add support for disjoint union types (fix #27)

Author: bcherny

src/index.ts

@@ -7,7 +7,7 @@ import { join, parse, ParsedPath, resolve } from 'path'
 
 enum RuleType {
   'Any', 'TypedArray', 'Enum', 'AllOf', 'AnyOf', 'Reference', 'NamedSchema', 'AnonymousSchema',
-  'String', 'Number', 'Void', 'Object', 'Array', 'Boolean', 'Literal'
+  'String', 'Number', 'Void', 'Object', 'Array', 'Boolean', 'Literal', 'Union'
 }
 
 enum EnumType {
@@ -87,6 +87,9 @@ class Compiler {
       case 'object': return RuleType.Object
       case 'string': return RuleType.String
     }
+    if (Array.isArray(rule.type)) {
+      return RuleType.Union
+    }
     if (this.isNumberLiteral(rule)) {
       return RuleType.Number
     }
@@ -238,6 +241,8 @@ class Compiler {
         return new TsType.Union(rule.anyOf!.map(_ => this.toTsType(_)))
       case RuleType.Reference:
         return this.resolveType(rule.$ref!, propName!)
+      case RuleType.Union:
+        return new TsType.Union((rule.type as any[]).map(_ => this.toTsType(_)))
     }
     throw new Error('Unknown rule:' + rule.toString())
   }

test/cases/disjoint-type.ts

@@ -0,0 +1,21 @@
+export var schema = {
+  "title": "Example Schema",
+  "description": "My cool schema",
+  "type": "object",
+  "properties": {
+    "value": {
+      "type": ["number", "string"]
+    },
+    "anotherValue": {
+      "type": ["null", "string"]
+    }
+  },
+  "required": ["value"]
+}
+
+export var types = `/** My cool schema */
+export interface ExampleSchema {
+  value: number | string;
+  anotherValue?: null | string;
+  [k: string]: any;
+}`