LibCore+Everywhere: Make Core::Stream read_line() return StringView

Similar reasoning to making Core::Stream::read() return Bytes, except
that every user of read_line() creates a StringView from the result, so
let's just return one right away.

Meta/Lagom/Tools/CodeGenerators/LibTimeZone/GenerateTimeZoneData.cpp

@@ -316,8 +316,7 @@ static ErrorOr<void> parse_time_zones(StringView time_zone_path, TimeZoneData& t
     Vector<TimeZoneOffset>* last_parsed_zone = nullptr;
 
     while (TRY(file->can_read_line())) {
-        auto nread = TRY(file->read_line(buffer));
+        auto line = TRY(file->read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.trim_whitespace(TrimMode::Left).starts_with('#'))
             continue;
@@ -374,8 +373,7 @@ static ErrorOr<void> parse_time_zone_coordinates(Core::Stream::BufferedFile& fil
     Array<u8, 1024> buffer {};
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.trim_whitespace(TrimMode::Left).starts_with('#'))
             continue;

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeData.cpp

@@ -197,8 +197,7 @@ static ErrorOr<void> parse_special_casing(Core::Stream::BufferedFile& file, Unic
     Array<u8, 1024> buffer;
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#'))
             continue;
@@ -264,8 +263,7 @@ static ErrorOr<void> parse_prop_list(Core::Stream::BufferedFile& file, PropList&
     Array<u8, 1024> buffer;
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#'))
             continue;
@@ -311,8 +309,7 @@ static ErrorOr<void> parse_alias_list(Core::Stream::BufferedFile& file, PropList
     };
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#')) {
             if (line.ends_with("Properties"sv))
@@ -345,8 +342,7 @@ static ErrorOr<void> parse_name_aliases(Core::Stream::BufferedFile& file, Unicod
     Array<u8, 1024> buffer;
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#'))
             continue;
@@ -387,8 +383,7 @@ static ErrorOr<void> parse_value_alias_list(Core::Stream::BufferedFile& file, St
     };
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#'))
             continue;
@@ -421,8 +416,7 @@ static ErrorOr<void> parse_normalization_props(Core::Stream::BufferedFile& file,
     Array<u8, 1024> buffer;
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty() || line.starts_with('#'))
             continue;
@@ -518,8 +512,7 @@ static ErrorOr<void> parse_block_display_names(Core::Stream::BufferedFile& file,
 {
     Array<u8, 1024> buffer;
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
         if (line.is_empty() || line.starts_with('#'))
             continue;
 
@@ -547,8 +540,7 @@ static ErrorOr<void> parse_unicode_data(Core::Stream::BufferedFile& file, Unicod
     Array<u8, 1024> buffer;
 
     while (TRY(file.can_read_line())) {
-        auto nread = TRY(file.read_line(buffer));
+        auto line = TRY(file.read_line(buffer));
-        StringView line { buffer.data(), nread };
 
         if (line.is_empty())
             continue;

Tests/LibCore/TestLibCoreStream.cpp

@@ -426,15 +426,15 @@ TEST_CASE(buffered_long_file_read)
     auto buffer = ByteBuffer::create_uninitialized(4096).release_value();
     EXPECT(!file->seek(255, Core::Stream::SeekMode::SetPosition).is_error());
     EXPECT(file->can_read_line().release_value());
-    auto maybe_nread = file->read_line(buffer);
+    auto maybe_line = file->read_line(buffer);
-    EXPECT(!maybe_nread.is_error());
+    EXPECT(!maybe_line.is_error());
-    EXPECT_EQ(maybe_nread.value(), 4095ul); // 4095 bytes on the third line
+    EXPECT_EQ(maybe_line.value().length(), 4095ul); // 4095 bytes on the third line
 
     // Testing that buffering with seeking works properly
     EXPECT(!file->seek(365, Core::Stream::SeekMode::SetPosition).is_error());
-    auto maybe_after_seek_nread = file->read_line(buffer);
+    auto maybe_after_seek_line = file->read_line(buffer);
-    EXPECT(!maybe_after_seek_nread.is_error());
+    EXPECT(!maybe_after_seek_line.is_error());
-    EXPECT_EQ(maybe_after_seek_nread.value(), 3985ul); // 4095 - 110
+    EXPECT_EQ(maybe_after_seek_line.value().length(), 3985ul); // 4095 - 110
 }
 
 TEST_CASE(buffered_small_file_read)
@@ -456,10 +456,10 @@ TEST_CASE(buffered_small_file_read)
     auto buffer = ByteBuffer::create_uninitialized(4096).release_value();
     for (auto const& line : expected_lines) {
         VERIFY(file->can_read_line().release_value());
-        auto maybe_nread = file->read_line(buffer);
+        auto maybe_read_line = file->read_line(buffer);
-        EXPECT(!maybe_nread.is_error());
+        EXPECT(!maybe_read_line.is_error());
-        EXPECT_EQ(maybe_nread.value(), line.length());
+        EXPECT_EQ(maybe_read_line.value().length(), line.length());
-        EXPECT_EQ(StringView(buffer.span().trim(maybe_nread.value())), line);
+        EXPECT_EQ(StringView(buffer.span().trim(maybe_read_line.value().length())), line);
     }
     EXPECT(!file->can_read_line().is_error());
     EXPECT(!file->can_read_line().value());
@@ -496,13 +496,13 @@ TEST_CASE(buffered_tcp_socket_read)
 
     auto receive_buffer = ByteBuffer::create_uninitialized(64).release_value();
 
-    auto maybe_first_nread = client_socket->read_line(receive_buffer);
+    auto maybe_first_received_line = client_socket->read_line(receive_buffer);
-    EXPECT(!maybe_first_nread.is_error());
+    EXPECT(!maybe_first_received_line.is_error());
-    StringView first_received_line { receive_buffer.data(), maybe_first_nread.value() };
+    auto first_received_line = maybe_first_received_line.value();
     EXPECT_EQ(first_received_line, first_line);
 
-    auto maybe_second_nread = client_socket->read_line(receive_buffer);
+    auto maybe_second_received_line = client_socket->read_line(receive_buffer);
-    EXPECT(!maybe_second_nread.is_error());
+    EXPECT(!maybe_second_received_line.is_error());
-    StringView second_received_line { receive_buffer.data(), maybe_second_nread.value() };
+    auto second_received_line = maybe_second_received_line.value();
     EXPECT_EQ(second_received_line, second_line);
 }

Userland/Applications/Browser/main.cpp

@@ -43,8 +43,7 @@ static ErrorOr<void> load_content_filters()
     auto ad_filter_list = TRY(Core::Stream::BufferedFile::create(move(file)));
     auto buffer = TRY(ByteBuffer::create_uninitialized(4096));
     while (TRY(ad_filter_list->can_read_line())) {
-        auto length = TRY(ad_filter_list->read_line(buffer));
+        auto line = TRY(ad_filter_list->read_line(buffer));
-        StringView line { buffer.data(), length };
         if (!line.is_empty())
             Browser::g_content_filters.append(line);
     }

Userland/Applications/BrowserSettings/ContentFilterSettingsWidget.cpp

@@ -30,8 +30,7 @@ ErrorOr<void> DomainListModel::load()
     auto content_filter_list = TRY(Core::Stream::BufferedFile::create(move(file)));
     auto buffer = TRY(ByteBuffer::create_uninitialized(4096));
     while (TRY(content_filter_list->can_read_line())) {
-        auto length = TRY(content_filter_list->read_line(buffer));
+        auto line = TRY(content_filter_list->read_line(buffer));
-        StringView line { buffer.data(), length };
         dbgln("Content filter for {}", line);
         if (!line.is_empty())
             m_domain_list.append(line);

Userland/Applications/FileManager/FileOperationProgressWidget.cpp

@@ -72,13 +72,13 @@ FileOperationProgressWidget::FileOperationProgressWidget(FileOperation operation
     m_notifier = Core::Notifier::construct(helper_pipe_fd, Core::Notifier::Read);
     m_notifier->on_ready_to_read = [this] {
         auto line_buffer = ByteBuffer::create_zeroed(1 * KiB).release_value_but_fixme_should_propagate_errors();
-        auto line_length_or_error = m_helper_pipe->read_line(line_buffer.bytes());
+        auto line_or_error = m_helper_pipe->read_line(line_buffer.bytes());
-        if (line_length_or_error.is_error() || line_length_or_error.value() == 0) {
+        if (line_or_error.is_error() || line_or_error.value().is_empty()) {
             did_error("Read from pipe returned null."sv);
             return;
         }
 
-        StringView line { line_buffer.bytes().data(), line_length_or_error.value() };
+        auto line = line_or_error.release_value();
 
         auto parts = line.split_view(' ');
         VERIFY(!parts.is_empty());

Userland/Libraries/LibCore/ConfigFile.cpp

@@ -88,9 +88,7 @@ ErrorOr<void> ConfigFile::reparse()
 
     auto buffer = TRY(ByteBuffer::create_uninitialized(4096));
     while (TRY(m_file->can_read_line())) {
-        auto length = TRY(m_file->read_line(buffer));
+        auto line = TRY(m_file->read_line(buffer));
-
-        StringView line { buffer.data(), length };
         size_t i = 0;
 
         while (i < line.length() && (line[i] == ' ' || line[i] == '\t' || line[i] == '\n'))

Userland/Libraries/LibCore/Stream.h

@@ -557,10 +557,10 @@ public:
 
     // Reads into the buffer until \n is encountered.
     // The size of the Bytes object is the maximum amount of bytes that will be
-    // read. Returns the amount of bytes read.
+    // read. Returns the bytes read as a StringView.
-    ErrorOr<size_t> read_line(Bytes buffer)
+    ErrorOr<StringView> read_line(Bytes buffer)
     {
-        return TRY(read_until(buffer, "\n"sv)).size();
+        return StringView { TRY(read_until(buffer, "\n"sv)) };
     }
 
     ErrorOr<Bytes> read_until(Bytes buffer, StringView candidate)
@@ -769,7 +769,7 @@ public:
         return m_helper.stream().truncate(length);
     }
 
-    ErrorOr<size_t> read_line(Bytes buffer) { return m_helper.read_line(move(buffer)); }
+    ErrorOr<StringView> read_line(Bytes buffer) { return m_helper.read_line(move(buffer)); }
     ErrorOr<Bytes> read_until(Bytes buffer, StringView candidate) { return m_helper.read_until(move(buffer), move(candidate)); }
     template<size_t N>
     ErrorOr<Bytes> read_until_any_of(Bytes buffer, Array<StringView, N> candidates) { return m_helper.read_until_any_of(move(buffer), move(candidates)); }
@@ -790,7 +790,7 @@ private:
 
 class BufferedSocketBase : public Socket {
 public:
-    virtual ErrorOr<size_t> read_line(Bytes buffer) = 0;
+    virtual ErrorOr<StringView> read_line(Bytes buffer) = 0;
     virtual ErrorOr<Bytes> read_until(Bytes buffer, StringView candidate) = 0;
     virtual ErrorOr<bool> can_read_line() = 0;
     virtual size_t buffer_size() const = 0;
@@ -838,7 +838,7 @@ public:
     virtual ErrorOr<void> set_close_on_exec(bool enabled) override { return m_helper.stream().set_close_on_exec(enabled); }
     virtual void set_notifications_enabled(bool enabled) override { m_helper.stream().set_notifications_enabled(enabled); }
 
-    virtual ErrorOr<size_t> read_line(Bytes buffer) override { return m_helper.read_line(move(buffer)); }
+    virtual ErrorOr<StringView> read_line(Bytes buffer) override { return m_helper.read_line(move(buffer)); }
     virtual ErrorOr<Bytes> read_until(Bytes buffer, StringView candidate) override { return m_helper.read_until(move(buffer), move(candidate)); }
     template<size_t N>
     ErrorOr<Bytes> read_until_any_of(Bytes buffer, Array<StringView, N> candidates) { return m_helper.read_until_any_of(move(buffer), move(candidates)); }

Userland/Libraries/LibWebSocket/Impl/WebSocketImpl.cpp

@@ -63,8 +63,8 @@ ErrorOr<ByteBuffer> WebSocketImpl::read(int max_size)
 ErrorOr<String> WebSocketImpl::read_line(size_t size)
 {
     auto buffer = TRY(ByteBuffer::create_uninitialized(size));
-    auto nread = TRY(m_socket->read_line(buffer));
+    auto line = TRY(m_socket->read_line(buffer));
-    return String::copy(buffer.span().slice(0, nread));
+    return line.to_string();
 }
 
 }