add object type, closes #86

CHANGELOG.md

@@ -12,6 +12,11 @@
 **Note**: Gaps between patch versions are faulty/broken releases.
 **Note**: A feature tagged as Experimental is in a high state of flux, you're at risk of it changing without notice.
 
+# 0.8.2
+
+- **New Feature**
+  - add `object` type, closes #86 (@gcanti)
+
 # 0.8.1
 
 - **New Feature**

README.md

@@ -142,6 +142,7 @@ import * as t from 'io-ts'
 | boolean | `boolean` | `t.boolean` |
 | any | `any` | `t.any` |
 | never | `never` | `t.never` |
+| object | `object` | `t.object` |
 | integer | ✘ | `t.Integer` |
 | array of any | `Array<any>` | `t.Array` |
 | array of type | `Array<A>` | `t.array(A)` |

package.json

@@ -1,6 +1,6 @@
 {
   "name": "io-ts",
-  "version": "0.8.1",
+  "version": "0.8.2",
   "description": "TypeScript compatible runtime type system for IO validation",
   "files": ["lib"],
   "main": "lib/index.js",

src/index.ts

@@ -156,6 +156,15 @@ export class AnyDictionaryType implements Type<{ [key: string]: any }> {
 
 export const Dictionary: AnyDictionaryType = new AnyDictionaryType()
 
+export class ObjectType implements Type<object> {
+  readonly _tag: 'ObjectType' = 'ObjectType'
+  readonly _A: object
+  readonly name: 'object' = 'object'
+  readonly validate: Validate<object> = Dictionary.validate
+}
+
+export const object: ObjectType = new ObjectType()
+
 export class FunctionType implements Type<Function> {
   readonly _tag: 'FunctionType' = 'FunctionType'
   readonly _A: Function

test/default-types.ts

@@ -38,3 +38,26 @@ describe('null', () => {
     assertFailure(t.validate(1, t.null), ['Invalid value 1 supplied to : null'])
   })
 })
+
+describe('object', () => {
+  it('should accept arrays', () => {
+    assertSuccess(t.validate([], t.object))
+  })
+
+  it('should accept objects', () => {
+    assertSuccess(t.validate({}, t.object))
+  })
+
+  it('should fail with primitives', () => {
+    const T = t.object
+    assertFailure(t.validate('s', T), ['Invalid value "s" supplied to : object'])
+    assertFailure(t.validate(1, T), ['Invalid value 1 supplied to : object'])
+    assertFailure(t.validate(true, T), ['Invalid value true supplied to : object'])
+  })
+
+  it('should fail with null and undefined', () => {
+    const T = t.object
+    assertFailure(t.validate(null, T), ['Invalid value null supplied to : object'])
+    assertFailure(t.validate(undefined, T), ['Invalid value undefined supplied to : object'])
+  })
+})

typings-checker/index.ts

@@ -198,3 +198,12 @@ const x33input = { name: 'foo', foo: 'foo' }
 const x33: TS1 = x33input
 // $ExpectError Argument of type 'StringType' is not assignable to parameter of type 'Props'
 const S2 = t.strict(t.string)
+
+//
+// object
+//
+const O1 = t.object
+type TO1 = TypeOf<typeof O1>
+const x34: TO1 = { name: 'Giulio' }
+// $ExpectError Type '"foo"' is not assignable to type 'object'
+const x35: TO1 = 'foo'