Adds anyOf support

index.js

@@ -1,6 +1,7 @@
 'use strict'
 
 var fastSafeStringify = require('fast-safe-stringify')
+var Ajv = require('ajv')
 
 var uglify = null
 var isLong
@@ -87,10 +88,19 @@ function build (schema, options) {
     code = uglifyCode(code)
   }
 
+  var dependencies = []
+  var dependenciesName = []
   if (hasAdditionalPropertiesTrue(schema)) {
-    return (new Function('fastSafeStringify', code))(fastSafeStringify)
+    dependencies.push(fastSafeStringify)
+    dependenciesName.push('fastSafeStringify')
   }
-  return (new Function(code))()
+  if (hasAnyOf(schema)) {
+    dependencies.push(new Ajv())
+    dependenciesName.push('ajv')
+  }
+
+  dependenciesName.push(code)
+  return (Function.apply(null, dependenciesName).apply(null, dependencies))
 }
 
 function hasAdditionalPropertiesTrue (schema) {
@@ -107,6 +117,20 @@ function hasAdditionalPropertiesTrue (schema) {
   return false
 }
 
+function hasAnyOf (schema) {
+  if ('anyOf' in schema) { return true }
+
+  var objectKeys = Object.keys(schema)
+  for (var i = 0; i < objectKeys.length; i++) {
+    var value = schema[objectKeys[i]]
+    if (typeof value === 'object') {
+      if (hasAnyOf(value)) { return true }
+    }
+  }
+
+  return false
+}
+
 function $asNull () {
   return 'null'
 }
@@ -517,8 +541,22 @@ function nested (laterCode, name, key, schema, externalSchema, fullSchema, subKe
       funcName = (name + key + subKey).replace(/[-.\[\]]/g, '') // eslint-disable-line
       laterCode = buildArray(schema, laterCode, funcName, externalSchema, fullSchema)
       code += `
-        json += ${funcName}(obj${accessor})
-      `
+json += ${funcName}(obj${accessor})
+    `
+      break
+
+    case undefined:
+      if ('anyOf' in schema) {
+        schema.anyOf.forEach((s, index) => {
+          code += `
+            ${index === 0 ? 'if' : 'else if'}(ajv.validate(${require('util').inspect(s, {depth: null})}, obj${accessor}))
+              ${nested(laterCode, name, key, s, externalSchema, fullSchema, subKey).code}
+          `
+        })
+        code += `
+          else json+= null
+        `
+      } else throw new Error(`${schema} unsupported`)
       break
     default:
       throw new Error(`${type} unsupported`)

package.json

@@ -4,6 +4,7 @@
   "description": "Stringify your JSON at max speed",
   "main": "index.js",
   "scripts": {
+    "benchmark": "node bench.js",
     "test": "standard && tap test/*.test.js"
   },
   "precommit": "test",
@@ -33,6 +34,7 @@
     "uglify-es": "^3.1.1"
   },
   "dependencies": {
+    "ajv": "^5.2.3",
     "fast-safe-stringify": "^1.2.0"
   }
 }

test/anyof.test.js

@@ -0,0 +1,41 @@
+'use strict'
+
+const test = require('tap').test
+const build = require('..')
+
+test('object with multiple types field', (t) => {
+  t.plan(2)
+
+  const schema = {
+    title: 'object with multiple types field',
+    type: 'object',
+    properties: {
+      str: {
+        'anyOf': [{
+          type: 'string'
+        }, {
+          type: 'boolean'
+        }]
+      }
+    }
+  }
+  const stringify = build(schema)
+
+  try {
+    const value = stringify({
+      str: 'string'
+    })
+    t.is(value, '{"str":"string"}')
+  } catch (e) {
+    t.fail()
+  }
+
+  try {
+    const value = stringify({
+      str: true
+    })
+    t.is(value, '{"str":true}')
+  } catch (e) {
+    t.fail()
+  }
+})