From 7c838f59b487a039585573e6bcb506dd3ef7c283 Mon Sep 17 00:00:00 2001
From: DoneDeal0 <ap.lanoe@outlook.com>
Date: Sat, 24 Dec 2022 13:47:34 +0100
Subject: [PATCH] feat: detect add/removal of main properties

---
 src/object-diff.ts       | 42 ++++++++++++++++++++++++++++++++++++----
 test/object-diff.test.ts | 14 ++++++++++++++
 2 files changed, 52 insertions(+), 4 deletions(-)

diff --git a/src/object-diff.ts b/src/object-diff.ts
index 64e88de..f2d2b82 100644
--- a/src/object-diff.ts
+++ b/src/object-diff.ts
@@ -84,11 +84,27 @@ function getPropertyStatus(subPropertiesDiff: Subproperties[]): DiffStatus {
     : STATUS.EQUAL;
 }
 
-function getDeletedProperties(
+function getDeletedMainProperties(
+  previousValue: Record<string, any>,
+  nextValue: Record<string, any>
+): { property: string; value: any }[] | undefined {
+  const prevKeys = Object.keys(previousValue);
+  const nextKeys = Object.keys(nextValue);
+  const deletedKeys = prevKeys.filter((prevKey) => !nextKeys.includes(prevKey));
+  if (deletedKeys.length > 0) {
+    return deletedKeys.map((deletedKey) => ({
+      property: deletedKey,
+      value: previousValue[deletedKey],
+    }));
+  }
+  return undefined;
+}
+
+function getDeletedSubProperties(
   previousValue: any,
   nextValue: any,
   nextProperty: string
-) {
+): { property: string; value: any }[] | undefined {
   if (!previousValue) return undefined;
   const previousMatch = previousValue[nextProperty];
   if (!previousMatch) return undefined;
@@ -130,7 +146,7 @@ function getSubPropertiesDiff(
       if (data && data.length > 0) {
         subDiff = data;
       }
-      const deletedProperties = getDeletedProperties(
+      const deletedProperties = getDeletedSubProperties(
         previousValue,
         nextValue,
         nextSubProperty
@@ -184,7 +200,14 @@ export function getObjectDiff(
   const diff: ObjectDiff["diff"] = [];
   Object.entries(nextData).forEach(([nextProperty, nextValue]) => {
     const previousValue = prevData[nextProperty];
-
+    if (!!!previousValue) {
+      return diff.push({
+        property: nextProperty,
+        previousValue: undefined,
+        currentValue: nextValue,
+        status: STATUS.ADDED,
+      });
+    }
     if (isObject(nextValue)) {
       const subPropertiesDiff: Subproperties[] = getSubPropertiesDiff(
         previousValue,
@@ -205,6 +228,17 @@ export function getObjectDiff(
       status: getValueStatus(previousValue, nextValue),
     });
   });
+  const deletedProperties = getDeletedMainProperties(prevData, nextData);
+  if (deletedProperties) {
+    deletedProperties.forEach((deletedProperty) => {
+      diff.push({
+        property: deletedProperty.property,
+        previousValue: deletedProperty.value,
+        currentValue: undefined,
+        status: STATUS.DELETED,
+      });
+    });
+  }
   return {
     type: "object",
     status: getObjectStatus(diff),
diff --git a/test/object-diff.test.ts b/test/object-diff.test.ts
index 48cfe25..1797485 100644
--- a/test/object-diff.test.ts
+++ b/test/object-diff.test.ts
@@ -76,6 +76,7 @@ describe("getObjectDiff", () => {
       getObjectDiff(
         {
           id: 54,
+          type: "sport",
           user: {
             name: "joe",
             member: true,
@@ -85,6 +86,7 @@ describe("getObjectDiff", () => {
         },
         {
           id: 54,
+          country: "us",
           user: {
             name: "joe",
             member: false,
@@ -103,6 +105,12 @@ describe("getObjectDiff", () => {
           currentValue: 54,
           status: "equal",
         },
+        {
+          property: "country",
+          previousValue: undefined,
+          currentValue: "us",
+          status: "added",
+        },
         {
           property: "user",
           previousValue: {
@@ -145,6 +153,12 @@ describe("getObjectDiff", () => {
             },
           ],
         },
+        {
+          property: "type",
+          previousValue: "sport",
+          currentValue: undefined,
+          status: "deleted",
+        },
       ],
     });
   });