JezK
Edit File: index.mjs
/* const obj1 = {a: 4, b: 5}; const obj2 = {a: 3, b: 5}; const obj3 = {a: 4, c: 5}; diff(obj1, obj2); [ { "op": "replace", "path": ['a'], "value": 3 } ] diff(obj2, obj3); [ { "op": "remove", "path": ['b'] }, { "op": "replace", "path": ['a'], "value": 4 } { "op": "add", "path": ['c'], "value": 5 } ] // using converter to generate jsPatch standard paths // see http://jsonpatch.com import {diff, jsonPatchPathConverter} from 'just-diff' diff(obj1, obj2, jsonPatchPathConverter); [ { "op": "replace", "path": '/a', "value": 3 } ] diff(obj2, obj3, jsonPatchPathConverter); [ { "op": "remove", "path": '/b' }, { "op": "replace", "path": '/a', "value": 4 } { "op": "add", "path": '/c', "value": 5 } ] // arrays const obj4 = {a: 4, b: [1, 2, 3]}; const obj5 = {a: 3, b: [1, 2, 4]}; const obj6 = {a: 3, b: [1, 2, 4, 5]}; diff(obj4, obj5); [ { "op": "replace", "path": ['a'], "value": 3 } { "op": "replace", "path": ['b', 2], "value": 4 } ] diff(obj5, obj6); [ { "op": "add", "path": ['b', 3], "value": 5 } ] // nested paths const obj7 = {a: 4, b: {c: 3}}; const obj8 = {a: 4, b: {c: 4}}; const obj9 = {a: 5, b: {d: 4}}; diff(obj7, obj8); [ { "op": "replace", "path": ['b', 'c'], "value": 4 } ] diff(obj8, obj9); [ { "op": "replace", "path": ['a'], "value": 5 } { "op": "remove", "path": ['b', 'c']} { "op": "add", "path": ['b', 'd'], "value": 4 } ] */ function diff(obj1, obj2, pathConverter) { if (!obj1 || typeof obj1 != 'object' || !obj2 || typeof obj2 != 'object') { throw new Error('both arguments must be objects or arrays'); } pathConverter || (pathConverter = function(arr) { return arr; }); function getDiff(obj1, obj2, basePath, diffs) { var obj1Keys = Object.keys(obj1); var obj1KeysLength = obj1Keys.length; var obj2Keys = Object.keys(obj2); var obj2KeysLength = obj2Keys.length; var path; for (var i = 0; i < obj1KeysLength; i++) { var key = Array.isArray(obj1) ? Number(obj1Keys[i]) : obj1Keys[i]; if (!(key in obj2)) { path = basePath.concat(key); diffs.remove.push({ op: 'remove', path: pathConverter(path), }); } } for (var i = 0; i < obj2KeysLength; i++) { var key = Array.isArray(obj2) ? Number(obj2Keys[i]) : obj2Keys[i]; var obj1AtKey = obj1[key]; var obj2AtKey = obj2[key]; if (!(key in obj1)) { path = basePath.concat(key); var obj2Value = obj2[key]; diffs.add.push({ op: 'add', path: pathConverter(path), value: obj2Value, }); } else if (obj1AtKey !== obj2AtKey) { if ( Object(obj1AtKey) !== obj1AtKey || Object(obj2AtKey) !== obj2AtKey ) { path = pushReplace(path, basePath, key, diffs, pathConverter, obj2); } else { if ( !Object.keys(obj1AtKey).length && !Object.keys(obj2AtKey).length && String(obj1AtKey) != String(obj2AtKey) ) { path = pushReplace(path, basePath, key, diffs, pathConverter, obj2); } else { getDiff(obj1[key], obj2[key], basePath.concat(key), diffs); } } } } return diffs; } const finalDiffs = getDiff(obj1, obj2, [], {remove: [], replace: [], add: []}); return finalDiffs.remove .reverse() .concat(finalDiffs.replace) .concat(finalDiffs.add); } function pushReplace(path, basePath, key, diffs, pathConverter, obj2) { path = basePath.concat(key); diffs.replace.push({ op: 'replace', path: pathConverter(path), value: obj2[key], }); return path; } function jsonPatchPathConverter(arrayPath) { return [''].concat(arrayPath).join('/'); } export {diff, jsonPatchPathConverter};