feat: add parseISODuration for ISO 8601 duration parsing

test/Roux/SchemaOrgSpec.hs

@@ -1,6 +1,7 @@
 module Roux.SchemaOrgSpec (spec) where
 
 import qualified Data.Aeson as A
+import Data.CookLang (Duration (..))
 import Data.Maybe (fromJust, isJust)
 import Data.Text (Text)
 import qualified Data.Text as T
@@ -49,3 +50,16 @@ spec = describe "SchemaOrg" $ do
             case recipe of
                 Nothing -> expectationFailure "expected Just SchemaOrgRecipe, got Nothing"
                 Just r -> soName r `shouldBe` "Carrot Risotto With Chile Crisp"
+
+    describe "parseISODuration" $ do
+        let chk :: Text -> Maybe Duration -> IO ()
+            chk input expected = parseISODuration input `shouldBe` expected
+
+        it "PT20M -> 20 minutes" $ chk "PT20M" (Just (Duration 20 (Just "minutes")))
+        it "PT1H -> 60 minutes" $ chk "PT1H" (Just (Duration 60 (Just "minutes")))
+        it "PT1H30M -> 90 minutes" $ chk "PT1H30M" (Just (Duration 90 (Just "minutes")))
+        it "P1D -> 1440 minutes" $ chk "P1D" (Just (Duration 1440 (Just "minutes")))
+        it "P1DT2H -> 1560 minutes" $ chk "P1DT2H" (Just (Duration 1560 (Just "minutes")))
+        it "PT30M -> 30 minutes" $ chk "PT30M" (Just (Duration 30 (Just "minutes")))
+        it "empty string -> Nothing" $ chk "" Nothing
+        it "human-readable -> Nothing" $ chk "20 minutes" Nothing