feat: export type helpers (#58)

unjs · Nov 15, 2023 · a83e505 · a83e505
1 parent ba39ce6
commit a83e505
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Showing 2 changed files with 35 additions and 17 deletions.
diff --git a/src/index.ts b/src/index.ts
@@ -1,4 +1,10 @@
-import { CamelCase, JoinByCase, PascalCase, SplitByCase } from "./types";
+import type {
+  CamelCase,
+  KebabCase,
+  PascalCase,
+  SnakeCase,
+  SplitByCase,
+} from "./types";
 
 const NUMBER_CHAR_RE = /\d/;
 const STR_SPLITTERS = ["-", "_", "/", "."] as const;
@@ -106,26 +112,28 @@ export function camelCase<T extends string | readonly string[]>(string_?: T) {
 export function kebabCase(): "";
 export function kebabCase<T extends string | readonly string[]>(
   string_: T,
-): JoinByCase<T, "-">;
+): KebabCase<T>;
 export function kebabCase<
   T extends string | readonly string[],
   Joiner extends string,
->(string_: T, joiner: Joiner): JoinByCase<T, Joiner>;
+>(string_: T, joiner: Joiner): KebabCase<T, Joiner>;
 export function kebabCase<
   T extends string | readonly string[],
   Joiner extends string,
 >(string_?: T, joiner?: Joiner) {
   return string_
     ? ((Array.isArray(string_) ? string_ : splitByCase(string_ as string))
         .map((p) => p.toLowerCase())
-        .join(joiner ?? "-") as JoinByCase<T, Joiner>)
+        .join(joiner ?? "-") as KebabCase<T, Joiner>)
     : "";
 }
 
 export function snakeCase(): "";
 export function snakeCase<T extends string | readonly string[]>(
   string_: T,
-): JoinByCase<T, "_">;
+): SnakeCase<T>;
 export function snakeCase<T extends string | readonly string[]>(string_?: T) {
-  return kebabCase(string_ || "", "_") as JoinByCase<T, "_">;
+  return kebabCase(string_ || "", "_") as SnakeCase<T>;
 }
+
+export * from "./types";
diff --git a/src/types.ts b/src/types.ts
@@ -99,6 +99,18 @@ export type SplitByCase<
         : string[]
       : Accumulator;
 
+type JoinByCase<T, Joiner extends string> = string extends T
+  ? string
+  : string[] extends T
+    ? string
+    : T extends string
+      ? SplitByCase<T> extends readonly string[]
+        ? JoinLowercaseWords<SplitByCase<T>, Joiner>
+        : never
+      : T extends readonly string[]
+        ? JoinLowercaseWords<T, Joiner>
+        : never;
+
 export type PascalCase<T> = string extends T
   ? string
   : string[] extends T
@@ -117,17 +129,15 @@ export type CamelCase<T> = string extends T
     ? string
     : Uncapitalize<PascalCase<T>>;
 
-export type JoinByCase<T, Joiner extends string> = string extends T
-  ? string
-  : string[] extends T
-    ? string
-    : T extends string
-      ? SplitByCase<T> extends readonly string[]
-        ? JoinLowercaseWords<SplitByCase<T>, Joiner>
-        : never
-      : T extends readonly string[]
-        ? JoinLowercaseWords<T, Joiner>
-        : never;
+export type KebabCase<
+  T extends string | readonly string[],
+  Joiner extends string = "-",
+> = JoinByCase<T, Joiner>;
+
+export type SnakeCase<T extends string | readonly string[]> = JoinByCase<
+  T,
+  "_"
+>;
 
 // eslint-disable-next-line @typescript-eslint/no-unused-vars
 type __tests = [