Merge pull request #10 from marcolink/feat/max-depth

feat: add max depth config

Author: marcolink

src/index.spec.ts

@@ -653,6 +653,44 @@ describe('a generate json patch function', () => {
       ]);
     });
   });
+
+  describe('with maxDepth config', () => {
+    const before = {
+      firstLevel: {
+        secondLevel: {
+          thirdLevel: {
+            fourthLevel: 'hello-world',
+          },
+          thirdLevelTwo: 'hello',
+        },
+      },
+    };
+
+    const after = {
+      firstLevel: {
+        secondLevel: {
+          thirdLevel: {
+            fourthLevel: 'hello-brave-new-world',
+          },
+          thirdLevelTwo: 'hello',
+        },
+      },
+    };
+
+    const patch = generateJSONPatch(before, after, { maxDepth: 3 });
+    expect(patch).to.eql([
+      {
+        op: 'replace',
+        path: '/firstLevel/secondLevel',
+        value: {
+          thirdLevel: {
+            fourthLevel: 'hello-brave-new-world',
+          },
+          thirdLevelTwo: 'hello',
+        },
+      },
+    ]);
+  });
 });
 
 function doPatch(json: JsonValue, patch: Patch) {

src/index.ts

@@ -71,6 +71,7 @@ export type JsonPatchConfig = {
   objectHash?: ObjectHash;
   propertyFilter?: PropertyFilter;
   array?: { ignoreMove?: boolean };
+  maxDepth?: number;
 };
 
 export const defaultObjectHash: ObjectHash = (obj, context) => {
@@ -82,7 +83,11 @@ export function generateJSONPatch(
   after: JsonValue,
   config: JsonPatchConfig = {}
 ): Patch {
-  const { objectHash = defaultObjectHash, propertyFilter } = config;
+  const {
+    objectHash = defaultObjectHash,
+    propertyFilter,
+    maxDepth = Infinity,
+  } = config;
   const patch: Patch = [];
   const hasPropertyFilter = typeof propertyFilter === 'function';
 
@@ -181,7 +186,11 @@ export function generateJSONPatch(
         compareArrays(leftValue, rightValue, newPath);
       } else if (isJsonObject(rightValue)) {
         if (isJsonObject(leftValue)) {
-          compareObjects(newPath, leftValue, rightValue);
+          if (maxDepth <= path.split('/').length) {
+            patch.push({ op: 'replace', path: path, value: rightJsonValue });
+          } else {
+            compareObjects(newPath, leftValue, rightValue);
+          }
         } else if (leftJsonValue.hasOwnProperty(rightKey)) {
           patch.push({ op: 'replace', path: newPath, value: rightValue });
         } else {