servo: Merge #19963 - Correct default SelectionStart and SelectionEnd (from paavininanda:Issue#19958); r=<try>

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---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] Added unit tests and wpt for these changes
- [x] These changes fix #19958

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Source-Repo: https://github.com/servo/servo
Source-Revision: 62e1fc7899c2b0210dd24044d388b43ae80c276c

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 148314440b92a4f50ef93e97133ada5afe168ec1

servo/components/script/dom/htmlformelement.rs

@@ -651,7 +651,7 @@ impl HTMLFormElement {
                     child.downcast::<HTMLSelectElement>().unwrap().reset();
                 }
                 NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLTextAreaElement)) => {
-                    child.downcast::<HTMLTextAreaElement>().unwrap().reset();
+                    child.downcast::<HTMLTextAreaElement>().unwrap().reset(true);
                 }
                 NodeTypeId::Element(ElementTypeId::HTMLElement(HTMLElementTypeId::HTMLOutputElement)) => {
                     // Unimplemented

servo/components/script/dom/htmlinputelement.rs

@@ -552,36 +552,7 @@ impl HTMLInputElementMethods for HTMLInputElement {
 
     // https://html.spec.whatwg.org/multipage/#dom-input-value
     fn SetValue(&self, value: DOMString) -> ErrorResult {
-        match self.value_mode() {
-            ValueMode::Value => {
-                // Steps 1-2.
-                let old_value = mem::replace(self.textinput.borrow_mut().single_line_content_mut(), value);
-                // Step 3.
-                self.value_dirty.set(true);
-                // Step 4.
-                self.sanitize_value();
-                // Step 5.
-                if *self.textinput.borrow().single_line_content() != old_value {
-                    self.textinput.borrow_mut().clear_selection_to_limit(Direction::Forward);
-                }
-            }
-            ValueMode::Default |
-            ValueMode::DefaultOn => {
-                self.upcast::<Element>().set_string_attribute(&local_name!("value"), value);
-            }
-            ValueMode::Filename => {
-                if value.is_empty() {
-                    let window = window_from_node(self);
-                    let fl = FileList::new(&window, vec![]);
-                    self.filelist.set(Some(&fl));
-                } else {
-                    return Err(Error::InvalidState);
-                }
-            }
-        }
-
-        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
-        Ok(())
+        self.update_text_contents(value, true)
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-input-defaultvalue
@@ -937,7 +908,7 @@ impl HTMLInputElement {
             _ => ()
         }
 
-        self.SetValue(self.DefaultValue())
+        self.update_text_contents(self.DefaultValue(), true)
             .expect("Failed to reset input value to default.");
         self.value_dirty.set(false);
         self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
@@ -1065,7 +1036,7 @@ impl HTMLInputElement {
                     let content = textinput.single_line_content_mut();
                     content.make_ascii_lowercase();
                 } else {
-                    textinput.set_content("#000000".into());
+                    textinput.set_content("#000000".into(), true);
                 }
             }
             InputType::Time => {
@@ -1103,6 +1074,41 @@ impl HTMLInputElement {
     fn selection(&self) -> TextControlSelection<Self> {
         TextControlSelection::new(&self, &self.textinput)
     }
+
+    fn update_text_contents(&self, value: DOMString, update_text_cursor: bool) -> ErrorResult {
+        match self.value_mode() {
+            ValueMode::Value => {
+                // Steps 1-2.
+                let old_value = mem::replace(self.textinput.borrow_mut().single_line_content_mut(), value);
+                // Step 3.
+                self.value_dirty.set(true);
+                // Step 4.
+                if update_text_cursor {
+                    self.sanitize_value();
+                }
+                // Step 5.
+                if *self.textinput.borrow().single_line_content() != old_value {
+                    self.textinput.borrow_mut().clear_selection_to_limit(Direction::Forward, update_text_cursor);
+                }
+            }
+            ValueMode::Default |
+            ValueMode::DefaultOn => {
+                self.upcast::<Element>().set_string_attribute(&local_name!("value"), value);
+            }
+            ValueMode::Filename => {
+                if value.is_empty() {
+                    let window = window_from_node(self);
+                    let fl = FileList::new(&window, vec![]);
+                    self.filelist.set(Some(&fl));
+                } else {
+                    return Err(Error::InvalidState);
+                }
+            }
+        }
+
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+        Ok(())
+    }
 }
 
 impl VirtualMethods for HTMLInputElement {
@@ -1112,7 +1118,6 @@ impl VirtualMethods for HTMLInputElement {
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
         self.super_type().unwrap().attribute_mutated(attr, mutation);
-
         match attr.local_name() {
             &local_name!("disabled") => {
                 let disabled_state = match mutation {
@@ -1214,7 +1219,7 @@ impl VirtualMethods for HTMLInputElement {
 
                         // Steps 7-9
                         if !previously_selectable && self.selection_api_applies() {
-                            self.textinput.borrow_mut().clear_selection_to_limit(Direction::Backward);
+                            self.textinput.borrow_mut().clear_selection_to_limit(Direction::Backward, true);
                         }
                     },
                     AttributeMutation::Removed => {
@@ -1236,7 +1241,7 @@ impl VirtualMethods for HTMLInputElement {
             &local_name!("value") if !self.value_dirty.get() => {
                 let value = mutation.new_value(attr).map(|value| (**value).to_owned());
                 self.textinput.borrow_mut().set_content(
-                    value.map_or(DOMString::new(), DOMString::from));
+                    value.map_or(DOMString::new(), DOMString::from), true);
                 self.sanitize_value();
                 self.update_placeholder_shown_state();
             },

servo/components/script/dom/htmltextareaelement.rs

@@ -233,7 +233,7 @@ impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
         // if the element's dirty value flag is false, then the element's
         // raw value must be set to the value of the element's textContent IDL attribute
         if !self.value_dirty.get() {
-            self.reset();
+            self.reset(false);
         }
     }
 
@@ -244,26 +244,7 @@ impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea-value
     fn SetValue(&self, value: DOMString) {
-        let mut textinput = self.textinput.borrow_mut();
-
-        // Step 1
-        let old_value = textinput.get_content();
-        let old_selection = textinput.selection_origin;
-
-        // Step 2
-        textinput.set_content(value);
-
-        // Step 3
-        self.value_dirty.set(true);
-
-        if old_value != textinput.get_content() {
-            // Step 4
-            textinput.clear_selection_to_limit(Direction::Forward);
-        } else {
-            textinput.selection_origin = old_selection;
-        }
-
-        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+        self.update_text_contents(value, true);
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-lfe-labels
@@ -325,9 +306,9 @@ impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
 
 
 impl HTMLTextAreaElement {
-    pub fn reset(&self) {
+    pub fn reset(&self,  update_text_cursor: bool) {
         // https://html.spec.whatwg.org/multipage/#the-textarea-element:concept-form-reset-control
-        self.SetValue(self.DefaultValue());
+        self.update_text_contents(self.DefaultValue(), update_text_cursor);
         self.value_dirty.set(false);
     }
 
@@ -335,6 +316,30 @@ impl HTMLTextAreaElement {
     fn selection(&self) -> TextControlSelection<Self> {
         TextControlSelection::new(&self, &self.textinput)
     }
+
+    // Helper function to check if text_cursor is to be updated or not
+    fn update_text_contents(&self, value: DOMString, update_text_cursor: bool) {
+        let mut textinput = self.textinput.borrow_mut();
+
+        // Step 1
+        let old_value = textinput.get_content();
+        let old_selection = textinput.selection_origin;
+
+        // Step 2
+        textinput.set_content(value, update_text_cursor);
+
+        // Step 3
+        self.value_dirty.set(true);
+
+        if old_value != textinput.get_content() {
+            // Step 4
+            textinput.clear_selection_to_limit(Direction::Forward, update_text_cursor);
+        } else {
+            textinput.selection_origin = old_selection;
+        }
+
+        self.upcast::<Node>().dirty(NodeDamage::OtherNodeDamage);
+    }
 }
 
 
@@ -427,7 +432,7 @@ impl VirtualMethods for HTMLTextAreaElement {
             s.children_changed(mutation);
         }
         if !self.value_dirty.get() {
-            self.reset();
+            self.reset(false);
         }
     }
 
@@ -478,7 +483,7 @@ impl VirtualMethods for HTMLTextAreaElement {
         self.super_type().unwrap().pop();
 
         // https://html.spec.whatwg.org/multipage/#the-textarea-element:stack-of-open-elements
-        self.reset();
+        self.reset(false);
     }
 }
 

servo/components/script/textinput.rs

@@ -171,7 +171,7 @@ impl<T: ClipboardProvider> TextInput<T> {
             min_length: min_length,
             selection_direction: selection_direction,
         };
-        i.set_content(initial);
+        i.set_content(initial, false);
         i
     }
 
@@ -411,9 +411,7 @@ impl<T: ClipboardProvider> TextInput<T> {
             return;
         }
 
-
         let col = self.lines[self.edit_point.line][..self.edit_point.index].chars().count();
-
         self.edit_point.line = target_line as usize;
         self.edit_point.index = len_of_first_n_chars(&self.lines[self.edit_point.line], col);
         self.assert_ok_selection();
@@ -533,9 +531,9 @@ impl<T: ClipboardProvider> TextInput<T> {
     }
 
     /// Remove the current selection and set the edit point to the end of the content.
-    pub fn clear_selection_to_limit(&mut self, direction: Direction) {
+    pub fn clear_selection_to_limit(&mut self, direction: Direction, update_text_cursor: bool) {
         self.clear_selection();
-        self.adjust_horizontal_to_limit(direction, Selection::NotSelected);
+        self.adjust_horizontal_to_limit(direction, Selection::NotSelected, update_text_cursor);
     }
 
     pub fn adjust_horizontal_by_word(&mut self, direction: Direction, select: Selection) {
@@ -627,18 +625,20 @@ impl<T: ClipboardProvider> TextInput<T> {
         self.perform_horizontal_adjustment(shift, select);
     }
 
-    pub fn adjust_horizontal_to_limit(&mut self, direction: Direction, select: Selection) {
+    pub fn adjust_horizontal_to_limit(&mut self, direction: Direction, select: Selection, update_text_cursor: bool) {
         if self.adjust_selection_for_horizontal_change(direction, select) {
             return
         }
-        match direction {
-            Direction::Backward => {
-                self.edit_point.line = 0;
-                self.edit_point.index = 0;
-            },
-            Direction::Forward => {
-                self.edit_point.line = &self.lines.len() - 1;
-                self.edit_point.index = (&self.lines[&self.lines.len() - 1]).len();
+        if update_text_cursor {
+            match direction {
+                Direction::Backward => {
+                    self.edit_point.line = 0;
+                    self.edit_point.index = 0;
+                },
+                Direction::Forward => {
+                    self.edit_point.line = &self.lines.len() - 1;
+                    self.edit_point.index = (&self.lines[&self.lines.len() - 1]).len();
+                }
             }
         }
     }
@@ -728,12 +728,12 @@ impl<T: ClipboardProvider> TextInput<T> {
             },
             #[cfg(target_os = "macos")]
             (None, Key::Up) if mods.contains(KeyModifiers::SUPER) => {
-                self.adjust_horizontal_to_limit(Direction::Backward, maybe_select);
+                self.adjust_horizontal_to_limit(Direction::Backward, maybe_select, true);
                 KeyReaction::RedrawSelection
             },
             #[cfg(target_os = "macos")]
             (None, Key::Down) if mods.contains(KeyModifiers::SUPER) => {
-                self.adjust_horizontal_to_limit(Direction::Forward, maybe_select);
+                self.adjust_horizontal_to_limit(Direction::Forward, maybe_select, true);
                 KeyReaction::RedrawSelection
             },
             (None, Key::Left) if mods.contains(KeyModifiers::ALT) => {
@@ -840,7 +840,7 @@ impl<T: ClipboardProvider> TextInput<T> {
 
     /// Set the current contents of the text input. If this is control supports multiple lines,
     /// any \n encountered will be stripped and force a new logical line.
-    pub fn set_content(&mut self, content: DOMString) {
+    pub fn set_content(&mut self, content: DOMString, update_text_cursor: bool) {
         self.lines = if self.multiline {
             // https://html.spec.whatwg.org/multipage/#textarea-line-break-normalisation-transformation
             content.replace("\r\n", "\n")
@@ -850,8 +850,10 @@ impl<T: ClipboardProvider> TextInput<T> {
         } else {
             vec!(content)
         };
-        self.edit_point.line = min(self.edit_point.line, self.lines.len() - 1);
-        self.edit_point.index = min(self.edit_point.index, self.current_line_length());
+        if update_text_cursor {
+            self.edit_point.line = min(self.edit_point.line, self.lines.len() - 1);
+            self.edit_point.index = min(self.edit_point.index, self.current_line_length());
+        }
         self.selection_origin = None;
         self.assert_ok_selection();
     }

servo/tests/unit/script/textinput.rs

@@ -27,7 +27,7 @@ fn test_set_content_ignores_max_length() {
         Lines::Single, DOMString::from(""), DummyClipboardContext::new(""), Some(1), None, SelectionDirection::None
     );
 
-    textinput.set_content(DOMString::from("mozilla rocks"));
+    textinput.set_content(DOMString::from("mozilla rocks"), true);
     assert_eq!(textinput.get_content(), DOMString::from("mozilla rocks"));
 }
 
@@ -492,7 +492,7 @@ fn test_textinput_set_content() {
     let mut textinput = text_input(Lines::Multiple, "abc\nde\nf");
     assert_eq!(textinput.get_content(), "abc\nde\nf");
 
-    textinput.set_content(DOMString::from("abc\nf"));
+    textinput.set_content(DOMString::from("abc\nf"), true);
     assert_eq!(textinput.get_content(), "abc\nf");
 
     assert_eq!(textinput.edit_point.line, 0);
@@ -500,7 +500,7 @@ fn test_textinput_set_content() {
     textinput.adjust_horizontal(3, Selection::Selected);
     assert_eq!(textinput.edit_point.line, 0);
     assert_eq!(textinput.edit_point.index, 3);
-    textinput.set_content(DOMString::from("de"));
+    textinput.set_content(DOMString::from("de"), true);
     assert_eq!(textinput.get_content(), "de");
     assert_eq!(textinput.edit_point.line, 0);
     assert_eq!(textinput.edit_point.index, 2);
@@ -637,6 +637,10 @@ fn test_textinput_unicode_handling() {
 fn test_selection_bounds() {
     let mut textinput = text_input(Lines::Single, "abcdef");
 
+    assert_eq!(TextPoint { line: 0, index: 0 }, textinput.selection_origin_or_edit_point());
+    assert_eq!(TextPoint { line: 0, index: 0 }, textinput.selection_start());
+    assert_eq!(TextPoint { line: 0, index: 0 }, textinput.selection_end());
+
     textinput.set_selection_range(2, 5, SelectionDirection::Forward);
     assert_eq!(TextPoint { line: 0, index: 2 }, textinput.selection_origin_or_edit_point());
     assert_eq!(TextPoint { line: 0, index: 2 }, textinput.selection_start());