add default-value via init-storage

crates/gpui_elements/src/editable_text.rs

@@ -16,7 +16,7 @@ pub use text_area_element::*;
 pub use text_area_state::*;
 
 /* TODO list
-- default-value
+- disabled input/area
 - remove gpuikit based input
 - cursor blinking
 - color styling configs
@@ -24,5 +24,9 @@ pub use text_area_state::*;
 - text sanitation
 - test IME (char palette only available on macos)
 - unit tests
-- disabled input/area
+*/
+
+/* Open questions:
+Is is practical and worthwhile to have separate element and state implementations?
+The only real difference is how some input-action handler functions are processed.
 */

crates/gpui_elements/src/editable_text/input_element.rs

@@ -42,10 +42,21 @@ impl TextInputElement {
         self
     }
 
+    /// Swaps the default storage container (standard String) with a custom initializer of [`UnicodeTextStorage`].
     pub fn with_storage(mut self, fn_init: impl Into<InitStorage>) -> Self {
         self.init_storage = fn_init.into();
         self
     }
+
+    /// Swaps the default storage container. The new initializer is a standard String using the provided value.
+    ///
+    /// Incompatible with [`with_storage`] (they establish the same internal value).
+    /// If you initialize custom storage, you should be able to initialize its default value.
+    pub fn default_value(mut self, value: impl Into<String>) -> Self {
+        let storage = super::StringStorage::from(value.into());
+        self.init_storage = InitStorage::new_typed(move |_cx| storage.clone());
+        self
+    }
 }
 
 impl InteractiveElement for TextInputElement {

crates/gpui_elements/src/editable_text/storage.rs

@@ -16,18 +16,24 @@ pub enum TextBoundary {
 #[derive(Clone, Default)]
 pub struct InitStorage(Option<Rc<dyn Fn(&mut App) -> Box<dyn UnicodeTextStorage>>>);
 
-// TODO: Doesnt yet compile in practice "implementation of Fn is not general enough"
-// InitStorage::from(|_cx| Box::new(StringStorage::default()) as Box<dyn UnicodeTextStorage>);
-impl<F> From<F> for InitStorage
-where
-    F: 'static + for<'app> Fn(&'app mut App) -> Box<dyn UnicodeTextStorage>,
-{
-    fn from(value: F) -> Self {
-        Self(Some(Rc::new(value)))
-    }
-}
-
 impl InitStorage {
+    pub fn new_generic<F>(f: F) -> Self
+    where
+        F: 'static + Fn(&mut App) -> Box<dyn UnicodeTextStorage>,
+    {
+        Self(Some(Rc::new(f)))
+    }
+
+    pub fn new_typed<F, R>(f: F) -> Self
+    where
+        F: 'static + Fn(&mut App) -> R,
+        R: 'static + UnicodeTextStorage,
+    {
+        Self(Some(Rc::new(move |cx| {
+            Box::new(f(cx)) as Box<dyn UnicodeTextStorage>
+        })))
+    }
+
     pub(super) fn exec(&self, cx: &mut App) -> Box<dyn UnicodeTextStorage> {
         match &self.0 {
             None => Box::new(StringStorage::default()),
@@ -229,7 +235,7 @@ pub trait UnicodeTextStorage {
     }
 }
 
-#[derive(Default)]
+#[derive(Clone, Default)]
 pub struct StringStorage {
     value: String,
     version: u16,

crates/gpui_elements/src/editable_text/text_area_element.rs

@@ -41,10 +41,21 @@ impl EditableTextAreaElement {
         self
     }
 
+    /// Swaps the default storage container (standard String) with a custom initializer of [`UnicodeTextStorage`].
     pub fn with_storage(mut self, fn_init: impl Into<InitStorage>) -> Self {
         self.init_storage = fn_init.into();
         self
     }
+
+    /// Swaps the default storage container. The new initializer is a standard String using the provided value.
+    ///
+    /// Incompatible with [`with_storage`] (they establish the same internal value).
+    /// If you initialize custom storage, you should be able to initialize its default value.
+    pub fn default_value(mut self, value: impl Into<String>) -> Self {
+        let storage = super::StringStorage::from(value.into());
+        self.init_storage = InitStorage::new_typed(move |_cx| storage.clone());
+        self
+    }
 }
 
 impl InteractiveElement for EditableTextAreaElement {