{"version":3,"file":"merge-records.mjs","sources":["../../src/record/merge-records.mts"],"sourcesContent":["import { Arr, expectType, Obj } from 'ts-data-forge';\nimport {\n type Intersection,\n type NonEmptyTuple,\n type UnknownRecord,\n} from 'ts-type-forge';\nimport { union } from '../compose/index.mjs';\nimport { literal } from '../other-types/index.mjs';\nimport {\n type ExcessPropertyOption,\n type RecordTypeInternals,\n type Type,\n type TypeOf,\n expandShapeStructure,\n hasRecordInternals,\n} from '../type.mjs';\nimport { toIntersectionString } from '../utils/index.mjs';\nimport { record } from './record.mjs';\n\nconst MERGE_RECORDS_MAX_VARIANTS = 10_000;\n\nexport const mergeRecords = <\n const Types extends NonEmptyTuple>,\n>(\n recordTypes: Types,\n options?: Partial<\n Readonly<{\n typeName: string;\n excessProperty: ExcessPropertyOption;\n }>\n >,\n): MergeRecordsType => {\n if (!recordTypes.every(hasRecordInternals)) {\n throw new Error(\n 'Expected a record type but received a non-record type in mergeRecords',\n );\n }\n\n const typeNameFilled: string =\n options?.typeName ??\n `(${toIntersectionString(recordTypes.map((a) => a.typeName))})`;\n\n // Expand all shape structures to get all possible shape combinations\n const expandedShapesPerType = Arr.map(recordTypes, (t) =>\n expandShapeStructure(t.shapeStructure),\n );\n\n // Estimate the total number of merged variants that would be produced.\n // This is the product of the number of variants for each record type.\n const estimatedVariantCount = expandedShapesPerType.reduce(\n (acc, shapes) => acc * shapes.length,\n 1,\n );\n\n if (estimatedVariantCount > MERGE_RECORDS_MAX_VARIANTS) {\n throw new Error(\n `mergeRecords would create ${estimatedVariantCount} record variants, exceeding the limit of ${MERGE_RECORDS_MAX_VARIANTS}. ` +\n 'This could lead to excessive memory or CPU usage. Consider simplifying the record types or reducing union/intersection nesting.',\n );\n }\n\n // For merging records (which is an intersection operation),\n // we need to create the cartesian product of all variants\n // For example: {a} & ({b} | {c}) = ({a} & {b}) | ({a} & {c})\n const allCombinations = Arr.cartesianProduct(expandedShapesPerType);\n\n // Merge each combination\n const mergedShapes = Arr.map(allCombinations, (shapes) =>\n Obj.merge(...shapes),\n );\n\n const excessProperty =\n options?.excessProperty ?? deriveStrictestExcessProperty(recordTypes);\n\n // If there's only one merged shape, return it directly\n if (Arr.isFixedLengthTuple(mergedShapes, 1)) {\n // eslint-disable-next-line total-functions/no-unsafe-type-assertion\n return record(mergedShapes[0], {\n typeName: typeNameFilled,\n excessProperty,\n }) as MergeRecordsType;\n }\n\n // If there are multiple variants, we need to return a union\n const variants = Arr.map(mergedShapes, (shape) =>\n record(shape, { excessProperty }),\n );\n\n // eslint-disable-next-line total-functions/no-unsafe-type-assertion\n return union(variants as NonEmptyTuple>, {\n typeName: typeNameFilled,\n }) as MergeRecordsType;\n};\n\ntype MergeRecordsType[]> = Type<\n MergedExactValue\n>;\n\n/** Compute the merged value type directly from input types' `defaultValue`. */\ntype MergedExactValue[]> =\n FlattenIntersection>>;\n\n/** Flatten an intersection result into a single mapped type for better TypeScript compatibility. */\ntype FlattenIntersection = T extends UnknownRecord\n ? Readonly<{ [K in keyof T]: T[K] }>\n : T;\n\ntype ExactValueTuple =\n Types extends readonly [infer Head, ...infer Tail]\n ? readonly [ExactValueOf, ...ExactValueTuple]\n : readonly [];\n\ntype ExactValueOf =\n T extends Readonly<{ defaultValue: infer V }> ? V : never;\n\nconst deriveStrictestExcessProperty = (\n types: readonly RecordTypeInternals[],\n): ExcessPropertyOption =>\n types.some((t) => t.excessProperty === 'reject') ? 'reject' : 'allow';\n\n// Verify MergedExactValue flattens correctly\n{\n type R1 = ReturnType<\n typeof record; y: Type }>>\n >;\n\n type R2 = ReturnType<\n typeof record; w: Type }>>\n >;\n\n expectType<\n MergedExactValue,\n Readonly<{ x: number; y: number; z: number; w: number }>\n >('=');\n}\n\nexpectType<\n TypeOf<\n Type<\n Readonly<{\n a: 0;\n b: 0;\n }>\n >\n >,\n Readonly<{\n a: 0;\n b: 0;\n }>\n>('=');\n\nexpectType<\n Intersection<\n readonly [\n Readonly<{\n a: 0;\n b: 0;\n }>,\n Readonly<{\n b: 0;\n c: 0;\n }>,\n ]\n >,\n Readonly<{\n a: 0;\n b: 0;\n c: 0;\n }>\n>('=');\n\nexpectType<\n Intersection<\n readonly [\n Readonly<{\n a: 0;\n b: 0;\n }>,\n Readonly<{\n b: 0;\n c: 0;\n }>,\n Readonly<{\n c: 0;\n d: 0;\n }>,\n ]\n >,\n Readonly<{\n a: 0;\n b: 0;\n c: 0;\n d: 0;\n }>\n>('=');\n\nexpectType<\n Intersection<\n readonly [\n Readonly<{\n a: 0;\n b: 0;\n }>,\n Readonly<{\n b: 1;\n c: 0;\n }>,\n ]\n >,\n never\n>('=');\n\nif (import.meta.vitest !== undefined) {\n test('Obj.merge for shapes', () => {\n const _m1 = Obj.merge(\n { a: literal(0), b: literal(0) },\n { c: literal(0), d: literal(0) },\n );\n\n expectType<\n typeof _m1,\n Readonly<{\n a: Type<0>;\n b: Type<0>;\n c: Type<0>;\n d: Type<0>;\n }>\n >('=');\n\n const _m2 = Obj.merge(\n { a: literal(0), b: literal(0) },\n { b: literal(0), c: literal(0) },\n );\n\n expectType<\n typeof _m2,\n Readonly<{\n a: Type<0>;\n b: Type<0>;\n c: Type<0>;\n }>\n >('=');\n\n assert.isTrue(true); // dummy assertion to avoid \"Test has no assertions\" error\n });\n}\n"],"names":[],"mappings":";;;;;;;;AAmBA,MAAM,0BAAA,GAA6B,GAAA;MAEtB,YAAA,GAAe,CAG1B,WAAA,EACA,OAAA,KAM4B;AAC5B,EAAA,IAAI,CAAC,WAAA,CAAY,KAAA,CAAM,kBAAkB,CAAA,EAAG;AAC1C,IAAA,MAAM,IAAI,KAAA;AAAA,MACR;AAAA,KACF;AAAA,EAAA;AAGF,EAAA,MAAM,cAAA,GACJ,OAAA,EAAS,QAAA,IACT,CAAA,CAAA,EAAI,oBAAA,CAAqB,WAAA,CAAY,GAAA,CAAI,CAAC,CAAA,KAAM,CAAA,CAAE,QAAQ,CAAC,CAAC,CAAA,CAAA,CAAA;AAG9D,EAAA,MAAM,wBAAwB,GAAA,CAAI,GAAA;AAAA,IAAI,WAAA;AAAA,IAAa,CAAC,CAAA,KAClD,oBAAA,CAAqB,CAAA,CAAE,cAAc;AAAA,GACvC;AAIA,EAAA,MAAM,wBAAwB,qBAAA,CAAsB,MAAA;AAAA,IAClD,CAAC,GAAA,EAAK,MAAA,KAAW,GAAA,GAAM,MAAA,CAAO,MAAA;AAAA,IAC9B;AAAA,GACF;AAEA,EAAA,IAAI,wBAAwB,0BAAA,EAA4B;AACtD,IAAA,MAAM,IAAI,KAAA;AAAA,MACR,CAAA,0BAAA,EAA6B,qBAAqB,CAAA,yCAAA,EAA4C,0BAA0B,CAAA,iIAAA;AAAA,KAE1H;AAAA,EAAA;AAMF,EAAA,MAAM,eAAA,GAAkB,GAAA,CAAI,gBAAA,CAAiB,qBAAqB,CAAA;AAGlE,EAAA,MAAM,eAAe,GAAA,CAAI,GAAA;AAAA,IAAI,eAAA;AAAA,IAAiB,CAAC,MAAA,KAC7C,GAAA,CAAI,KAAA,CAAM,GAAG,MAAM;AAAA,GACrB;AAEA,EAAA,MAAM,cAAA,GACJ,OAAA,EAAS,cAAA,IAAkB,6BAAA,CAA8B,WAAW,CAAA;AAGtE,EAAA,IAAI,GAAA,CAAI,kBAAA,CAAmB,YAAA,EAAc,CAAC,CAAA,EAAG;AAE3C,IAAA,OAAO,MAAA,CAAO,YAAA,CAAa,CAAC,CAAA,EAAG;AAAA,MAC7B,QAAA,EAAU,cAAA;AAAA,MACV;AAAA,KACD,CAAA;AAAA,EAAA;AAIH,EAAA,MAAM,WAAW,GAAA,CAAI,GAAA;AAAA,IAAI,YAAA;AAAA,IAAc,CAAC,KAAA,KACtC,MAAA,CAAO,KAAA,EAAO,EAAE,gBAAgB;AAAA,GAClC;AAGA,EAAA,OAAO,MAAM,QAAA,EAAgD;AAAA,IAC3D,QAAA,EAAU;AAAA,GACX,CAAA;AACH;AAuBA,MAAM,6BAAA,GAAgC,CACpC,KAAA,KAEA,KAAA,CAAM,IAAA,CAAK,CAAC,CAAA,KAAM,CAAA,CAAE,cAAA,KAAmB,QAAQ,CAAA,GAAI,QAAA,GAAW,OAAA;;;;"}