Adds support for input element's maxlength attr

servo/servo#7320
servo/servo#7004

components/script/dom/htmlinputelement.rs

@@ -8,8 +8,8 @@ use dom::attr::{Attr, AttrValue};
 use dom::bindings::cell::DOMRefCell;
 use dom::bindings::codegen::Bindings::AttrBinding::AttrMethods;
 use dom::bindings::codegen::Bindings::EventBinding::EventMethods;
-use dom::bindings::codegen::Bindings::HTMLInputElementBinding;
 use dom::bindings::codegen::Bindings::HTMLInputElementBinding::HTMLInputElementMethods;
+use dom::bindings::codegen::Bindings::HTMLInputElementBinding;
 use dom::bindings::codegen::Bindings::KeyboardEventBinding::KeyboardEventMethods;
 use dom::bindings::global::GlobalRef;
 use dom::bindings::inheritance::Castable;
@@ -32,6 +32,7 @@ use msg::constellation_msg::ScriptMsg as ConstellationMsg;
 use selectors::states::*;
 use std::borrow::ToOwned;
 use std::cell::Cell;
+use std::i32;
 use string_cache::Atom;
 use textinput::KeyReaction::{DispatchInput, Nothing, RedrawSelection, TriggerDefaultAction};
 use textinput::Lines::Single;
@@ -116,7 +117,7 @@ impl HTMLInputElement {
             checked_changed: Cell::new(false),
             value_changed: Cell::new(false),
             size: Cell::new(DEFAULT_INPUT_SIZE),
-            textinput: DOMRefCell::new(TextInput::new(Single, DOMString::new(), chan)),
+            textinput: DOMRefCell::new(TextInput::new(Single, DOMString::new(), chan, None)),
             activation_state: DOMRefCell::new(InputActivationState::new())
         }
     }
@@ -337,6 +338,21 @@ impl HTMLInputElementMethods for HTMLInputElement {
     // https://html.spec.whatwg.org/multipage/#dom-input-formtarget
     make_setter!(SetFormTarget, "formtarget");
 
+    // https://html.spec.whatwg.org/multipage/#dom-input-maxlength
+    fn MaxLength(&self) -> i32 {
+        match self.textinput.borrow().max_length {
+            Some(max_length) => max_length as i32,
+            None => i32::MAX
+        }
+    }
+
+    // https://html.spec.whatwg.org/multipage/#dom-input-maxlength
+    fn SetMaxLength(&self, max_length: i32) {
+        if max_length > 0 {
+            self.textinput.borrow_mut().max_length = Some(max_length as usize)
+        }
+    }
+
     // https://html.spec.whatwg.org/multipage/#dom-input-indeterminate
     fn Indeterminate(&self) -> bool {
         self.upcast::<Element>().get_state().contains(IN_INDETERMINATE_STATE)
@@ -511,6 +527,7 @@ impl VirtualMethods for HTMLInputElement {
 
     fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
         self.super_type().unwrap().attribute_mutated(attr, mutation);
+
         match attr.local_name() {
             &atom!("disabled") => {
                 let disabled_state = match mutation {
@@ -581,6 +598,18 @@ impl VirtualMethods for HTMLInputElement {
                 self.radio_group_updated(
                     mutation.new_value(attr).as_ref().map(|name| name.as_atom()));
             },
+            &atom!("maxlength") => {
+                match *attr.value() {
+                    AttrValue::Int(_, value) => {
+                        if value < 0 {
+                            self.textinput.borrow_mut().max_length = None
+                        } else {
+                            self.textinput.borrow_mut().max_length = Some(value as usize)
+                        }
+                    },
+                    _ => panic!("Expected an AttrValue::UInt"),
+                }
+            }
             &atom!("placeholder") => {
                 // FIXME(ajeffrey): Should we do in-place mutation of the placeholder?
                 let mut placeholder = self.placeholder.borrow_mut();
@@ -599,6 +628,7 @@ impl VirtualMethods for HTMLInputElement {
             &atom!("name") => AttrValue::from_atomic(value),
             &atom!("size") => AttrValue::from_limited_u32(value, DEFAULT_INPUT_SIZE),
             &atom!("type") => AttrValue::from_atomic(value),
+            &atom!("maxlength") => AttrValue::from_i32(value, i32::MAX),
             _ => self.super_type().unwrap().parse_plain_attribute(name, value),
         }
     }

components/script/dom/htmltextareaelement.rs

@@ -30,6 +30,7 @@ use script_task::ScriptTaskEventCategory::InputEvent;
 use script_task::{CommonScriptMsg, Runnable};
 use selectors::states::*;
 use std::cell::Cell;
+use std::i32;
 use string_cache::Atom;
 use textinput::{KeyReaction, Lines, TextInput};
 use util::str::DOMString;
@@ -89,6 +90,7 @@ impl<'a> RawLayoutHTMLTextAreaElementHelpers for &'a HTMLTextAreaElement {
 
 static DEFAULT_COLS: u32 = 20;
 static DEFAULT_ROWS: u32 = 2;
+static DEFAULT_MAX_LENGTH: i32 = i32::MAX;
 
 impl HTMLTextAreaElement {
     fn new_inherited(localName: DOMString,
@@ -99,7 +101,7 @@ impl HTMLTextAreaElement {
             htmlelement:
                 HTMLElement::new_inherited_with_state(IN_ENABLED_STATE,
                                                       localName, prefix, document),
-            textinput: DOMRefCell::new(TextInput::new(Lines::Multiple, DOMString::new(), chan)),
+            textinput: DOMRefCell::new(TextInput::new(Lines::Multiple, DOMString::new(), chan, None)),
             cols: Cell::new(DEFAULT_COLS),
             rows: Cell::new(DEFAULT_ROWS),
             value_changed: Cell::new(false),

components/script/dom/webidls/HTMLInputElement.webidl

@@ -25,7 +25,7 @@ interface HTMLInputElement : HTMLElement {
   //         attribute DOMString inputMode;
   //readonly attribute HTMLElement? list;
   //         attribute DOMString max;
-  //         attribute long maxLength;
+          attribute long maxLength;
   //         attribute DOMString min;
   //         attribute long minLength;
   //         attribute boolean multiple;

components/script/textinput.rs

@@ -11,6 +11,7 @@ use msg::constellation_msg::{Key, KeyModifiers};
 use std::borrow::ToOwned;
 use std::cmp::{max, min};
 use std::default::Default;
+use std::usize;
 use util::mem::HeapSizeOf;
 use util::str::DOMString;
 
@@ -41,6 +42,7 @@ pub struct TextInput<T: ClipboardProvider> {
     multiline: bool,
     #[ignore_heap_size_of = "Can't easily measure this generic type"]
     clipboard_provider: T,
+    pub max_length: Option<usize>
 }
 
 /// Resulting action to be taken by the owner of a text input that is handling an event.
@@ -107,13 +109,14 @@ fn is_printable_key(key: Key) -> bool {
 
 impl<T: ClipboardProvider> TextInput<T> {
     /// Instantiate a new text input control
-    pub fn new(lines: Lines, initial: DOMString, clipboard_provider: T) -> TextInput<T> {
+    pub fn new(lines: Lines, initial: DOMString, clipboard_provider: T, max_length: Option<usize>) -> TextInput<T> {
         let mut i = TextInput {
             lines: vec!(),
             edit_point: Default::default(),
             selection_begin: None,
             multiline: lines == Lines::Multiple,
-            clipboard_provider: clipboard_provider
+            clipboard_provider: clipboard_provider,
+            max_length: max_length
         };
         i.set_content(initial);
         i
@@ -133,7 +136,7 @@ impl<T: ClipboardProvider> TextInput<T> {
     }
 
     /// Insert a string at the current editing point
-    fn insert_string<S: Into<String>>(&mut self, s: S) {
+    pub fn insert_string<S: Into<String>>(&mut self, s: S) {
         if self.selection_begin.is_none() {
             self.selection_begin = Some(self.edit_point);
         }
@@ -170,8 +173,40 @@ impl<T: ClipboardProvider> TextInput<T> {
         })
     }
 
+    fn selection_len(&self) -> usize {
+        if let Some((begin, end)) = self.get_sorted_selection() {
+            let prefix = &self.lines[begin.line][0..begin.index];
+            let suffix = &self.lines[end.line][end.index..];
+            let lines_prefix = &self.lines[..begin.line];
+            let lines_suffix = &self.lines[end.line + 1..];
+
+            self.len() - (prefix.chars().count() +
+                          suffix.chars().count() +
+                          lines_prefix.iter().fold(0, |m, i| m + i.chars().count() + 1) +
+                          lines_suffix.iter().fold(0, |m, i| m + i.chars().count() + 1))
+        } else {
+            0
+        }
+    }
+
     pub fn replace_selection(&mut self, insert: DOMString) {
         if let Some((begin, end)) = self.get_sorted_selection() {
+            let allowed_to_insert_count = if let Some(max_length) = self.max_length {
+                let len_after_selection_replaced = self.len() - self.selection_len();
+                if len_after_selection_replaced > max_length {
+                    // If, after deleting the selection, the len is still greater than the max
+                    // length, then don't delete/insert anything
+                    return
+                }
+
+                max_length - len_after_selection_replaced
+            } else {
+                usize::MAX
+            };
+
+            let last_char_to_insert = min(allowed_to_insert_count, insert.chars().count());
+            let chars_to_insert = (&insert[0 .. last_char_to_insert]).to_owned();
+
             self.clear_selection();
 
             let new_lines = {
@@ -181,13 +216,14 @@ impl<T: ClipboardProvider> TextInput<T> {
                 let lines_suffix = &self.lines[end.line + 1..];
 
                 let mut insert_lines = if self.multiline {
-                    insert.split('\n').map(DOMString::from).collect()
+                    chars_to_insert.split('\n').map(|s| DOMString::from(s.to_owned())).collect()
                 } else {
-                    vec!(insert)
+                    vec!(DOMString::from(chars_to_insert))
                 };
 
                 // FIXME(ajeffrey): effecient append for DOMStrings
                 let mut new_line = prefix.to_owned();
+
                 new_line.push_str(&insert_lines[0]);
                 insert_lines[0] = DOMString::from(new_line);
 
@@ -434,6 +470,12 @@ impl<T: ClipboardProvider> TextInput<T> {
         }
     }
 
+    pub fn len(&self) -> usize {
+        self.lines.iter().fold(0, |m, l| {
+            m + l.len() + 1
+        }) - 1
+    }
+
     /// Get the current contents of the text input. Multiple lines are joined by \n.
     pub fn get_content(&self) -> DOMString {
         let mut content = "".to_owned();