HackStudio+CppLanguageServer: Remove lexer-based autocomplete engine

The parser-based autocomplete engine is at a point where it's stable
enough that I don't think there's a need for the lexer-based
alternative anymore.

Userland/DevTools/HackStudio/HackStudioWidget.cpp

@@ -898,8 +898,6 @@ void HackStudioWidget::create_project_menubar(GUI::Menubar& menubar)
     auto& project_menu = menubar.add_menu("&Project");
     project_menu.add_action(*m_new_file_action);
     project_menu.add_action(*m_new_directory_action);
-    project_menu.add_separator();
-    project_menu.add_action(*create_set_autocomplete_mode_action());
 }
 
 void HackStudioWidget::create_edit_menubar(GUI::Menubar& menubar)
@@ -1000,15 +998,6 @@ NonnullRefPtr<GUI::Action> HackStudioWidget::create_stop_action()
     return action;
 }
 
-NonnullRefPtr<GUI::Action> HackStudioWidget::create_set_autocomplete_mode_action()
-{
-    auto action = GUI::Action::create_checkable("AutoComplete C++ with &Parser", [this](auto& action) {
-        get_language_client<LanguageClients::Cpp::ServerConnection>(project().root_path())->set_autocomplete_mode(action.is_checked() ? "Parser" : "Lexer");
-    });
-    action->set_checked(true);
-    return action;
-}
-
 void HackStudioWidget::initialize_menubar(GUI::Menubar& menubar)
 {
     create_file_menubar(menubar);

Userland/DevTools/HackStudio/HackStudioWidget.h

@@ -88,7 +88,6 @@ private:
     NonnullRefPtr<GUI::Action> create_build_action();
     NonnullRefPtr<GUI::Action> create_run_action();
     NonnullRefPtr<GUI::Action> create_stop_action();
-    NonnullRefPtr<GUI::Action> create_set_autocomplete_mode_action();
 
     void add_new_editor(GUI::Widget& parent);
     RefPtr<EditorWrapper> get_editor_of_file(const String& filename);

Userland/DevTools/HackStudio/LanguageClient.cpp

@@ -84,13 +84,6 @@ void LanguageClient::provide_autocomplete_suggestions(const Vector<GUI::Autocomp
     // Otherwise, drop it on the floor :shrug:
 }
 
-void LanguageClient::set_autocomplete_mode(const String& mode)
-{
-    if (!m_connection_wrapper.connection())
-        return;
-    m_connection_wrapper.connection()->async_set_auto_complete_mode(mode);
-}
-
 void LanguageClient::set_active_client()
 {
     if (!m_connection_wrapper.connection())

Userland/DevTools/HackStudio/LanguageClient.h

@@ -128,7 +128,6 @@ public:
     virtual void insert_text(const String& path, const String& text, size_t line, size_t column);
     virtual void remove_text(const String& path, size_t from_line, size_t from_column, size_t to_line, size_t to_column);
     virtual void request_autocomplete(const String& path, size_t cursor_line, size_t cursor_column);
-    virtual void set_autocomplete_mode(const String& mode);
     virtual void search_declaration(const String& path, size_t line, size_t column);
 
     void provide_autocomplete_suggestions(const Vector<GUI::AutocompleteProvider::Entry>&) const;

Userland/DevTools/HackStudio/LanguageServers/ClientConnection.h

@@ -34,7 +34,6 @@ protected:
     virtual void set_file_content(String const&, String const&) override;
     virtual void auto_complete_suggestions(GUI::AutocompleteProvider::ProjectLocation const&) override;
     virtual void find_declaration(GUI::AutocompleteProvider::ProjectLocation const&) override;
-    virtual void set_auto_complete_mode(String const&) override = 0;
 
     FileDB m_filedb;
     OwnPtr<AutoCompleteEngine> m_autocomplete_engine;

Userland/DevTools/HackStudio/LanguageServers/Cpp/CMakeLists.txt

@@ -1,5 +1,4 @@
 set(SOURCES
-    LexerAutoComplete.cpp
     ParserAutoComplete.cpp
     Tests.cpp
     main.cpp

Userland/DevTools/HackStudio/LanguageServers/Cpp/ClientConnection.h

@@ -6,7 +6,6 @@
 
 #pragma once
 
-#include "LexerAutoComplete.h"
 #include "ParserAutoComplete.h"
 #include <DevTools/HackStudio/LanguageServers/ClientConnection.h>
 
@@ -26,15 +25,5 @@ public:
     }
 
     virtual ~ClientConnection() override = default;
-
-private:
-    virtual void set_auto_complete_mode(String const& mode) override
-    {
-        dbgln_if(CPP_LANGUAGE_SERVER_DEBUG, "SetAutoCompleteMode: {}", mode);
-        if (mode == "Parser")
-            m_autocomplete_engine = make<ParserAutoComplete>(m_filedb);
-        else
-            m_autocomplete_engine = make<LexerAutoComplete>(m_filedb);
-    }
 };
 }

Userland/DevTools/HackStudio/LanguageServers/Cpp/LexerAutoComplete.cpp

@@ -1,87 +0,0 @@
-/*
- * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#include "LexerAutoComplete.h"
-#include <AK/Debug.h>
-#include <AK/HashTable.h>
-#include <LibCpp/Lexer.h>
-
-namespace LanguageServers::Cpp {
-
-LexerAutoComplete::LexerAutoComplete(const FileDB& filedb)
-    : AutoCompleteEngine(filedb)
-{
-}
-
-Vector<GUI::AutocompleteProvider::Entry> LexerAutoComplete::get_suggestions(const String& file, const GUI::TextPosition& autocomplete_position)
-{
-    auto document = filedb().get(file);
-    if (!document) {
-        dbgln("didn't find document for {}", file);
-        return {};
-    }
-    auto code = document->text();
-    auto lines = code.split('\n', true);
-    Cpp::Lexer lexer(code);
-    auto tokens = lexer.lex();
-
-    auto index_of_target_token = token_in_position(tokens, autocomplete_position);
-    if (!index_of_target_token.has_value())
-        return {};
-
-    auto suggestions = identifier_prefixes(lines, tokens, index_of_target_token.value());
-
-    if constexpr (AUTOCOMPLETE_DEBUG) {
-        for (auto& suggestion : suggestions) {
-            dbgln("suggestion: {}", suggestion.completion);
-        }
-    }
-
-    return suggestions;
-}
-
-StringView LexerAutoComplete::text_of_token(const Vector<String>& lines, const Cpp::Token& token)
-{
-    VERIFY(token.start().line == token.end().line);
-    VERIFY(token.start().column <= token.end().column);
-    return lines[token.start().line].substring_view(token.start().column, token.end().column - token.start().column + 1);
-}
-
-Optional<size_t> LexerAutoComplete::token_in_position(const Vector<Cpp::Token>& tokens, const GUI::TextPosition& position)
-{
-    for (size_t token_index = 0; token_index < tokens.size(); ++token_index) {
-        auto& token = tokens[token_index];
-        if (token.start().line != token.end().line)
-            continue;
-        if (token.start().line != position.line())
-            continue;
-        if (token.start().column + 1 > position.column() || token.end().column + 1 < position.column())
-            continue;
-        return token_index;
-    }
-    return {};
-}
-
-Vector<GUI::AutocompleteProvider::Entry> LexerAutoComplete::identifier_prefixes(const Vector<String>& lines, const Vector<Cpp::Token>& tokens, size_t target_token_index)
-{
-    auto partial_input = text_of_token(lines, tokens[target_token_index]);
-    Vector<GUI::AutocompleteProvider::Entry> suggestions;
-
-    HashTable<String> suggestions_lookup; // To avoid duplicate results
-
-    for (size_t i = 0; i < target_token_index; ++i) {
-        auto& token = tokens[i];
-        if (token.type() != Cpp::Token::Type::Identifier)
-            continue;
-        auto text = text_of_token(lines, token);
-        if (text.starts_with(partial_input) && suggestions_lookup.set(text) == AK::HashSetResult::InsertedNewEntry) {
-            suggestions.append({ text, partial_input.length(), GUI::AutocompleteProvider::CompletionKind::Identifier });
-        }
-    }
-    return suggestions;
-}
-
-}

Userland/DevTools/HackStudio/LanguageServers/Cpp/LexerAutoComplete.h

@@ -1,32 +0,0 @@
-/*
- * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#pragma once
-
-#include <AK/String.h>
-#include <AK/Vector.h>
-#include <DevTools/HackStudio/AutoCompleteResponse.h>
-#include <DevTools/HackStudio/LanguageServers/AutoCompleteEngine.h>
-#include <LibCpp/Lexer.h>
-#include <LibGUI/TextPosition.h>
-
-namespace LanguageServers::Cpp {
-
-using namespace ::Cpp;
-
-class LexerAutoComplete : public AutoCompleteEngine {
-public:
-    LexerAutoComplete(const FileDB& filedb);
-
-    virtual Vector<GUI::AutocompleteProvider::Entry> get_suggestions(const String& file, const GUI::TextPosition& autocomplete_position) override;
-
-private:
-    Optional<size_t> token_in_position(const Vector<Cpp::Token>&, const GUI::TextPosition&);
-    StringView text_of_token(const Vector<String>& lines, const Cpp::Token&);
-    Vector<GUI::AutocompleteProvider::Entry> identifier_prefixes(const Vector<String>& lines, const Vector<Cpp::Token>&, size_t target_token_index);
-};
-
-}

Userland/DevTools/HackStudio/LanguageServers/LanguageServer.ipc

@@ -8,6 +8,5 @@ endpoint LanguageServer
     set_file_content(String filename, String content) =|
 
     auto_complete_suggestions(GUI::AutocompleteProvider::ProjectLocation location) =|
-    set_auto_complete_mode(String mode) =|
     find_declaration(GUI::AutocompleteProvider::ProjectLocation location) =|
 }

Userland/DevTools/HackStudio/LanguageServers/Shell/ClientConnection.h

@@ -23,8 +23,5 @@ class ClientConnection final : public LanguageServers::ClientConnection {
         };
     }
     virtual ~ClientConnection() override = default;
-
-private:
-    virtual void set_auto_complete_mode(String const&) override { }
 };
 }