From 08a17a9c301731efa2f4eb8a4309bc31fcbeede7 Mon Sep 17 00:00:00 2001
From: martynv <m@rtyn.io>
Date: Fri, 2 Apr 2021 12:07:24 +0200
Subject: [PATCH] Adds object/toKeyValuePairs

Adds a pipe that transforms objects to an array of key-value pairs.
---
 README.md                             |  1 +
 docs/object.md                        | 26 +++++++++++++++++++++++++
 src/object/object.module.ts           |  6 ++++--
 src/object/to-key-value-pairs.spec.ts | 25 ++++++++++++++++++++++++
 src/object/to-key-value-pairs.ts      | 28 +++++++++++++++++++++++++++
 src/public_api.ts                     |  1 +
 6 files changed, 85 insertions(+), 2 deletions(-)
 create mode 100644 src/object/to-key-value-pairs.spec.ts
 create mode 100644 src/object/to-key-value-pairs.ts

diff --git a/README.md b/README.md
index 0bdfab0..45a099d 100644
--- a/README.md
+++ b/README.md
@@ -126,6 +126,7 @@ You can find the documentations in the [`docs`](./docs) folder or on [`GitBook`]
 - [`keys`](./docs/object.md#keys)
 - [`toArray`](./docs/object.md#toarray)
 - [`defaults`](./docs/object.md#defaults)
+- [`toKeyValuePairs`](./docs/object.md#tokeyvaluepairs)
 
 ## Install
 
diff --git a/docs/object.md b/docs/object.md
index e9e4d62..b1e62c3 100644
--- a/docs/object.md
+++ b/docs/object.md
@@ -3,6 +3,7 @@
 - [`keys`](#keys)
 - [`toArray`](#toarray)
 - [`defaults`](#defaults)
+- [`toKeyValuePairs`](#tokeyvaluepairs)
 
 You can check the module import [`here`](./modules.md).
 
@@ -93,3 +94,28 @@ const array = [{ a: 2 }, null, { b: 3 }, undefined];
 {{ array | defaults: d }}
 <!-- [{ a: 2, b: 2, c: 3 }, { a: 1, b: 2, c: 3 }, { a: 1, b: 3, c: 3 }, { a: 1, b: 2, c: 3 }]-->
 ```
+
+#### toKeyValuePairs
+
+Transforms an object to an array of key-value pairs.
+
+##### File
+
+```typescript
+import { NgToKeyValuePairsModule } from 'angular-pipes';
+```
+
+##### Usage
+
+```javascript
+const value = {
+  a: 1,
+  b: 2,
+  c: 3,
+};
+```
+
+```html
+{{ object | toKeyValuePairs }}
+<!-- [{key: 'a', value: 1}, {key: 'b', value: 2}, {key: 'c', value: 3}] -->
+```
diff --git a/src/object/object.module.ts b/src/object/object.module.ts
index 243e66a..a0c2e94 100644
--- a/src/object/object.module.ts
+++ b/src/object/object.module.ts
@@ -3,8 +3,10 @@ import { NgModule } from '@angular/core';
 import { NgKeysPipeModule } from './keys.pipe';
 import { NgToArrayPipeModule } from './to-array.pipe';
 import { NgDefaultsPipeModule } from './defaults.pipe';
+import { NgToKeyValuePairsPipeModule } from './to-key-value-pairs';
 
 @NgModule({
-  imports: [NgKeysPipeModule, NgToArrayPipeModule, NgDefaultsPipeModule],
+  imports: [NgKeysPipeModule, NgToArrayPipeModule, NgDefaultsPipeModule, NgToKeyValuePairsPipeModule],
 })
-export class NgObjectPipesModule {}
+export class NgObjectPipesModule {
+}
diff --git a/src/object/to-key-value-pairs.spec.ts b/src/object/to-key-value-pairs.spec.ts
new file mode 100644
index 0000000..3adb387
--- /dev/null
+++ b/src/object/to-key-value-pairs.spec.ts
@@ -0,0 +1,25 @@
+import { ToKeyValuePairsPipe } from './to-key-value-pairs';
+
+describe('ToKeyValuePairsPipe', () => {
+  let pipe: ToKeyValuePairsPipe;
+
+  beforeEach(() => {
+    pipe = new ToKeyValuePairsPipe();
+  });
+
+  const value = {
+    a: 1,
+    b: 2,
+    c: 3,
+  };
+
+  it('should transform the object to an array of KVPs', () => {
+    expect(pipe.transform(value)).toEqual([
+      { key: 'a', value: 1 }, { key: 'b', value: 2 }, { key: 'c', value: 3 },
+    ]);
+  });
+
+  it('should return non-object input unchanged', () => {
+    expect(pipe.transform('input')).toEqual('input');
+  });
+});
diff --git a/src/object/to-key-value-pairs.ts b/src/object/to-key-value-pairs.ts
new file mode 100644
index 0000000..2fef888
--- /dev/null
+++ b/src/object/to-key-value-pairs.ts
@@ -0,0 +1,28 @@
+import { NgModule, Pipe, PipeTransform } from '@angular/core';
+import { isObject } from '../utils/utils';
+
+/**
+ * @description Transforms an object to an array of key/value pairs,
+ * returns the input unchanged when not of type object.
+ */
+@Pipe({ name: 'toKeyValuePairs' })
+export class ToKeyValuePairsPipe implements PipeTransform {
+  transform(input: any): any {
+
+    // Any input not of type object is returned un-mutated.
+    if (!isObject(input)) {
+      return input;
+    }
+
+    // Get the array of key/values of the object and transform into an array of KVPs
+    return Object.entries(input).map(element => ({ key: element[0], value: element[1] }));
+  }
+
+}
+
+@NgModule({
+  declarations: [ToKeyValuePairsPipe],
+  exports: [ToKeyValuePairsPipe],
+})
+export class NgToKeyValuePairsPipeModule {
+}
diff --git a/src/public_api.ts b/src/public_api.ts
index b89885e..38cb797 100644
--- a/src/public_api.ts
+++ b/src/public_api.ts
@@ -74,6 +74,7 @@ export * from './math/ordinal.pipe';
 export * from './object/keys.pipe';
 export * from './object/to-array.pipe';
 export * from './object/defaults.pipe';
+export * from './object/to-key-value-pairs';
 
 export * from './string/left-pad.pipe';
 export * from './string/match.pipe';