Fix serialization of nested objects

index.js

@@ -24,11 +24,7 @@ function build (schema, options) {
   var code = `
     'use strict'
   `
-  // used to support patternProperties and additionalProperties
-  // they need to check if a field belongs to the properties in the schema
-  code += `
-    var properties = ${JSON.stringify(schema.properties)} || {}
-  `
+
   code += `
     ${$asString.toString()}
     ${$asStringSmall.toString()}
@@ -218,6 +214,7 @@ function $asStringSmall (str) {
 function addPatternProperties (schema, externalSchema, fullSchema) {
   var pp = schema.patternProperties
   var code = `
+      var properties = ${JSON.stringify(schema.properties)} || {}
       var keys = Object.keys(obj)
       for (var i = 0; i < keys.length; i++) {
         if (properties[keys[i]]) continue
@@ -368,6 +365,7 @@ function additionalProperty (schema, externalSchema, fullSchema) {
 
 function addAdditionalProperties (schema, externalSchema, fullSchema) {
   return `
+      var properties = ${JSON.stringify(schema.properties)} || {}
       var keys = Object.keys(obj)
       for (var i = 0; i < keys.length; i++) {
         if (properties[keys[i]]) continue

test/nestedObjects.test.js

@@ -0,0 +1,36 @@
+'use strict'
+
+const test = require('tap').test
+const build = require('..')
+
+test('nested objects with same properties', (t) => {
+  t.plan(1)
+
+  const schema = {
+    title: 'nested objects with same properties',
+    type: 'object',
+    properties: {
+      stringProperty: {
+        type: 'string'
+      },
+      objectProperty: {
+        type: 'object',
+        additionalProperties: true
+      }
+    }
+  }
+  const stringify = build(schema)
+
+  try {
+    const value = stringify({
+      stringProperty: 'string1',
+      objectProperty: {
+        stringProperty: 'string2',
+        numberProperty: 42
+      }
+    })
+    t.is(value, '{"stringProperty":"string1","objectProperty":{"stringProperty":"string2","numberProperty":42}}')
+  } catch (e) {
+    t.fail()
+  }
+})