Auto merge of #10612 - autrilla:textdir, r=emilio

Implement HTMLTextArea.setSelectionRange (continuation of #10007)

Tests on `tests/wpt/web-platform-tests/html/semantics/forms/textfieldselection/textfieldselection-setSelectionRange.html` all pass and the other tests don't panic due to double borrows anymore.

cc: @KiChjang

Fixes #9994.

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components/script/dom/htmlinputelement.rs

@@ -42,7 +42,7 @@ use string_cache::Atom;
 use style::element_state::*;
 use textinput::KeyReaction::{DispatchInput, Nothing, RedrawSelection, TriggerDefaultAction};
 use textinput::Lines::Single;
-use textinput::TextInput;
+use textinput::{TextInput, SelectionDirection};
 use util::str::{DOMString, search_index};
 
 const DEFAULT_SUBMIT_VALUE: &'static str = "Submit";
@@ -71,14 +71,6 @@ enum ValueMode {
     Filename,
 }
 
-#[derive(JSTraceable, PartialEq, Copy, Clone)]
-#[derive(HeapSizeOf)]
-enum SelectionDirection {
-    Forward,
-    Backward,
-    None
-}
-
 #[dom_struct]
 pub struct HTMLInputElement {
     htmlelement: HTMLElement,
@@ -94,8 +86,6 @@ pub struct HTMLInputElement {
     // https://html.spec.whatwg.org/multipage/#concept-input-value-dirty-flag
     value_dirty: Cell<bool>,
 
-    selection_direction: Cell<SelectionDirection>,
-
     // TODO: selected files for file input
 }
 
@@ -142,10 +132,9 @@ impl HTMLInputElement {
             value_changed: Cell::new(false),
             maxlength: Cell::new(DEFAULT_MAX_LENGTH),
             size: Cell::new(DEFAULT_INPUT_SIZE),
-            textinput: DOMRefCell::new(TextInput::new(Single, DOMString::new(), chan, None)),
+            textinput: DOMRefCell::new(TextInput::new(Single, DOMString::new(), chan, None, SelectionDirection::None)),
             activation_state: DOMRefCell::new(InputActivationState::new()),
             value_dirty: Cell::new(false),
-            selection_direction: Cell::new(SelectionDirection::None)
         }
     }
 
@@ -177,33 +166,6 @@ impl HTMLInputElement {
             InputType::InputFile => ValueMode::Filename,
         }
     }
-
-    // this method exists so that the functions SetSelectionStart() and SetSelectionEnd()
-    // don't needlessly allocate strings
-    fn set_selection_range(&self, start: u32, end: u32, direction: &SelectionDirection) {
-        let mut text_input = self.textinput.borrow_mut();
-
-        let mut start = start as usize;
-        let mut end = end as usize;
-
-        let text_end = text_input.get_content().len();
-        if start > text_end {
-            start = text_end;
-        }
-        if end > text_end {
-            end = text_end;
-        }
-
-        if start >= end {
-            start = end;
-        }
-
-        text_input.selection_begin = Some(text_input.get_text_point_for_absolute_point(start));
-        text_input.edit_point = text_input.get_text_point_for_absolute_point(end);
-        self.selection_direction.set(*direction);
-        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
-    }
-
 }
 
 pub trait LayoutHTMLInputElementHelpers {
@@ -547,60 +509,44 @@ impl HTMLInputElementMethods for HTMLInputElement {
 
     // https://html.spec.whatwg.org/multipage/#dom-input-selectionstart
     fn SelectionStart(&self) -> u32 {
-        let text_input = self.textinput.borrow();
-        let selection_start = match text_input.selection_begin {
-            Some(selection_begin_point) => {
-                text_input.get_absolute_point_for_text_point(&selection_begin_point)
-            },
-            None => text_input.get_absolute_insertion_point()
-        };
-
-        selection_start as u32
+        self.textinput.borrow().get_selection_start()
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
     fn SetSelectionStart(&self, start: u32) {
-        self.set_selection_range(start, self.SelectionEnd(), &self.selection_direction.get());
+        let selection_end = self.SelectionEnd();
+        self.textinput.borrow_mut().set_selection_range(start, selection_end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionend
     fn SelectionEnd(&self) -> u32 {
-        let text_input = self.textinput.borrow();
-        text_input.get_absolute_insertion_point() as u32
+        self.textinput.borrow().get_absolute_insertion_point() as u32
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionend
     fn SetSelectionEnd(&self, end: u32) {
-        self.set_selection_range(self.SelectionStart(), end, &self.selection_direction.get());
+        let selection_start = self.SelectionStart();
+        self.textinput.borrow_mut().set_selection_range(selection_start, end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectiondirection
     fn SelectionDirection(&self) -> DOMString {
-        match self.selection_direction.get() {
-            SelectionDirection::Forward => DOMString::from("forward"),
-            SelectionDirection::Backward => DOMString::from("backward"),
-            SelectionDirection::None => DOMString::from("none"),
-        }
+        DOMString::from(self.textinput.borrow().selection_direction)
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectiondirection
     fn SetSelectionDirection(&self, direction: DOMString) {
-        self.SetSelectionRange(self.SelectionStart(), self.SelectionEnd(), Some(direction));
+        self.textinput.borrow_mut().selection_direction = SelectionDirection::from(direction);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-setselectionrange
     fn SetSelectionRange(&self, start: u32, end: u32, direction: Option<DOMString>) {
-        let selection_direction = match direction {
-            Some(selection_direction) => {
-                match &*selection_direction {
-                    "forward" => SelectionDirection::Forward,
-                    "backward" => SelectionDirection::Backward,
-                    _ => SelectionDirection::None,
-                }
-            },
-            None => SelectionDirection::None,
-        };
-        self.set_selection_range(start, end, &selection_direction);
+        let direction = direction.map_or(SelectionDirection::None, |d| SelectionDirection::from(d));
+        self.textinput.borrow_mut().selection_direction = direction;
+        self.textinput.borrow_mut().set_selection_range(start, end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
     }
 }
 

components/script/dom/htmltextareaelement.rs

@@ -31,7 +31,7 @@ use script_traits::ScriptMsg as ConstellationMsg;
 use std::cell::Cell;
 use string_cache::Atom;
 use style::element_state::*;
-use textinput::{KeyReaction, Lines, TextInput};
+use textinput::{KeyReaction, Lines, TextInput, SelectionDirection};
 use util::str::DOMString;
 
 #[dom_struct]
@@ -106,7 +106,8 @@ impl HTMLTextAreaElement {
             htmlelement:
                 HTMLElement::new_inherited_with_state(IN_ENABLED_STATE,
                                                       localName, prefix, document),
-            textinput: DOMRefCell::new(TextInput::new(Lines::Multiple, DOMString::new(), chan, None)),
+            textinput: DOMRefCell::new(TextInput::new(
+                    Lines::Multiple, DOMString::new(), chan, None, SelectionDirection::None)),
             value_changed: Cell::new(false),
         }
     }
@@ -216,6 +217,48 @@ impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
     fn Labels(&self) -> Root<NodeList> {
         self.upcast::<HTMLElement>().labels()
     }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectiondirection
+    fn SetSelectionDirection(&self, direction: DOMString) {
+        self.textinput.borrow_mut().selection_direction = SelectionDirection::from(direction);
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectiondirection
+    fn SelectionDirection(&self) -> DOMString {
+        DOMString::from(self.textinput.borrow().selection_direction)
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionend
+    fn SetSelectionEnd(&self, end: u32) {
+        let selection_start = self.SelectionStart();
+        self.textinput.borrow_mut().set_selection_range(selection_start, end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionend
+    fn SelectionEnd(&self) -> u32 {
+        self.textinput.borrow().get_absolute_insertion_point() as u32
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
+    fn SetSelectionStart(&self, start: u32) {
+        let selection_end = self.SelectionEnd();
+        self.textinput.borrow_mut().set_selection_range(start, selection_end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
+    fn SelectionStart(&self) -> u32 {
+        self.textinput.borrow().get_selection_start()
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-setselectionrange
+    fn SetSelectionRange(&self, start: u32, end: u32, direction: Option<DOMString>) {
+        let direction = direction.map_or(SelectionDirection::None, |d| SelectionDirection::from(d));
+        self.textinput.borrow_mut().selection_direction = direction;
+        self.textinput.borrow_mut().set_selection_range(start, end);
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+    }
 }
 
 

components/script/dom/webidls/HTMLTextAreaElement.webidl

@@ -38,11 +38,11 @@ interface HTMLTextAreaElement : HTMLElement {
   readonly attribute NodeList labels;
 
   //void select();
-  //         attribute unsigned long selectionStart;
-  //         attribute unsigned long selectionEnd;
-  //         attribute DOMString selectionDirection;
+           attribute unsigned long selectionStart;
+           attribute unsigned long selectionEnd;
+           attribute DOMString selectionDirection;
   //void setRangeText(DOMString replacement);
   //void setRangeText(DOMString replacement, unsigned long start, unsigned long end,
   //                  optional SelectionMode selectionMode = "preserve");
-  //void setSelectionRange(unsigned long start, unsigned long end, optional DOMString direction);
+  void setSelectionRange(unsigned long start, unsigned long end, optional DOMString direction);
 };

components/script/textinput.rs

@@ -21,6 +21,33 @@ pub enum Selection {
     NotSelected
 }
 
+#[derive(JSTraceable, PartialEq, Copy, Clone, HeapSizeOf)]
+pub enum SelectionDirection {
+    Forward,
+    Backward,
+    None,
+}
+
+impl From<DOMString> for SelectionDirection {
+    fn from(direction: DOMString) -> SelectionDirection {
+        match direction.as_ref() {
+            "forward" => SelectionDirection::Forward,
+            "backward" => SelectionDirection::Backward,
+            _ => SelectionDirection::None,
+        }
+    }
+}
+
+impl From<SelectionDirection> for DOMString {
+    fn from(direction: SelectionDirection) -> DOMString {
+        match direction {
+            SelectionDirection::Forward => DOMString::from("forward"),
+            SelectionDirection::Backward => DOMString::from("backward"),
+            SelectionDirection::None => DOMString::from("none"),
+        }
+    }
+}
+
 #[derive(JSTraceable, Copy, Clone, HeapSizeOf, PartialEq)]
 pub struct TextPoint {
     /// 0-based line number
@@ -45,7 +72,8 @@ pub struct TextInput<T: ClipboardProvider> {
     /// The maximum number of UTF-16 code units this text input is allowed to hold.
     ///
     /// https://html.spec.whatwg.org/multipage/#attr-fe-maxlength
-    pub max_length: Option<usize>
+    pub max_length: Option<usize>,
+    pub selection_direction: SelectionDirection,
 }
 
 /// Resulting action to be taken by the owner of a text input that is handling an event.
@@ -138,14 +166,17 @@ fn len_of_first_n_code_units(text: &str, n: usize) -> usize {
 
 impl<T: ClipboardProvider> TextInput<T> {
     /// Instantiate a new text input control
-    pub fn new(lines: Lines, initial: DOMString, clipboard_provider: T, max_length: Option<usize>) -> TextInput<T> {
+    pub fn new(lines: Lines, initial: DOMString,
+               clipboard_provider: T, max_length: Option<usize>,
+               selection_direction: SelectionDirection) -> TextInput<T> {
         let mut i = TextInput {
             lines: vec!(),
             edit_point: Default::default(),
             selection_begin: None,
             multiline: lines == Lines::Multiple,
             clipboard_provider: clipboard_provider,
-            max_length: max_length
+            max_length: max_length,
+            selection_direction: selection_direction,
         };
         i.set_content(initial);
         i
@@ -607,4 +638,32 @@ impl<T: ClipboardProvider> TextInput<T> {
             line: line, index: index
         }
     }
+
+    pub fn set_selection_range(&mut self, start: u32, end: u32) {
+        let mut start = start as usize;
+        let mut end = end as usize;
+        let text_end = self.get_content().len();
+
+        if start > text_end {
+            start = text_end;
+        } else if end > text_end {
+            end = text_end;
+        } else if start >= end {
+            start = end;
+        }
+
+        self.selection_begin = Some(self.get_text_point_for_absolute_point(start));
+        self.edit_point = self.get_text_point_for_absolute_point(end);
+    }
+
+    pub fn get_selection_start(&self) -> u32 {
+        let selection_start = match self.selection_begin {
+            Some(selection_begin_point) => {
+                self.get_absolute_point_for_text_point(&selection_begin_point)
+            },
+            None => self.get_absolute_insertion_point()
+        };
+
+        selection_start as u32
+    }
 }