{"id":28276582,"url":"https://github.com/alkemist/compare-engine","last_synced_at":"2026-05-19T10:31:52.163Z","repository":{"id":170676260,"uuid":"646883846","full_name":"alkemist/compare-engine","owner":"alkemist","description":"Json comparison 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Compare Engine\n\n## Installation\n\n* From npm: `npm install @alkemist/compare-engine`\n* From yarn: `yarn add @alkemist/compare-engine`\n\n## Test\n\n* From npm: `npm test`\n* From yarn: `yarn test`\n\n## About\n\nCompares 2 value, considering array object movement :\n\n- Either with a signature (identical object)\n- Or with a key defined by the method passed to the constructor\n- The search is recursive: if an object has been moved within a moved object, it will be detected as moved\n- Takes into consideration : value type/class, function name and signature (without parameter type)\n\n## Examples\n\n### With JSON\n\n    import {CompareEngine} from '@alkemist/compare-engine';\n\n    const jsonLeft = {\n        objectArray: [\n            {\n                id: \"movedIndex\",\n                property: \"old property\",\n                otherObjectArray: [\n                    {id: \"1\"},\n                    {id: \"2\"},\n                ],\n                otherArray: [\n                    0, 1, 2\n                ]\n            },\n            {\n                id: \"removedObject\",\n            },\n            {\n                id: \"equal\"\n            }\n        ]\n    };\n    const jsonright = {\n        objectArray: [\n            {\n                id: \"newObject\",\n            },\n            {\n                id: \"movedIndex\",\n                property: \"updated property\",\n                otherObjectArray: [\n                    {id: \"2\"},\n                    {id: \"1\"},\n                ],\n                otherArray: [\n                    2, 1, 3\n                ]\n            },\n            {\n                id: \"equal\"\n            }\n        ]\n    };\n\n    const compareEngine = new CompareEngine((paths: string[]) =\u003e {\n      return \"id\";\n    });\n\n    compareEngine.updateLeft(jsonLeft);\n    compareEngine.updateRight(jsonRight);\n\n    compareEngine.updateCompareIndex();\n\n    compareEngine.getLeftState(\"\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray[0]\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray[0].id\") // return EQUAL CompareState\n    compareEngine.getLeftState(\"objectArray[0].property\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherObjectArray\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherObjectArray[0]\") // return MOVED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherObjectArray[0].id\") // return NONE CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherObjectArray[1]\") // return MOVED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherObjectArray[1].id\") // return NONE CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherArray\") // return UPDATED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherArray[0]\") // return REMOVED CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherArray[1]\") // return EQUAL CompareState\n    compareEngine.getLeftState(\"objectArray[0].otherArray[2]\") // return MOVED CompareState\n    compareEngine.getLeftState(\"objectArray[1]\") // return REMOVED CompareState\n    compareEngine.getLeftState(\"objectArray[1].id\") // return NONE CompareState\n    compareEngine.getLeftState(\"objectArray[2]\") // return EQUAL CompareState\n    compareEngine.getLeftState(\"objectArray[2].id\") // return NONE CompareState\n\n    compareEngine.getRightState(\"\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray[0]\") // return ADDED CompareState\n    compareEngine.getRightState(\"objectArray[0].id\") // return NONE CompareState\n    compareEngine.getRightState(\"objectArray[1]\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray[1].id\") // return EQUAL CompareState\n    compareEngine.getRightState(\"objectArray[1].property\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherObjectArray\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherObjectArray[0]\") // return MOVED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherObjectArray[0].id\") // return NONE CompareState\n    compareEngine.getRightState(\"objectArray[1].otherObjectArray[1]\") // return MOVED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherObjectArray[1].id\") // return NONE CompareState\n    compareEngine.getRightState(\"objectArray[1].otherArray\") // return UPDATED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherArray[0]\") // return MOVED CompareState\n    compareEngine.getRightState(\"objectArray[1].otherArray[1]\") // return EQUAL CompareState\n    compareEngine.getRightState(\"objectArray[1].otherArray[2]\") // return ADDED CompareState\n    compareEngine.getRightState(\"objectArray[2]\") // return EQUAL CompareState\n    compareEngine.getRightState(\"objectArray[2].id\") // return NONE CompareState\n\n### With Objects\n\n    class Parent {\n        constructor(protected property = \"value\") {\n        }\n    }\n\n    class Child extends Parent {\n        constructor(protected override property = \"value\") {\n            super();\n        }\n    }\n\n    const compareEngine = new CompareEngine((paths: string[]) =\u003e {\n      return \"id\";\n    }, new Parent(), new Parent());\n    compareEngine.updateCompareIndex();\n    compareEngine.getLeftState(\"\") // return EQUAL CompareState\n\n    const compareEngine = new CompareEngine((paths: string[]) =\u003e {\n      return \"id\";\n    }, new Parent(), new Child());\n    compareEngine.updateCompareIndex();\n    compareEngine.getLeftState(\"\") // return UPDATED CompareState\n\n    const compareEngine = new CompareEngine((paths: string[]) =\u003e {\n      return \"id\";\n    }, new Child(), new Child(\"otherValue\"));\n    compareEngine.updateCompareIndex();\n    compareEngine.getLeftState(\"\") // return UPDATED CompareState\n\n## Exposed models, enums and utils\n\n    enum CompareStateEnum {\n        NONE = \"\",\n        ADDED = \"added\",\n        MOVED = \"moved\",\n        UPDATED = \"updated\",\n        REMOVED = \"removed\",\n        EQUAL = \"equal\",\n    }\n\n    class CompareEngine\u003cDATA_TYPE\u003e {\n        constructor(\n            protected determineArrayIndexFn?: (paths: ValueKey[]) =\u003e ValueKey\n            leftValue?: DATA_TYPE = null,\n            rightValue?: DATA_TYPE = null\n        )\n\n        get leftValue(): DATA_TYPE | undefined\n        get rightValue(): DATA_TYPE | undefined\n\n        getInLeft(paths: ValueKey[] | ValueKey): unknown\n        getInRight(paths: ValueKey[] | ValueKey): unknown\n\n        updateLeft(value: DATA_TYPE | undefined): void\n        updateRight(value: DATA_TYPE | undefined): void\n\n        updateInLeft(value: DATA_TYPE | undefined, paths: ValueKey[] | ValueKey): void\n        updateInRight(value: DATA_TYPE | undefined, paths: ValueKey[] | ValueKey): void\n\n        leftToRight(): void\n        rightToLeft(): void\n\n        updateCompareIndex(): void\n\n        hasChange(): boolean\n\n        getLeftState(paths: ValueKey[] | ValueKey): CompareState\n        getRightState(paths: ValueKey[] | ValueKey): CompareState\n    }\n\n    class CompareState {\n        value: CompareStateEnum\n\n        isNone(): boolean\n        isAdded(): boolean\n        isMoved(): boolean\n        isUpdated(): boolean\n        isRemoved(): boolean\n        isEqual(): boolean\n        isChanged(): boolean\n\n        toString(): string\n    }\n\n## License\n\n[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0.html)","project_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Falkemist%2Fcompare-engine","html_url":"https://awesome.ecosyste.ms/projects/github.com%2Falkemist%2Fcompare-engine","lists_url":"https://awesome.ecosyste.ms/api/v1/projects/github.com%2Falkemist%2Fcompare-engine/lists"}