fix: singularizing and pluralizing focus

fixes #61

Author: p-kuen

src/inflection.ts

@@ -391,6 +391,7 @@ const regex = {
     tium: new RegExp('([ti])um$', 'gi'),
     sis: new RegExp('sis$', 'gi'),
     ffe: new RegExp('(?:([^f])fe|([lr])f)$', 'gi'),
+    focus: new RegExp('^(focus)$', 'gi'),
     hive: new RegExp('(hi|ti)ve$', 'gi'),
     aeiouyy: new RegExp('([^aeiouy]|qu)y$', 'gi'),
     x: new RegExp('(x|ch|ss|sh)$', 'gi'),
@@ -459,6 +460,7 @@ const pluralRules: [RegExp, string?][] = [
   [regex.singular.tium, '$1a'],
   [regex.singular.sis, 'ses'],
   [regex.singular.ffe, '$1$2ves'],
+  [regex.singular.focus, '$1es'],
   [regex.singular.hive, '$1ves'],
   [regex.singular.aeiouyy, '$1ies'],
   [regex.singular.matrix, '$1ices'],
@@ -496,6 +498,7 @@ const singularRules: [RegExp, string?][] = [
   [regex.singular.tium],
   [regex.singular.sis],
   [regex.singular.ffe],
+  [regex.singular.focus],
   [regex.singular.hive],
   [regex.singular.aeiouyy],
   [regex.singular.x],

test/inflection.test.ts

@@ -3,6 +3,7 @@ import { describe, it, expect } from 'vitest';
 
 describe('test .pluralize', function () {
   it('should pluralize the given word', function () {
+    expect(inflection.pluralize('accommodation')).toEqual('accommodation');
     expect(inflection.pluralize('people')).toEqual('people');
     expect(inflection.pluralize('men')).toEqual('men');
     expect(inflection.pluralize('women')).toEqual('women');
@@ -16,6 +17,7 @@ describe('test .pluralize', function () {
     expect(inflection.pluralize('life')).toEqual('lives');
     expect(inflection.pluralize('bath')).toEqual('baths');
     expect(inflection.pluralize('calf')).toEqual('calves');
+    expect(inflection.pluralize('focus')).toEqual('focuses');
     expect(inflection.pluralize('foot')).toEqual('feet');
     expect(inflection.pluralize('book')).toEqual('books');
     expect(inflection.pluralize('goose')).toEqual('geese');
@@ -67,6 +69,7 @@ describe('test .singularize', function () {
     expect(inflection.singularize('baths')).toEqual('bath');
     expect(inflection.singularize('calves')).toEqual('calf');
     expect(inflection.singularize('feet')).toEqual('foot');
+    expect(inflection.singularize('focus')).toEqual('focus');
     expect(inflection.singularize('books')).toEqual('book');
     expect(inflection.singularize('geese')).toEqual('goose');
     expect(inflection.singularize('teeth')).toEqual('tooth');