Auto merge of #18262 - KiChjang:value-sanitization, r=nox

Implement value sanitization on HTMLInputElement

https://html.spec.whatwg.org/multipage/input.html#value-sanitization-algorithm

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1 files changed, 23 insertions, 0 deletions

diff --git a/components/script/dom/bindings/str.rs b/components/script/dom/bindings/str.rs
index 60b8d6183be..3667dddf92d 100644
--- a/components/script/dom/bindings/str.rs
+++ b/components/script/dom/bindings/str.rs
@@ -185,6 +185,29 @@ impl DOMString {
     pub fn bytes(&self) -> Bytes {
         self.0.bytes()
     }
+
+    /// Removes newline characters according to <https://infra.spec.whatwg.org/#strip-newlines>.
+    pub fn strip_newlines(&mut self) {
+        self.0.retain(|c| c != '\r' && c != '\n');
+    }
+
+    /// Removes leading and trailing ASCII whitespaces according to
+    /// <https://infra.spec.whatwg.org/#strip-leading-and-trailing-ascii-whitespace>.
+    pub fn strip_leading_and_trailing_ascii_whitespace(&mut self) {
+        if self.0.len() == 0 { return; }
+
+        let last_non_whitespace = match self.0.rfind(|ref c| !char::is_ascii_whitespace(c)) {
+            Some(idx) => idx + 1,
+            None => {
+                self.0.clear();
+                return;
+            }
+        };
+        let first_non_whitespace = self.0.find(|ref c| !char::is_ascii_whitespace(c)).unwrap();
+
+        self.0.truncate(last_non_whitespace);
+        let _ = self.0.splice(0..first_non_whitespace, "");
+    }
 }
 
 impl Borrow<str> for DOMString {