AK+Everywhere: Use mostly StringView in LexicalPath

This changes the m_parts, m_dirname, m_basename, m_title and m_extension
member variables to StringViews onto the m_string String. It also
removes the m_is_absolute member in favour of computing if a path is
absolute in the is_absolute() getter. Due to this, the canonicalize()
method has been completely rewritten.

The parts() getter still returns a Vector<String>, although it is no
longer a const reference as m_parts is no longer a Vector<String>.
Rather, it is constructed from the StringViews in m_parts upon request.
The parts_view() getter has been added, which returns Vector<StringView>
const&. Most previous users of parts() have been changed to use
parts_view(), except where Strings are required.

Due to this change, it's is now no longer allow to create temporary
LexicalPath objects to call the dirname, basename, title, or extension
getters on them because the returned StringViews will point to possible
freed memory.

1 files changed, 2 insertions, 2 deletions

diff --git a/Userland/Libraries/LibGUI/EmojiInputDialog.cpp b/Userland/Libraries/LibGUI/EmojiInputDialog.cpp
index 098a2ce1ab..7a25e701c3 100644
--- a/Userland/Libraries/LibGUI/EmojiInputDialog.cpp
+++ b/Userland/Libraries/LibGUI/EmojiInputDialog.cpp
@@ -26,10 +26,10 @@ static Vector<u32> supported_emoji_code_points()
         auto lexical_path = LexicalPath(filename);
         if (lexical_path.extension() != "png")
             continue;
-        auto basename = lexical_path.basename();
+        auto& basename = lexical_path.basename();
         if (!basename.starts_with("U+"))
             continue;
-        u32 code_point = strtoul(basename.characters() + 2, nullptr, 16);
+        u32 code_point = strtoul(basename.to_string().characters() + 2, nullptr, 16);
         code_points.append(code_point);
     }
     return code_points;