fix: pluralization of words ending in y, where y follows a vowel (#10697)

Fixes: FRMW-2851

.changeset/unlucky-carpets-remain.md

@@ -0,0 +1,5 @@
+---
+"@medusajs/types": patch
+---
+
+fix: pluralization of words ending in y, where y follows a vowel

packages/core/types/src/common/__tests__/pluralize.spec.ts

@@ -18,6 +18,11 @@ describe("Pluralize", () => {
     expectTypeOf<Pluralize<"knife">>().toEqualTypeOf<"knives">()
   })
 
+  test("pluralize words ending with ch", () => {
+    expectTypeOf<Pluralize<"church">>().toEqualTypeOf<"churches">()
+    expectTypeOf<Pluralize<"arch">>().toEqualTypeOf<"arches">()
+  })
+
   test("pluralize words ending with o", () => {
     expectTypeOf<Pluralize<"hero">>().toEqualTypeOf<"heroes">()
   })
@@ -30,8 +35,20 @@ describe("Pluralize", () => {
     expectTypeOf<Pluralize<"fiz">>().toEqualTypeOf<"fizes">()
   })
 
-  test("pluralize words ending with y", () => {
+  test("pluralize words ending with y, in which y follows a constant", () => {
     expectTypeOf<Pluralize<"puppy">>().toEqualTypeOf<"puppies">()
+    expectTypeOf<Pluralize<"twenty">>().toEqualTypeOf<"twenties">()
+    expectTypeOf<Pluralize<"copy">>().toEqualTypeOf<"copies">()
+  })
+
+  test("pluralize words ending with y, in which y follow a vowel", () => {
+    expectTypeOf<Pluralize<"play">>().toEqualTypeOf<"plays">()
+    expectTypeOf<Pluralize<"relay">>().toEqualTypeOf<"relays">()
+    expectTypeOf<Pluralize<"alley">>().toEqualTypeOf<"alleys">()
+    expectTypeOf<Pluralize<"alley">>().toEqualTypeOf<"alleys">()
+    expectTypeOf<Pluralize<"boy">>().toEqualTypeOf<"boys">()
+    expectTypeOf<Pluralize<"enjoy">>().toEqualTypeOf<"enjoys">()
+    expectTypeOf<Pluralize<"buy">>().toEqualTypeOf<"buys">()
   })
 
   test("pluralize words with special rules", () => {

packages/core/types/src/common/common.ts

@@ -365,26 +365,34 @@ export type Pluralize<Singular extends string> =
     ? PluralizationSpecialRules[Lowercase<Singular>]
     : Lowercase<Singular> extends UncountableRules
     ? Singular
-    : Singular extends `${infer R}ss`
+    : Singular extends `${string}ss`
     ? `${Singular}es`
     : Singular extends `${infer R}sis`
     ? `${R}ses`
     : Singular extends `${infer R}is`
     ? `${R}ises`
-    : Singular extends `${infer R}s`
+    : Singular extends `${string}s`
     ? `${Singular}`
+    : Singular extends `${infer R}ay`
+    ? `${R}ays`
     : Singular extends `${infer R}ey`
     ? `${R}eys`
+    : Singular extends `${infer R}iy`
+    ? `${R}iys`
+    : Singular extends `${infer R}oy`
+    ? `${R}oys`
+    : Singular extends `${infer R}uy`
+    ? `${R}uys`
     : Singular extends `${infer R}y`
     ? `${R}ies`
-    : Singular extends `${infer R}es`
+    : Singular extends `${string}es`
     ? `${Singular}`
     : Singular extends
-        | `${infer R}sh`
-        | `${infer R}ch`
-        | `${infer R}x`
-        | `${infer R}z`
-        | `${infer R}o`
+        | `${string}sh`
+        | `${string}ch`
+        | `${string}x`
+        | `${string}z`
+        | `${string}o`
     ? `${Singular}es`
     : Singular extends `${infer R}fe`
     ? `${R}ves`