LibJS: Implement indexed access for StringObject

abyesilyurt · May 1, 2020 · 1ba2e67 · 1ba2e67
1 parent a81bce8
commit 1ba2e67
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Showing 2 changed files with 27 additions and 0 deletions.
diff --git a/Libraries/LibJS/Runtime/Object.cpp b/Libraries/LibJS/Runtime/Object.cpp
@@ -272,6 +272,12 @@ Value Object::get_by_index(i32 property_index) const
 
  const Object* object = this;
  while (object) {
+ if (is_string_object()) {
+ auto& string = static_cast<const StringObject*>(this)->primitive_string().string();
+ if (property_index < (i32)string.length())
+ return js_string(heap(), string.substring(property_index, 1));
+ return js_undefined();
+ }
  if (static_cast<size_t>(property_index) < object->m_elements.size()) {
  auto value = object->m_elements[property_index];
  if (value.is_empty())
@@ -397,6 +403,8 @@ bool Object::has_own_property(const FlyString& property_name) const
  bool ok;
  i32 property_index = property_name.to_int(ok);
  if (ok && property_index >= 0) {
+ if (is_string_object())
+ return property_index < (i32)static_cast<const StringObject*>(this)->primitive_string().string().length();
  if (static_cast<size_t>(property_index) >= m_elements.size())
  return false;
  return !m_elements[property_index].is_empty();

diff --git a/Libraries/LibJS/Tests/indexed-access-string-object.js b/Libraries/LibJS/Tests/indexed-access-string-object.js
@@ -0,0 +1,19 @@
+load("test-common.js");
+
+try {
+ var s = "foo";
+ assert(s[0] === "f");
+ assert(s[1] === "o");
+ assert(s[2] === "o");
+ assert(s[3] === undefined);
+
+ var o = new String("bar");
+ assert(o[0] === "b");
+ assert(o[1] === "a");
+ assert(o[2] === "r");
+ assert(o[3] === undefined);
+
+ console.log("PASS");
+} catch (e) {
+ console.log("FAIL: " + e);
+}