Merge pull request #961 from streamich/improve-json-patch-diff

Improve JSON Patch diff

Author: streamich

packages/json-joy/src/index.ts

@@ -12,4 +12,3 @@ export type * from './json-crdt';
 export type * from './json-crdt-patch';
 export type * from './json-crdt-extensions';
 export type * from './json-patch/types';
-export type * from '../../json-path/src/types';

packages/json-joy/src/json-patch-diff/JsonPatchDiff.ts

@@ -2,6 +2,7 @@ import {deepEqual} from '@jsonjoy.com/util/lib/json-equal/deepEqual';
 import * as str from '../util/diff/str';
 import * as line from '../util/diff/line';
 import {structHash} from '../json-hash';
+import {escapeComponent} from '@jsonjoy.com/json-pointer/lib/util';
 import type {Operation} from '../json-patch/codec/json/types';
 
 export class JsonPatchDiff {
@@ -34,14 +35,14 @@ export class JsonPatchDiff {
         const val1 = src[key];
         const val2 = dst[key];
         if (val1 === val2) continue;
-        this.diffAny(path + '/' + key, val1, val2);
+        this.diffAny(path + '/' + escapeComponent(key), val1, val2);
       } else {
-        patch.push({op: 'remove', path: path + '/' + key});
+        patch.push({op: 'remove', path: path + '/' + escapeComponent(key)});
       }
     }
     for (const key in dst) {
       if (key in src) continue;
-      patch.push({op: 'add', path: path + '/' + key, value: dst[key]});
+      patch.push({op: 'add', path: path + '/' + escapeComponent(key), value: dst[key]});
     }
   }
 
@@ -78,6 +79,16 @@ export class JsonPatchDiff {
   }
 
   public diffAny(path: string, src: unknown, dst: unknown): void {
+    // Check for type changes first
+    const srcType = Array.isArray(src) ? 'array' : typeof src;
+    const dstType = Array.isArray(dst) ? 'array' : typeof dst;
+
+    if (srcType !== dstType) {
+      // Different types, replace entirely
+      this.diffVal(path, src, dst);
+      return;
+    }
+
     switch (typeof src) {
       case 'string': {
         if (typeof dst === 'string') this.diffStr(path, src, dst);