Support the select() method on input/textarea

Issue #19171

components/script/dom/htmlinputelement.rs

@@ -417,6 +417,31 @@ impl TextControl for HTMLInputElement {
             _ => false
         }
     }
+
+    // https://html.spec.whatwg.org/multipage/#concept-input-apply
+    //
+    // Defines input types to which the select() IDL method applies. These are a superset of the
+    // types for which selection_api_applies() returns true.
+    //
+    // Types omitted which could theoretically be included if they were
+    // rendered as a text control: file
+    fn has_selectable_text(&self) -> bool {
+        match self.input_type() {
+            InputType::Text | InputType::Search | InputType::Url
+            | InputType::Tel | InputType::Password | InputType::Email
+            | InputType::Date | InputType::Month | InputType::Week
+            | InputType::Time | InputType::DatetimeLocal | InputType::Number
+            | InputType::Color => {
+                true
+            }
+
+            InputType::Button | InputType::Checkbox | InputType::File
+            | InputType::Hidden | InputType::Image | InputType::Radio
+            | InputType::Range | InputType::Reset | InputType::Submit => {
+                false
+            }
+        }
+    }
 }
 
 impl HTMLInputElementMethods for HTMLInputElement {
@@ -687,6 +712,11 @@ impl HTMLInputElementMethods for HTMLInputElement {
         }
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-select
+    fn Select(&self) {
+        self.dom_select(); // defined in TextControl trait
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
     fn GetSelectionStart(&self) -> Option<u32> {
         self.get_dom_selection_start()

components/script/dom/htmltextareaelement.rs

@@ -152,6 +152,10 @@ impl TextControl for HTMLTextAreaElement {
     fn selection_api_applies(&self) -> bool {
         true
     }
+
+    fn has_selectable_text(&self) -> bool {
+        true
+    }
 }
 
 impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
@@ -266,6 +270,11 @@ impl HTMLTextAreaElementMethods for HTMLTextAreaElement {
         self.upcast::<HTMLElement>().labels()
     }
 
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-select
+    fn Select(&self) {
+        self.dom_select(); // defined in TextControl trait
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
     fn GetSelectionStart(&self) -> Option<u32> {
         self.get_dom_selection_start()

components/script/dom/textcontrol.rs

@@ -15,6 +15,18 @@ use textinput::{SelectionDirection, TextInput};
 pub trait TextControl: DerivedFrom<EventTarget> + DerivedFrom<Node> {
     fn textinput(&self) -> &DomRefCell<TextInput<ScriptToConstellationChan>>;
     fn selection_api_applies(&self) -> bool;
+    fn has_selectable_text(&self) -> bool;
+
+    // https://html.spec.whatwg.org/multipage/#dom-textarea/input-select
+    fn dom_select(&self) {
+        // Step 1
+        if !self.has_selectable_text() {
+            return;
+        }
+
+        // Step 2
+        self.set_selection_range(Some(0), Some(u32::max_value()), None);
+    }
 
     // https://html.spec.whatwg.org/multipage/#dom-textarea/input-selectionstart
     fn get_dom_selection_start(&self) -> Option<u32> {

components/script/dom/webidls/HTMLInputElement.webidl

@@ -89,7 +89,7 @@ interface HTMLInputElement : HTMLElement {
 
   readonly attribute NodeList labels;
 
-  //void select();
+  void select();
   [SetterThrows]
            attribute unsigned long? selectionStart;
   [SetterThrows]

components/script/dom/webidls/HTMLTextAreaElement.webidl

@@ -50,7 +50,7 @@ interface HTMLTextAreaElement : HTMLElement {
 
   readonly attribute NodeList labels;
 
-  // void select();
+  void select();
   [SetterThrows]
            attribute unsigned long? selectionStart;
   [SetterThrows]