Allow setting a maxLength and maxItems to limit generatioN

Closes #199

README.md

@@ -401,6 +401,8 @@ You may define following options for `jsf` that alter its behavior:
 
 - `failOnInvalidTypes`: boolean - don't throw exception when invalid type passed
 - `defaultInvalidTypeProduct`: - default value generated for a schema with invalid type (works only if `failOnInvalidTypes` is set to `false`)
+- `maxItems`: number - Configure a maximum amount of items to generate in an array. This will override the maximum items found inside a JSON Schema.
+- `maxLength`: number - Configure a maximum length to allow generating strings for. This will override the maximum length found inside a JSON Schema.
 
 Set options just as below:
 

ts/class/OptionRegistry.ts

@@ -12,6 +12,8 @@ class OptionRegistry extends Registry<Option> {
     this.data['failOnInvalidTypes'] = true;
     this.data['defaultInvalidTypeProduct'] = null;
     this.data['useDefaultValue'] = false;
+    this.data['maxItems'] = null;
+    this.data['maxLength'] = null;
   }
 }
 

ts/types/array.ts

 import random = require('../core/random');
 import utils = require('../core/utils');
 import ParseError = require('../core/error');
+import option = require('../api/option');
 
 // TODO provide types
 function unique(path: SchemaPath, items, value, sample, resolve, traverseCallback: Function) {
@@ -56,7 +57,22 @@ var arrayType: FTypeGenerator = function arrayType(value: IArraySchema, path: Sc
     }));
   }
 
-  var length: number = random.number(value.minItems, value.maxItems, 1, 5),
+  var minItems = value.minItems;
+  var maxItems = value.maxItems;
+
+  if (option('maxItems')) {
+    // Don't allow user to set max items above our maximum
+    if (maxItems && maxItems > option('maxItems')) {
+      maxItems = option('maxItems');
+    }
+
+    // Don't allow user to set min items above our maximum
+    if (minItems && minItems > option('maxItems')) {
+      minItems = maxItems;
+    }
+  }
+
+  var length: number = random.number(minItems, maxItems, 1, 5),
       // TODO below looks bad. Should additionalItems be copied as-is?
       sample: Object = typeof value.additionalItems === 'object' ? value.additionalItems : {};
 

ts/types/string.ts

@@ -3,6 +3,7 @@ import ipv4 = require('../generators/ipv4');
 import dateTime = require('../generators/dateTime');
 import coreFormat = require('../generators/coreFormat');
 import format = require('../api/format');
+import option = require('../api/option');
 
 import container = require('../class/Container');
 var randexp = container.get('randexp');
@@ -33,7 +34,22 @@ var stringType: FTypeGenerator = function stringType(value: IStringSchema): stri
   } else if (value.pattern) {
     return randexp(value.pattern);
   } else {
-    return thunk(value.minLength, value.maxLength);
+    var minLength = value.minLength;
+    var maxLength = value.maxLength;
+
+    if (option('maxLength')) {
+      // Don't allow user to set max length above our maximum
+      if (maxLength && maxLength > option('maxLength')) {
+        maxLength = option('maxLength');
+      }
+
+      // Don't allow user to set min length above our maximum
+      if (minLength && minLength > option('maxLength')) {
+        minLength = option('maxLength');
+      }
+    }
+
+    return thunk(minLength, maxLength);
   }
 };