key: string]: mixed } {
   return definitionASTs.reduce((values, defAST) => {
     const varName = defAST.variable.name.value;
-    values[varName] = getVariableValue(schema, defAST, inputs[varName]);
+    const value = getVariableValue(schema, defAST, inputs[varName]);
+    if (value !== undefined && value === value) {
+      values[varName] = value;
+    }
     return values;
   }, {});
 }