feat: unify casing libraries — komoji as origin of truth

packages/inflekt/package.json

@@ -41,6 +41,7 @@
     "makage": "0.1.10"
   },
   "dependencies": {
-    "inflection": "^3.0.0"
+    "inflection": "^3.0.0",
+    "komoji": "workspace:*"
   }
 }

packages/inflekt/src/case.ts

@@ -1,21 +1,27 @@
 /**
  * Case transformation utilities
+ *
+ * Pure case transforms are delegated to komoji (the origin of truth).
+ * This module re-exports them for backward compatibility and adds
+ * inflekt-specific helpers (fixCapitalisedPlural, underscore, toScreamingSnake).
  */
 
-/**
- * Convert PascalCase to camelCase (lowercase first character)
- * @example "UserProfile" -> "userProfile"
- */
-export function lcFirst(str: string): string {
-  return str.charAt(0).toLowerCase() + str.slice(1);
-}
+import {
+  lcFirst,
+  ucFirst,
+  toCamelCase as _toCamelCase,
+  toPascalCase,
+  toSnakeCase,
+  toConstantCase,
+} from 'komoji';
 
-/**
- * Convert camelCase to PascalCase (uppercase first character)
- * @example "userProfile" -> "UserProfile"
- */
-export function ucFirst(str: string): string {
-  return str.charAt(0).toUpperCase() + str.slice(1);
+// Re-export komoji functions directly
+export { lcFirst, ucFirst, toPascalCase, toSnakeCase, toConstantCase };
+
+// Re-export toCamelCase — komoji's version accepts a second parameter
+// (stripLeadingNonAlphabetChars) so we wrap to keep the simpler inflekt signature
+export function toCamelCase(str: string): string {
+  return _toCamelCase(str);
 }
 
 /**
@@ -29,51 +35,20 @@ export function fixCapitalisedPlural(str: string): string {
 
 /**
  * Convert PascalCase or camelCase to snake_case
+ * @deprecated Use toSnakeCase from komoji instead
  * @example underscore('UserProfile') -> 'user_profile'
  * @example underscore('userProfile') -> 'user_profile'
  */
 export function underscore(str: string): string {
-  return str
-    .replace(/([A-Z])/g, '_$1')
-    .replace(/^_/, '')
-    .toLowerCase();
-}
-
-/**
- * Convert a hyphenated, underscored, or already-camelCased string to camelCase.
- * Handles both `-` and `_` delimiters.
- * @example toCamelCase('user-profile') -> 'userProfile'
- * @example toCamelCase('user_profile') -> 'userProfile'
- * @example toCamelCase('UserProfile') -> 'userProfile'
- */
-export function toCamelCase(str: string): string {
-  return str
-    .replace(/[-_](.)/g, (_, char) => char.toUpperCase())
-    .replace(/^(.)/, (_, char) => char.toLowerCase());
-}
-
-/**
- * Convert a hyphenated, underscored, or already-camelCased string to PascalCase.
- * Handles both `-` and `_` delimiters.
- * @example toPascalCase('user-profile') -> 'UserProfile'
- * @example toPascalCase('user_profile') -> 'UserProfile'
- * @example toPascalCase('userProfile') -> 'UserProfile'
- */
-export function toPascalCase(str: string): string {
-  return str
-    .replace(/[-_](.)/g, (_, char) => char.toUpperCase())
-    .replace(/^(.)/, (_, char) => char.toUpperCase());
+  return toSnakeCase(str);
 }
 
 /**
  * Convert a camelCase or PascalCase string to SCREAMING_SNAKE_CASE.
+ * @deprecated Use toConstantCase from komoji instead
  * @example toScreamingSnake('userProfile') -> 'USER_PROFILE'
  * @example toScreamingSnake('UserProfile') -> 'USER_PROFILE'
  */
 export function toScreamingSnake(str: string): string {
-  return str
-    .replace(/([A-Z])/g, '_$1')
-    .replace(/[-\s]/g, '_')
-    .toUpperCase()
-    .replace(/^_/, '');
+  return toConstantCase(str);
 }

packages/komoji/__tests__/casing.test.ts

@@ -1,4 +1,6 @@
 import {
+  lcFirst,
+  ucFirst,
   isValidIdentifier,
   isValidIdentifierCamelized,
   toCamelCase,
@@ -41,6 +43,40 @@ it('should validate valid JavaScript-like identifiers allowing internal hyphens'
   expect(isValidIdentifierCamelized('invalid-identifier-')).toBe(true);
 });
 
+describe('lcFirst', () => {
+  test('lowercases the first character', () => {
+    expect(lcFirst('UserProfile')).toBe('userProfile');
+    expect(lcFirst('User')).toBe('user');
+    expect(lcFirst('ABC')).toBe('aBC');
+  });
+
+  test('handles already lowercase strings', () => {
+    expect(lcFirst('user')).toBe('user');
+  });
+
+  test('handles single character', () => {
+    expect(lcFirst('A')).toBe('a');
+    expect(lcFirst('a')).toBe('a');
+  });
+});
+
+describe('ucFirst', () => {
+  test('uppercases the first character', () => {
+    expect(ucFirst('userProfile')).toBe('UserProfile');
+    expect(ucFirst('user')).toBe('User');
+    expect(ucFirst('abc')).toBe('Abc');
+  });
+
+  test('handles already uppercase strings', () => {
+    expect(ucFirst('User')).toBe('User');
+  });
+
+  test('handles single character', () => {
+    expect(ucFirst('a')).toBe('A');
+    expect(ucFirst('A')).toBe('A');
+  });
+});
+
 describe('toPascalCase', () => {
   test('converts normal string', () => {
     expect(toPascalCase('hello_world')).toBe('HelloWorld');
@@ -56,6 +92,18 @@ describe('toPascalCase', () => {
     expect(toPascalCase('hello___world--great')).toBe('HelloWorldGreat');
   });
 
+  test('handles consecutive mixed separators', () => {
+    expect(toPascalCase('my__double_under')).toBe('MyDoubleUnder');
+    expect(toPascalCase('my-_mixed-_sep')).toBe('MyMixedSep');
+    expect(toPascalCase('my--double-dash')).toBe('MyDoubleDash');
+  });
+
+  test('handles leading separators', () => {
+    expect(toPascalCase('_private')).toBe('Private');
+    expect(toPascalCase('__double')).toBe('Double');
+    expect(toPascalCase('-leading')).toBe('Leading');
+  });
+
   test('handles single word', () => {
     expect(toPascalCase('word')).toBe('Word');
   });
@@ -67,6 +115,11 @@ describe('toPascalCase', () => {
   test('handles string with numbers', () => {
     expect(toPascalCase('version1_2_3')).toBe('Version123');
   });
+
+  test('handles spaces', () => {
+    expect(toPascalCase('my table name')).toBe('MyTableName');
+    expect(toPascalCase('My Table Name')).toBe('MyTableName');
+  });
 });
 
 describe('toCamelCase', () => {

packages/komoji/src/index.ts

@@ -1,9 +1,25 @@
+/**
+ * Lowercase the first character of a string
+ * @example "UserProfile" -> "userProfile"
+ */
+export function lcFirst(str: string): string {
+  return str.charAt(0).toLowerCase() + str.slice(1);
+}
+
+/**
+ * Uppercase the first character of a string
+ * @example "userProfile" -> "UserProfile"
+ */
+export function ucFirst(str: string): string {
+  return str.charAt(0).toUpperCase() + str.slice(1);
+}
+
 export function toPascalCase(str: string) {
   return str
-    .replace(/(^|_|\s|-)(\w)/g, (_: any, __: any, letter: string) =>
-      letter.toUpperCase()
-    )
-    .replace(/[_\s-]/g, '');
+    // Convert what follows one-or-more separators into upper case (handles consecutive separators)
+    .replace(/[-_\s]+(.)?/g, (_, c) => (c ? c.toUpperCase() : ''))
+    // Ensure the first character is always uppercase
+    .replace(/^./, (c) => c.toUpperCase());
 }
 
 export function toCamelCase(