pluralize: avoid double pluralization

Author: tippenein

Text/Countable.hs

@@ -49,7 +49,7 @@ data Inflection
 pluralize :: Text -> Text
 pluralize = pluralizeWith mapping
   where
-    mapping = defaultIrregulars ++ defaultUncountables ++ defaultPlurals
+    mapping = defaultUncountables ++ defaultPlurals ++ irregularPluralsAsUncountables ++ defaultIrregulars
 
 -- | singularize a word given a default mapping
 singularize :: Text -> Text
@@ -149,3 +149,8 @@ regexPattern pat = toMaybe reg
 headMaybe :: [a] -> Maybe a
 headMaybe [] = Nothing
 headMaybe (x:_) = Just x
+
+-- Treat irregular plurals as uncountables to avoid double pluralization
+irregularPluralsAsUncountables :: [Inflection]
+irregularPluralsAsUncountables =
+  makeUncountableMapping (map snd defaultIrregulars')

test/Text/CountableSpec.hs

@@ -46,6 +46,9 @@ matchingCases = do
       pluralize "ox" `shouldBe` "oxen"
       pluralize "vertex" `shouldBe` "vertices"
 
+    it "can doesn't pluralize plurals a second time" $
+      pluralize "people" `shouldBe` "people"
+
   describe "singularize" $ do
     it "singularizes regex cases" $ do
       singularize "mice" `shouldBe` "mouse"
@@ -59,4 +62,4 @@ matchingCases = do
 irregularCases :: Spec
 irregularCases =
   it "can singularize irregulars" $
-    singularize "people" `shouldBe` "person"
+    singularize "people" `shouldBe` "person"