v5.1.0

New types

• TupleOf (#1247) 7fb2f75
• Xor (#1254) ad04bc5
• SplitOnRestElement (#1166) 34b8fad
• ExtractRestElement (#1166) 34b8fad
• ExcludeRestElement (#1166) 34b8fad

Improvements

• ReadonlyTuple: Deprecate in favor of TupleOf (#1256) af4bebc
• TsConfigJson: Add missing lib enum values (#1263) 72f491f
• TsConfigJson: Add rewriteRelativeImportExtensions (#1262) 7d011ce

Fixes

• PartialDeep: Fix behavior with functions containing multiple call signatures (#1259) 3bd9de6
• IsEqual: Fix behaviour when instantiated with never and unknown (#1251) 785549f
• FixedLengthArray: Fix element type (#1246) ee29ef7
• is-equal: Fix handling with intersecting wrapped types (#1231) 5af60a1

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v5.0.1...v5.1.0

v5.0.1

• Add missing exports 4f9c248

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v5.0.0...v5.0.1

v5.0.0

Breaking

• This package is now pure ESM. Please read this.
• Require TypeScript 5.9 b5b0214
• Require Node.js 20 cc2b0f2
• Reminder: type-fest requires strict: true in your tsconfig.
• StringKeyOf: Rename to KeyAsString e492c9c
• ArrayTail: Enable preserveReadonly by default and remove the option b34b1d8
• CamelCase / CamelCasedProperties / CamelCasedPropertiesDeep / PascalCase / PascalCasedProperties / PascalCasedPropertiesDeep: Disable preserveConsecutiveUppercase by default 8226c1b
  • This aligns it with the general JavaScript naming convention.
• PartialDeep: Disable allowUndefinedInNonTupleArrays by default b3c4524
• Split: Enable strictLiteralChecks by default 544a846
• Paths: Default maxRecursionDepth 5 (was 10) 2ab5dec
• ObservableLike: Move to sub-export 2a1072e
• Deprecate If* types in favor of a single If 4c2151a

New types

• Alphanumeric — Single alphanumeric character (A–Z, a–z, 0–9). 484e030
• AllExtend — Evaluates to true if every element of a tuple/array extends U. c8c6d55
• ConditionalSimplify — Simplifies a type’s unions/intersections with opt-in controls. b7a4771
• ConditionalSimplifyDeep — Deep version of ConditionalSimplify that recurses into objects. b7a4771
• DigitCharacter — Single ASCII digit character (0–9). 484e030
• ExcludeStrict — Non-distributive, stricter variant of Exclude<T, U>. e6f62a2
• ExtendsStrict — Non-distributive A extends B check. d71242a
• ExtractStrict — Non-distributive, stricter variant of Extract<T, U>. 98d24fa
• IsLowercase — Evaluates to true if a string literal is all lowercase. afe132c
• IsNullable — Evaluates to true if T includes null. 5067e25
• IsOptional — Evaluates to true if T includes undefined. 5067e25
• IsOptionalKeyOf — Evaluates to true if property K of T is optional. 93728b5
• IsReadonlyKeyOf — Evaluates to true if property K of T is readonly. 93728b5
• IsRequiredKeyOf — Evaluates to true if property K of T is required. 93728b5
• IsUnion — Evaluates to true if T is a union type. b3d92ed
• IsUndefined — Evaluates to true if the type is exactly undefined. f7bc576
• IsUppercase — Evaluates to true if a string literal is all uppercase. afe132c
• LowercaseLetter — Single lowercase Latin letter (a–z). 484e030
• RemovePrefix — Removes a specified prefix from a string literal. 18a1c04
• UppercaseLetter — Single uppercase Latin letter (A–Z). 484e030

Improvements

• Jsonify: Handle unknown as JsonValue 642bb13
• SetRequired / SetOptional / SetReadonly: Handle functions with properties a5e45d4
• Schema: Preserve arrays/remove extraneous unions 8a96def; drop undefined for recurseIntoArrays 1cb955b
• ReadonlyKeysOf / WritableKeysOf: Add object constraint a6efbe0
• TsConfigJson: Add TypeScript 5.9 fields d2bda94

Fixes

• Or: Fix with boolean, never, any 42d6106
• And: Fix with boolean, never, any b38ac60
• IsStringLiteral: Fix uncollapsed unions, and tagged types eb37799 / d1b35c7
• Paths: Fix behavior with index signatures 9926e5d
• ConditionalKeys: Fix behavior with arrays and unions 4d7cc50
• RequiredDeep: Fix with undefined bfcdbc4
• Split: Fix template strings ending with interpolation 853b881
• ArrayTail: Fix fix non-tuple arrays f3aabd8
• Fix UnionMin and UnionMax d52d5e7

Meta

Huge thanks to all the contributors to this release, especially @som-sm 🙌

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v4.41.0...v5.0.0

v4.41.0

• Add SetNonNullableDeep type (#1117) b9606e7
• LessThan / GreaterThan / GreaterThanOrEqual: Fix behaviour with unions (#1116) afd809a
• RequireAllOrNone / RequireAtLeastOne / RequireExactlyOne / RequireOneOrNone: Fix behaviour with any and never (#1113) 8c154e9

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v4.40.1...v4.41.0

v4.40.1

• PartialDeep: Fix behaviour with functions containing properties (#1108) 86a3a69
• CamelCasedPropertiesDeep / DelimiterCasedPropertiesDeep / KebabCasedPropertiesDeep / PascalCasedPropertiesDeep / SnakeCasedPropertiesDeep: Fix behaviour when property value is unknown (#1112) cfcf9ec

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v4.40.0...v4.40.1

v4.40.0

• Add NonEmptyString type (#1103) 19a9c37
• Add UnknownMap type (#1106) b4ace2d
• Add UnknownSet type (#1106) b4ace2d
• IsFloat / IsInteger: Fix instantiations with numbers represented using exponential notation (#1101) 21a92f6

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v4.39.1...v4.40.0

v4.39.1

• OptionalKeysOf / WritableKeysOf: Fix generic assignability with keyof T (#1098) 1b41ed3

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v4.39.0...v4.39.1

v4.39.0

• ArrayTail: Add preserveReadonly option (#1091) 544271e
• PartialDeep : Fix behaviour when strictNullChecks is disabled (#1096) 7536bae
• OptionalKeysOf / RequiredKeysOf: Fix instantiations with unions and arrays (#1089) e1ac7b2
• WritableKeysOf / ReadonlyKeysOf: Fix behavior with unions and optional properties (#1088) bbf9137

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v4.38.0...v4.39.0

v4.38.0

• AsyncReturnType: Add support for PromiseLike (#1082) 72ccde9
• DelimiterCase / SnakeCase / ScreamingSnakeCase / KebabCase: Fix instantiations containing punctuations (#1080) 063e28d
• DelimiterCase: Pass Options generic to all related types (#1078) 1974944
• CamelCasedPropertiesDeep: Make nested array objects respect the options (#1077) c11c9ca

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v4.37.0...v4.38.0

v4.37.0

• Sum: Add negative return value support (#1068) af5bfb7
• Subtract: Add negative return value support (#1061) 2b85ae2
• Split: Add strictLiteralChecks option (#1067) cc93f85
• Split: Fix instantiations with unions (#1067) cc93f85
• Replace: Fix instantiations with unions (#1065) a733698
• DelimiterCase / SnakeCase / ScreamingSnakeCase / KebabCase: Fix default value for splitOnNumbers option (#1073) e462e72

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v4.36.0...v4.37.0