Expose a bare minimum of HTML 5 Form validity

Users can set custom custom validity status. There are a number of
way/reason to get the validity info, and so nothing is exposed to get
it at this time.

reflex-dom-core/src/Reflex/Dom/Builder/Class.hs

@@ -249,13 +249,23 @@ data Element er d t
              , _element_raw :: RawElement d
              }
 
-data InputElementConfig er t s
-   = InputElementConfig { _inputElementConfig_initialValue :: Text
-                        , _inputElementConfig_setValue :: Maybe (Event t Text)
-                        , _inputElementConfig_initialChecked :: Bool
-                        , _inputElementConfig_setChecked :: Maybe (Event t Bool)
-                        , _inputElementConfig_elementConfig :: ElementConfig er t s
-                        }
+data InputElementConfig er t s = InputElementConfig
+  { _inputElementConfig_initialValue :: Text
+  , _inputElementConfig_setValue :: Maybe (Event t Text)
+  , _inputElementConfig_initialChecked :: Bool
+  , _inputElementConfig_setChecked :: Maybe (Event t Bool)
+  , _inputElementConfig_initialCustomValidity :: Text
+    -- ^ The initial custom validity status/message. An empty string indicates
+    -- valid, while a non-empty string indicates invalid. Custom validity is
+    -- just one endorser of validity; based on the type of the input various
+    -- other built-in checks may also deem the input invalid, and any one
+    -- invalid result makes the input invalid overall. '""' is thus the
+    -- identity.
+  , _inputElementConfig_setCustomValidity :: Maybe (Event t Text)
+    -- ^ An event that sets the custom validity. See the initial value
+    -- documentation for details.
+  , _inputElementConfig_elementConfig :: ElementConfig er t s
+  }
 
 #ifndef USE_TEMPLATE_HASKELL
 inputElementConfig_initialValue :: Lens' (InputElementConfig er t m) Text
@@ -280,6 +290,8 @@ instance (Reflex t, er ~ EventResult, DomSpace s) => Default (InputElementConfig
     , _inputElementConfig_setValue = Nothing
     , _inputElementConfig_initialChecked = False
     , _inputElementConfig_setChecked = Nothing
+    , _inputElementConfig_initialCustomValidity = ""
+    , _inputElementConfig_setCustomValidity = Nothing
     , _inputElementConfig_elementConfig = def
     }
 
@@ -294,11 +306,17 @@ data InputElement er d t
                   , _inputElement_files :: Dynamic t [RawFile d]
                   }
 
-data TextAreaElementConfig er t m
-   = TextAreaElementConfig { _textAreaElementConfig_initialValue :: Text
-                           , _textAreaElementConfig_setValue :: Maybe (Event t Text)
-                           , _textAreaElementConfig_elementConfig :: ElementConfig er t m
-                           }
+data TextAreaElementConfig er t m = TextAreaElementConfig
+  { _textAreaElementConfig_initialValue :: Text
+  , _textAreaElementConfig_setValue :: Maybe (Event t Text)
+  , _textAreaElementConfig_initialCustomValidity :: Text
+    -- ^ The initial custom validity status/message. See same field on 'InputElementConfig' for details.
+  , _textAreaElementConfig_setCustomValidity :: Maybe (Event t Text)
+    -- ^ An event that sets the custom validity. See the 'initialCustomValidity'
+    -- and 'setCustomValidity' fields on 'InputElementConfig' for details.
+    -- documentation for details.
+  , _textAreaElementConfig_elementConfig :: ElementConfig er t m
+  }
 
 #ifndef USE_TEMPLATE_HASKELL
 textAreaElementConfig_initialValue :: Lens' (TextAreaElementConfig er t m) Text
@@ -318,6 +336,7 @@ instance (Reflex t, er ~ EventResult, DomSpace s) => Default (TextAreaElementCon
   def = TextAreaElementConfig
     { _textAreaElementConfig_initialValue = ""
     , _textAreaElementConfig_setValue = Nothing
+    , _textAreaElementConfig_setCustomValidity = Nothing
     , _textAreaElementConfig_elementConfig = def
     }
 
@@ -394,10 +413,12 @@ data SelectElement er d t = SelectElement
 concat <$> mapM (uncurry makeLensesWithoutField)
   [ (["_textNodeConfig_setContents"], ''TextNodeConfig)
   , ([ "_inputElementConfig_setValue"
-     , "_inputElementConfig_setChecked" ], ''InputElementConfig)
+     , "_inputElementConfig_setChecked"
+     , "_inputElementConfig_setCustomValidity" ], ''InputElementConfig)
   , (["_rawElementConfig_modifyAttributes"], ''RawElementConfig)
   , (["_elementConfig_modifyAttributes"], ''ElementConfig)
-  , (["_textAreaElementConfig_setValue"], ''TextAreaElementConfig)
+  , ([ "_textAreaElementConfig_setValue"
+     , "_textAreaElementConfig_setCustomValidity" ], ''TextAreaElementConfig)
   , (["_selectElementConfig_setValue"], ''SelectElementConfig)
   ]
 #endif
@@ -423,6 +444,13 @@ inputElementConfig_setChecked =
       setter t e = t { _inputElementConfig_setChecked = Just e }
   in lens getter setter
 
+-- | This lens is technically illegal. The implementation of 'InputElementConfig' uses a 'Maybe' under the hood for efficiency reasons. However, always interacting with 'InputElementConfig' via lenses will always behave correctly, and if you pattern match on it, you should always treat 'Nothing' as 'never'.
+inputElementConfig_setCustomValidity :: Reflex t => Lens' (InputElementConfig er t m) (Event t Text)
+inputElementConfig_setCustomValidity =
+  let getter = fromMaybe never . _inputElementConfig_setCustomValidity
+      setter t e = t { _inputElementConfig_setCustomValidity = Just e }
+  in lens getter setter
+
 -- | This lens is technically illegal. The implementation of 'RawElementConfig' uses a 'Maybe' under the hood for efficiency reasons. However, always interacting with 'RawElementConfig' via lenses will always behave correctly, and if you pattern match on it, you should always treat 'Nothing' as 'never'.
 rawElementConfig_modifyAttributes :: Reflex t => Lens' (RawElementConfig er t m) (Event t (Map AttributeName (Maybe Text)))
 rawElementConfig_modifyAttributes =
@@ -444,6 +472,13 @@ textAreaElementConfig_setValue =
       setter t e = t { _textAreaElementConfig_setValue = Just e }
   in lens getter setter
 
+-- | This lens is technically illegal. The implementation of 'TextAreaElementConfig' uses a 'Maybe' under the hood for efficiency reasons. However, always interacting with 'TextAreaElementConfig' via lenses will always behave correctly, and if you pattern match on it, you should always treat 'Nothing' as 'never'.
+textAreaElementConfig_setCustomValidity :: Reflex t => Lens' (TextAreaElementConfig er t m) (Event t Text)
+textAreaElementConfig_setCustomValidity =
+  let getter = fromMaybe never . _textAreaElementConfig_setCustomValidity
+      setter t e = t { _textAreaElementConfig_setCustomValidity = Just e }
+  in lens getter setter
+
 -- | This lens is technically illegal. The implementation of 'SelectElementConfig' uses a 'Maybe' under the hood for efficiency reasons. However, always interacting with 'SelectElementConfig' via lenses will always behave correctly, and if you pattern match on it, you should always treat 'Nothing' as 'never'.
 selectElementConfig_setValue :: Reflex t => Lens' (SelectElementConfig er t m) (Event t Text)
 selectElementConfig_setValue =

reflex-dom-core/src/Reflex/Dom/Builder/Immediate.hs

@@ -469,6 +469,7 @@ instance SupportsImmediateDomBuilder t m => DomBuilder t (ImmediateDomBuilderT t
     ((e, _), domElement) <- makeElement "input" (cfg ^. inputElementConfig_elementConfig) $ return ()
     let domInputElement = uncheckedCastTo DOM.HTMLInputElement domElement
     Input.setValue domInputElement $ cfg ^. inputElementConfig_initialValue
+    Input.setCustomValidity domInputElement $ cfg ^. inputElementConfig_initialCustomValidity
     v0 <- Input.getValue domInputElement
     let getMyValue = Input.getValue domInputElement
     valueChangedByUI <- requestDomAction $ liftJSM getMyValue <$ Reflex.select (_element_events e) (WrapArg Input)
@@ -496,6 +497,10 @@ instance SupportsImmediateDomBuilder t m => DomBuilder t (ImmediateDomBuilderT t
       [ fmapMaybe id checkedChangedBySetChecked
       , checkedChangedByUI
       ]
+    case _inputElementConfig_setCustomValidity cfg of
+      Nothing -> pure ()
+      Just eSetInvalid -> void $ requestDomAction $ ffor eSetInvalid $ \v' -> do
+        Input.setCustomValidity domInputElement v'
     let initialFocus = False --TODO: Is this correct?
     hasFocus <- holdDyn initialFocus $ leftmost
       [ False <$ Reflex.select (_element_events e) (WrapArg Blur)
@@ -521,6 +526,7 @@ instance SupportsImmediateDomBuilder t m => DomBuilder t (ImmediateDomBuilderT t
     ((e, _), domElement) <- makeElement "textarea" (cfg ^. textAreaElementConfig_elementConfig) $ return ()
     let domTextAreaElement = uncheckedCastTo DOM.HTMLTextAreaElement domElement
     TextArea.setValue domTextAreaElement $ cfg ^. textAreaElementConfig_initialValue
+    TextArea.setCustomValidity domTextAreaElement $ cfg ^. textAreaElementConfig_initialCustomValidity
     v0 <- TextArea.getValue domTextAreaElement
     let getMyValue = TextArea.getValue domTextAreaElement
     valueChangedByUI <- requestDomAction $ liftJSM getMyValue <$ Reflex.select (_element_events e) (WrapArg Input)
@@ -533,6 +539,10 @@ instance SupportsImmediateDomBuilder t m => DomBuilder t (ImmediateDomBuilderT t
       [ valueChangedBySetValue
       , valueChangedByUI
       ]
+    case _textAreaElementConfig_setCustomValidity cfg of
+      Nothing -> pure ()
+      Just eSetInvalid -> void $ requestDomAction $ ffor eSetInvalid $ \v' -> do
+        void $ TextArea.setCustomValidity domTextAreaElement v'
     hasFocus <- mkHasFocus e
     return $ TextAreaElement
       { _textAreaElement_value = v