AK+Userland: Remove nullability feature for the ByteBuffer type

Nobody seems to use this particular feature, in fact there were some
bugs which were uncovered by removing operator bool.

16 files changed, 12 insertions, 36 deletions

diff --git a/AK/ByteBuffer.h b/AK/ByteBuffer.h
index 3b188695b3..f3b299e586 100644
--- a/AK/ByteBuffer.h
+++ b/AK/ByteBuffer.h
@@ -28,7 +28,6 @@ public:
     {
         grow(other.size());
         VERIFY(m_size == other.size());
-        VERIFY(!m_is_null);
         __builtin_memcpy(data(), other.data(), other.size());
     }
 
@@ -96,10 +95,6 @@ public:
 
     bool operator!=(ByteBuffer const& other) const { return !(*this == other); }
 
-    operator bool() const { return !is_null(); }
-    bool operator!() const { return is_null(); }
-    [[nodiscard]] bool is_null() const { return m_is_null; }
-
     [[nodiscard]] u8& operator[](size_t i)
     {
         VERIFY(i < m_size);
@@ -152,7 +147,6 @@ public:
 
     void grow(size_t new_size)
     {
-        m_is_null = false;
         if (new_size <= m_size)
             return;
         if (new_size <= capacity()) {
@@ -208,20 +202,17 @@ private:
     ByteBuffer(size_t size)
     {
         grow(size);
-        VERIFY(!m_is_null);
         VERIFY(m_size == size);
     }
 
     void move_from(ByteBuffer&& other)
     {
-        m_is_null = other.m_is_null;
         m_size = other.m_size;
         if (other.m_size > inline_capacity) {
             m_outline_buffer = other.m_outline_buffer;
             m_outline_capacity = other.m_outline_capacity;
         } else
             __builtin_memcpy(m_inline_buffer, other.m_inline_buffer, other.m_size);
-        other.m_is_null = true;
         other.m_size = 0;
     }
 
@@ -242,7 +233,6 @@ private:
     size_t capacity() const { return is_inline() ? inline_capacity : m_outline_capacity; }
 
     size_t m_size { 0 };
-    bool m_is_null { true };
     union {
         u8 m_inline_buffer[inline_capacity];
         struct {
diff --git a/AK/String.h b/AK/String.h
index 621ff92dc1..ff729558cd 100644
--- a/AK/String.h
+++ b/AK/String.h
@@ -240,8 +240,6 @@ public:
     template<typename BufferType>
     [[nodiscard]] static String copy(const BufferType& buffer, ShouldChomp should_chomp = NoChomp)
     {
-        if (buffer.is_null())
-            return {};
         if (buffer.is_empty())
             return empty();
         return String((const char*)buffer.data(), buffer.size(), should_chomp);
diff --git a/AK/Vector.h b/AK/Vector.h
index 7acc9bdd15..55cf46ca2a 100644
--- a/AK/Vector.h
+++ b/AK/Vector.h
@@ -150,8 +150,6 @@ public:
         return false;
     }
 
-    // NOTE: Vector::is_null() exists for the benefit of String::copy().
-    bool is_null() const { return false; }
     bool is_empty() const { return size() == 0; }
     ALWAYS_INLINE size_t size() const { return m_size; }
     size_t capacity() const { return m_capacity; }
diff --git a/Userland/Applications/HexEditor/HexEditor.cpp b/Userland/Applications/HexEditor/HexEditor.cpp
index 31177674e3..021eaac965 100644
--- a/Userland/Applications/HexEditor/HexEditor.cpp
+++ b/Userland/Applications/HexEditor/HexEditor.cpp
@@ -563,11 +563,6 @@ int HexEditor::find_and_highlight(ByteBuffer& needle, int start)
     if (m_buffer.is_empty())
         return -1;
 
-    if (needle.is_null()) {
-        dbgln("needle is null");
-        return -1;
-    }
-
     auto raw_offset = memmem(m_buffer.data() + start, m_buffer.size(), needle.data(), needle.size());
     if (raw_offset == NULL)
         return -1;
diff --git a/Userland/Applications/HexEditor/HexEditorWidget.cpp b/Userland/Applications/HexEditor/HexEditorWidget.cpp
index b328e8533c..2be3aed1ce 100644
--- a/Userland/Applications/HexEditor/HexEditorWidget.cpp
+++ b/Userland/Applications/HexEditor/HexEditorWidget.cpp
@@ -189,7 +189,7 @@ void HexEditorWidget::initialize_menubar(GUI::Menubar& menubar)
     }));
 
     edit_menu.add_action(GUI::Action::create("Find &Next", { Mod_None, Key_F3 }, Gfx::Bitmap::load_from_file("/res/icons/16x16/find-next.png"), [&](const GUI::Action&) {
-        if (m_search_text.is_empty() || m_search_buffer.is_empty() || m_search_buffer.is_null()) {
+        if (m_search_text.is_empty() || m_search_buffer.is_empty()) {
             GUI::MessageBox::show(window(), "Nothing to search for", "Not found", GUI::MessageBox::Type::Warning);
             return;
         }
diff --git a/Userland/Libraries/LibCore/IODevice.cpp b/Userland/Libraries/LibCore/IODevice.cpp
index cde5c55548..6dd7e3dc9c 100644
--- a/Userland/Libraries/LibCore/IODevice.cpp
+++ b/Userland/Libraries/LibCore/IODevice.cpp
@@ -33,8 +33,6 @@ const char* IODevice::error_string() const
 int IODevice::read(u8* buffer, int length)
 {
     auto read_buffer = read(length);
-    if (read_buffer.is_null())
-        return 0;
     memcpy(buffer, read_buffer.data(), length);
     return read_buffer.size();
 }
@@ -151,8 +149,6 @@ ByteBuffer IODevice::read_all()
         }
         data.append((const u8*)read_buffer, nread);
     }
-    if (data.is_empty())
-        return {};
     return ByteBuffer::copy(data.data(), data.size());
 }
 
diff --git a/Userland/Libraries/LibGemini/Job.cpp b/Userland/Libraries/LibGemini/Job.cpp
index e7c2f20eca..bd0dfa5db3 100644
--- a/Userland/Libraries/LibGemini/Job.cpp
+++ b/Userland/Libraries/LibGemini/Job.cpp
@@ -110,7 +110,7 @@ void Job::on_socket_connected()
             auto read_size = 64 * KiB;
 
             auto payload = receive(read_size);
-            if (!payload) {
+            if (payload.is_empty()) {
                 if (eof()) {
                     finish_up();
                     return IterationDecision::Break;
diff --git a/Userland/Libraries/LibHTTP/Job.cpp b/Userland/Libraries/LibHTTP/Job.cpp
index 6ead5fad10..bed513576b 100644
--- a/Userland/Libraries/LibHTTP/Job.cpp
+++ b/Userland/Libraries/LibHTTP/Job.cpp
@@ -283,7 +283,7 @@ void Job::on_socket_connected()
             }
 
             auto payload = receive(read_size);
-            if (!payload) {
+            if (payload.is_empty()) {
                 if (eof()) {
                     finish_up();
                     return IterationDecision::Break;
diff --git a/Userland/Libraries/LibTLS/ClientHandshake.cpp b/Userland/Libraries/LibTLS/ClientHandshake.cpp
index c012df5bc7..ebe9949abc 100644
--- a/Userland/Libraries/LibTLS/ClientHandshake.cpp
+++ b/Userland/Libraries/LibTLS/ClientHandshake.cpp
@@ -474,9 +474,7 @@ ssize_t TLSv12::handle_payload(ReadonlyBytes vbuffer)
             }
             break;
         case Finished:
-            if (m_context.cached_handshake) {
-                m_context.cached_handshake.clear();
-            }
+            m_context.cached_handshake.clear();
             if (m_context.handshake_messages[10] >= 1) {
                 dbgln("unexpected finished message");
                 payload_res = (i8)Error::UnexpectedMessage;
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/DeprecatedCSSParser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/DeprecatedCSSParser.cpp
index 83366ae1f7..244ba6c0cc 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/DeprecatedCSSParser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/DeprecatedCSSParser.cpp
@@ -431,7 +431,7 @@ public:
         if (type != CSS::Selector::SimpleSelector::Type::Universal) {
             while (is_valid_selector_char(peek()))
                 buffer.append(consume_one());
-            PARSE_VERIFY(!buffer.is_null());
+            PARSE_VERIFY(!buffer.is_empty());
         }
 
         auto value = String::copy(buffer);
diff --git a/Userland/Libraries/LibWeb/Loader/Resource.h b/Userland/Libraries/LibWeb/Loader/Resource.h
index 1575040ba0..1fca238e3e 100644
--- a/Userland/Libraries/LibWeb/Loader/Resource.h
+++ b/Userland/Libraries/LibWeb/Loader/Resource.h
@@ -42,7 +42,7 @@ public:
     bool is_failed() const { return m_failed; }
     const String& error() const { return m_error; }
 
-    bool has_encoded_data() const { return !m_encoded_data.is_null(); }
+    bool has_encoded_data() const { return !m_encoded_data.is_empty(); }
 
     const URL& url() const { return m_request.url(); }
     const ByteBuffer& encoded_data() const { return m_encoded_data; }
diff --git a/Userland/Libraries/LibWeb/XHR/XMLHttpRequest.cpp b/Userland/Libraries/LibWeb/XHR/XMLHttpRequest.cpp
index baa68b4727..250f22fc39 100644
--- a/Userland/Libraries/LibWeb/XHR/XMLHttpRequest.cpp
+++ b/Userland/Libraries/LibWeb/XHR/XMLHttpRequest.cpp
@@ -47,7 +47,7 @@ void XMLHttpRequest::fire_progress_event(const String& event_name, u64 transmitt
 
 String XMLHttpRequest::response_text() const
 {
-    if (m_response_object.is_null())
+    if (m_response_object.is_empty())
         return {};
     return String::copy(m_response_object);
 }
diff --git a/Userland/Services/FileOperation/main.cpp b/Userland/Services/FileOperation/main.cpp
index 632f7e721c..44919a9a5f 100644
--- a/Userland/Services/FileOperation/main.cpp
+++ b/Userland/Services/FileOperation/main.cpp
@@ -143,7 +143,7 @@ int perform_copy(const String& source, const String& destination)
         while (true) {
             print_progress();
             auto buffer = source_file.read(65536);
-            if (buffer.is_null())
+            if (buffer.is_empty())
                 break;
             if (!destination_file.write(buffer)) {
                 report_warning(String::formatted("Failed to write to destination file: {}", destination_file.error_string()));
diff --git a/Userland/Services/LookupServer/MulticastDNS.cpp b/Userland/Services/LookupServer/MulticastDNS.cpp
index 31131c2a46..268c15ac04 100644
--- a/Userland/Services/LookupServer/MulticastDNS.cpp
+++ b/Userland/Services/LookupServer/MulticastDNS.cpp
@@ -168,7 +168,7 @@ Vector<DNSAnswer> MulticastDNS::lookup(const DNSName& name, DNSRecordType record
         }
 
         auto buffer = receive(1024);
-        if (!buffer)
+        if (buffer.is_empty())
             return {};
         auto optional_packet = DNSPacket::from_raw_packet(buffer.data(), buffer.size());
         if (!optional_packet.has_value()) {
diff --git a/Userland/Services/WebServer/Client.cpp b/Userland/Services/WebServer/Client.cpp
index bdde301e5d..49462bba66 100644
--- a/Userland/Services/WebServer/Client.cpp
+++ b/Userland/Services/WebServer/Client.cpp
@@ -41,7 +41,7 @@ void Client::start()
 {
     m_socket->on_ready_to_read = [this] {
         auto raw_request = m_socket->read_all();
-        if (raw_request.is_null()) {
+        if (raw_request.is_empty()) {
             die();
             return;
         }
diff --git a/Userland/Utilities/du.cpp b/Userland/Utilities/du.cpp
index 038b150d58..fc1ea7acf6 100644
--- a/Userland/Utilities/du.cpp
+++ b/Userland/Utilities/du.cpp
@@ -106,7 +106,8 @@ int parse_args(int argc, char** argv, Vector<String>& files, DuOption& du_option
         auto file = Core::File::construct(exclude_from);
         bool success = file->open(Core::OpenMode::ReadOnly);
         VERIFY(success);
-        if (const auto buff = file->read_all()) {
+        const auto buff = file->read_all();
+        if (!buff.is_empty()) {
             String patterns = String::copy(buff, Chomp);
             du_option.excluded_patterns.append(patterns.split('\n'));
         }