From b55561d55d8ee074272f154fac3a439258f2a32f Mon Sep 17 00:00:00 2001
From: antoine lanoe <antoine.lanoe@linkfluence.com>
Date: Fri, 23 Dec 2022 17:33:42 +0100
Subject: [PATCH] feat: add readme

---
 README.md | 153 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)
 create mode 100644 README.md

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+## DATA DIFF
+
+This library compares two arrays or objects and return a complete diff of their differences.
+
+# Object exemple:
+
+`getObjectDiff()` checks base properties but also provides a complete diff of nested properties.
+
+Input
+
+```js
+getObjectDiff(
+  {
+    id: 54,
+    user: {
+      name: "joe",
+      member: true,
+      hobbies: ["golf", "football"],
+      age: 66,
+    },
+  },
+  {
+    id: 54,
+    user: {
+      name: "joe",
+      member: false,
+      hobbies: ["golf", "chess"],
+      age: 66,
+    },
+  }
+);
+```
+
+Output
+
+```js
+{
+      type: "object",
+      status: "updated",
+      diff: [
+        {
+          property: "id",
+          previousValue: 54,
+          currentValue: 54,
+          status: "equal",
+        },
+        {
+          property: "user",
+          previousValue: {
+            name: "joe",
+            member: true,
+            hobbies: ["golf", "football"],
+            age: 66,
+          },
+          currentValue: {
+            name: "joe",
+            member: false,
+            hobbies: ["golf", "chess"],
+            age: 66,
+          },
+          status: "updated",
+          subPropertiesDiff: [
+            {
+              name: "name",
+              previousValue: "joe",
+              currentValue: "joe",
+              status: "equal",
+            },
+            {
+              name: "member",
+              previousValue: true,
+              currentValue: false,
+              status: "updated",
+            },
+            {
+              name: "hobbies",
+              previousValue: ["golf", "football"],
+              currentValue: ["golf", "chess"],
+              status: "updated",
+            },
+            {
+              name: "age",
+              previousValue: 66,
+              currentValue: 66,
+              status: "equal",
+            },
+          ],
+        },
+      ],
+    }
+```
+
+List exemple:
+
+`getListDiff()` works with arrays of string, number and objects.
+It doesn't work yet with duplicated values.
+
+Input
+
+```js
+getListDiff(
+  ["mbappe", "mendes", "verratti", "ruiz"],
+  ["mbappe", "messi", "ruiz"]
+);
+```
+
+Output
+
+```js
+{
+      type: "list",
+      status: "updated",
+      diff: [
+        {
+          value: "mbappe",
+          prevIndex: 0,
+          newIndex: 0,
+          indexDiff: 0,
+          status: "equal",
+        },
+        {
+          value: "mendes",
+          prevIndex: 1,
+          newIndex: null,
+          indexDiff: null,
+          status: "deleted",
+        },
+        {
+          value: "verratti",
+          prevIndex: 2,
+          newIndex: null,
+          indexDiff: null,
+          status: "deleted",
+        },
+        {
+          value: "messi",
+          prevIndex: null,
+          newIndex: 1,
+          indexDiff: null,
+          status: "added",
+        },
+        {
+          value: "ruiz",
+          prevIndex: 3,
+          newIndex: 2,
+          indexDiff: -1,
+          status: "moved",
+        },
+      ],
+    }
+```
+
+See tests for more visual examples.