Merge pull request #12 from marquesVF/fix/build-object-transformation…

…-when-property-is-undefined

Fix/build object transformation when property is undefined

lib/build-object.ts

@@ -41,11 +41,13 @@ export function buildObject<T>(
                 throw new Error(`Property ${objPropName} type is not assignable to ${expectedType}. Found ${value}`)
             }
 
-            const transformMetadata = transformations
-                ?.find(metadata => metadata.propertyKey === propertyKey)
-            if (transformMetadata) {
-                // TODO improve error handling since it may raise errors in runtine
-                value = transformMetadata.transformer.transform(value)
+            if (value !== undefined) {
+                const transformMetadata = transformations
+                    ?.find(metadata => metadata.propertyKey === propertyKey)
+                if (transformMetadata) {
+                    // TODO improve error handling since it may raise errors in runtine
+                    value = transformMetadata.transformer.transform(value)
+                }
             }
 
             if (type && !nullable) {

lib/types/transformation.ts

@@ -1,4 +1,4 @@
-export type BuildTransformationFn<T> = (value: unknown) => T
+export type BuildTransformationFn<T> = (value: any) => T
 
 export interface BuildTransformer<T> {
     transform: BuildTransformationFn<T>

package.json

@@ -1,6 +1,6 @@
 {
   "name": "objectypes",
-  "version": "1.1.4",
+  "version": "1.1.5",
   "description": "A type-safe library to transform and validate objects",
   "files": [
     "dist"

test/fixtures/optional-build-model.ts

@@ -0,0 +1,11 @@
+import { Property, BuildTransformation } from '../../lib'
+
+export class OptionalBuildModel {
+
+    @BuildTransformation({
+        transform: (value: string) => value.replace(/\./g, '')
+    })
+    @Property({ nullable: true })
+    code?: string
+
+}

test/lib/property-transformation.spec.ts

@@ -1,5 +1,6 @@
 import { Transformable } from '../fixtures/transformable'
 import { extractObject, buildObject } from '../../lib'
+import { OptionalBuildModel } from '../fixtures/optional-build-model'
 
 describe('property transformation', () => {
     const extractedObject = {
@@ -45,5 +46,13 @@ describe('property transformation', () => {
                 expect(result).toThrowError()
             })
         })
+
+        describe('when typed object has a transformation for a optional property', () => {
+            it('should not execute the transformation if property is undefined', () => {
+                const builder = () => buildObject(OptionalBuildModel, { })
+
+                expect(builder).not.toThrowError()
+            })
+        })
     })
 })

test/lib/validate-object.spec.ts

@@ -3,6 +3,7 @@ import { NestedModel } from '../fixtures/nested-model'
 import { validateObject } from '../../lib'
 import { VendorModel } from '../fixtures/vendor-model'
 import { ComplexModel } from '../fixtures/complex-mode'
+import { PrimitiveModel } from '../fixtures/primitive-model'
 
 describe('validateObject method', () => {
     describe('when there is a valid JSON object', () => {
@@ -95,4 +96,19 @@ describe('validateObject method', () => {
             expect(typeErrors).toHaveLength(0)
         })
     })
+
+    describe('when model has primitive types', () => {
+        describe('when json object has unexpected property types but convertable', () => {
+            const model = {
+                counter: '10',
+                createdAt: '2020-08-14T17:34:42.475Z'
+            }
+
+            it('should not return any type error', () => {
+                const { typeErrors } = validateObject(PrimitiveModel, model)
+
+                expect(typeErrors).toHaveLength(0)
+            })
+        })
+    })
 })