Add delimiter option to change-case

Author: blakeembrey

packages/change-case/README.md

@@ -35,6 +35,7 @@ Included case functions:
 
 All methods accept an `options` object as the second argument:
 
+- `delimiter?: string` The character to use between words. Default depends on method, e.g. `_` in snake case.
 - `locale?: string[] | string | false` Lower/upper according to specified locale, defaults to host environment. Set to `false` to disable.
 - `separateNumbers?: boolean` Splits `foo123` into `foo 123` instead of keeping them together. Defaults to `true`.
 - `prefixCharacters?: string` Retain at the beginning of the string. Defaults to `""`. Example: use `"_"` to keep the underscores in `__typename`.

packages/change-case/src/index.spec.ts

@@ -104,6 +104,27 @@ const tests: [string, Result, Options?][] = [
       trainCase: "Test-String",
     },
   ],
+  [
+    "Test String",
+    {
+      split: ["Test", "String"],
+      camelCase: "test$String",
+      capitalCase: "Test$String",
+      constantCase: "TEST$STRING",
+      dotCase: "test$string",
+      kebabCase: "test$string",
+      noCase: "test$string",
+      pascalCase: "Test$String",
+      pascalSnakeCase: "Test$String",
+      pathCase: "test$string",
+      sentenceCase: "Test$string",
+      snakeCase: "test$string",
+      trainCase: "Test$String",
+    },
+    {
+      delimiter: "$",
+    },
+  ],
   [
     "TestV2",
     {

packages/change-case/src/index.ts

@@ -21,6 +21,7 @@ export type Locale = string[] | string | false | undefined;
 
 export interface Options extends SplitOptions {
   locale?: Locale;
+  delimiter?: string;
   prefixCharacters?: string;
 }
 
@@ -67,7 +68,7 @@ export function noCase(input: string, options?: Options) {
     prefix +
     split(input, options)
       .map(lowerFactory(options?.locale))
-      .join(" ")
+      .join(options?.delimiter ?? " ")
   );
 }
 
@@ -86,7 +87,7 @@ export function camelCase(input: string, options?: Options) {
         if (index === 0) return lower(word);
         return transform(word, index);
       })
-      .join("")
+      .join(options?.delimiter ?? "")
   );
 }
 
@@ -99,23 +100,17 @@ export function pascalCase(input: string, options?: Options) {
   const upper = upperFactory(options?.locale);
   return (
     prefix +
-    split(input, options).map(pascalCaseTransformFactory(lower, upper)).join("")
+    split(input, options)
+      .map(pascalCaseTransformFactory(lower, upper))
+      .join(options?.delimiter ?? "")
   );
 }
 
 /**
  * Convert a string to pascal snake case (`Foo_Bar`).
  */
 export function pascalSnakeCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  const upper = upperFactory(options?.locale);
-  return (
-    prefix +
-    split(input, options)
-      .map(capitalCaseTransformFactory(lower, upper))
-      .join("_")
-  );
+  return capitalCase(input, { delimiter: "_", ...options });
 }
 
 /**
@@ -129,7 +124,7 @@ export function capitalCase(input: string, options?: Options) {
     prefix +
     split(input, options)
       .map(capitalCaseTransformFactory(lower, upper))
-      .join(" ")
+      .join(options?.delimiter ?? " ")
   );
 }
 
@@ -138,35 +133,33 @@ export function capitalCase(input: string, options?: Options) {
  */
 export function constantCase(input: string, options?: Options) {
   const prefix = getPrefix(input, options?.prefixCharacters);
-  const upper = upperFactory(options?.locale);
-  return prefix + split(input, options).map(upper).join("_");
+  return (
+    prefix +
+    split(input, options)
+      .map(upperFactory(options?.locale))
+      .join(options?.delimiter ?? "_")
+  );
 }
 
 /**
  * Convert a string to dot case (`foo.bar`).
  */
 export function dotCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  return prefix + split(input, options).map(lower).join(".");
+  return noCase(input, { delimiter: ".", ...options });
 }
 
 /**
  * Convert a string to kebab case (`foo-bar`).
  */
 export function kebabCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  return prefix + split(input, options).map(lower).join("-");
+  return noCase(input, { delimiter: "-", ...options });
 }
 
 /**
  * Convert a string to path case (`foo/bar`).
  */
 export function pathCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  return prefix + split(input, options).map(lower).join("/");
+  return noCase(input, { delimiter: "/", ...options });
 }
 
 /**
@@ -184,32 +177,22 @@ export function sentenceCase(input: string, options?: Options) {
         if (index === 0) return transform(word);
         return lower(word);
       })
-      .join(" ")
+      .join(options?.delimiter ?? " ")
   );
 }
 
 /**
  * Convert a string to snake case (`foo_bar`).
  */
 export function snakeCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  return prefix + split(input, options).map(lower).join("_");
+  return noCase(input, { delimiter: "_", ...options });
 }
 
 /**
  * Convert a string to header case (`Foo-Bar`).
  */
 export function trainCase(input: string, options?: Options) {
-  const prefix = getPrefix(input, options?.prefixCharacters);
-  const lower = lowerFactory(options?.locale);
-  const upper = upperFactory(options?.locale);
-  return (
-    prefix +
-    split(input, options)
-      .map(capitalCaseTransformFactory(lower, upper))
-      .join("-")
-  );
+  return capitalCase(input, { delimiter: "-", ...options });
 }
 
 function lowerFactory(locale: Locale): (input: string) => string {