Files
clang-p2996/lldb/source/Commands/CommandObjectMultiword.cpp
Raphael Isemann 1a6d7ab55d Narrow the CompletionRequest API to being append-only.
Summary:
We currently allow any completion handler to read and manipulate the list of matches we
calculated so far. This leads to a few problems:

Firstly, a completion handler's logic can now depend on previously calculated results
by another handlers. No completion handler should have such an implicit dependency,
but the current API makes it likely that this could happen (or already happens). Especially
the fact that some completion handler deleted all previously calculated results can mess
things up right now.

Secondly, all completion handlers have knowledge about our internal data structures with
this API. This makes refactoring this internal data structure much harder than it should be.
Especially planned changes like the support of descriptions for completions are currently
giant patches because we have to refactor every single completion handler.

This patch narrows the contract the CompletionRequest has with the different handlers to:

1. A handler can suggest a completion.
2. A handler can ask how many suggestions we already have.

Point 2 obviously means we still have a  dependency left between the different handlers, but
getting rid of this is too large to just append it to this patch.

Otherwise this patch just completely hides the internal StringList to the different handlers.

The CompletionRequest API now also ensures that the list of completions is unique and we
don't suggest the same value multiple times to the user. This property has been so far only
been ensured by the `Option` handler, but is now applied globally. This is part of this patch
as the OptionHandler is no longer able to implement this functionality itself.

Reviewers: jingham, davide, labath

Reviewed By: davide

Subscribers: lldb-commits

Differential Revision: https://reviews.llvm.org/D49322

llvm-svn: 338151
2018-07-27 18:42:46 +00:00

401 lines
14 KiB
C++

//===-- CommandObjectMultiword.cpp ------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// C Includes
// C++ Includes
// Other libraries and framework includes
// Project includes
#include "lldb/Interpreter/CommandObjectMultiword.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/CommandReturnObject.h"
#include "lldb/Interpreter/Options.h"
using namespace lldb;
using namespace lldb_private;
//-------------------------------------------------------------------------
// CommandObjectMultiword
//-------------------------------------------------------------------------
CommandObjectMultiword::CommandObjectMultiword(CommandInterpreter &interpreter,
const char *name,
const char *help,
const char *syntax,
uint32_t flags)
: CommandObject(interpreter, name, help, syntax, flags),
m_can_be_removed(false) {}
CommandObjectMultiword::~CommandObjectMultiword() = default;
CommandObjectSP CommandObjectMultiword::GetSubcommandSP(llvm::StringRef sub_cmd,
StringList *matches) {
CommandObjectSP return_cmd_sp;
CommandObject::CommandMap::iterator pos;
if (!m_subcommand_dict.empty()) {
pos = m_subcommand_dict.find(sub_cmd);
if (pos != m_subcommand_dict.end()) {
// An exact match; append the sub_cmd to the 'matches' string list.
if (matches)
matches->AppendString(sub_cmd);
return_cmd_sp = pos->second;
} else {
StringList local_matches;
if (matches == nullptr)
matches = &local_matches;
int num_matches =
AddNamesMatchingPartialString(m_subcommand_dict, sub_cmd, *matches);
if (num_matches == 1) {
// Cleaner, but slightly less efficient would be to call back into this
// function, since I now know I have an exact match...
sub_cmd = matches->GetStringAtIndex(0);
pos = m_subcommand_dict.find(sub_cmd);
if (pos != m_subcommand_dict.end())
return_cmd_sp = pos->second;
}
}
}
return return_cmd_sp;
}
CommandObject *
CommandObjectMultiword::GetSubcommandObject(llvm::StringRef sub_cmd,
StringList *matches) {
return GetSubcommandSP(sub_cmd, matches).get();
}
bool CommandObjectMultiword::LoadSubCommand(llvm::StringRef name,
const CommandObjectSP &cmd_obj) {
if (cmd_obj)
assert((&GetCommandInterpreter() == &cmd_obj->GetCommandInterpreter()) &&
"tried to add a CommandObject from a different interpreter");
CommandMap::iterator pos;
bool success = true;
pos = m_subcommand_dict.find(name);
if (pos == m_subcommand_dict.end()) {
m_subcommand_dict[name] = cmd_obj;
} else
success = false;
return success;
}
bool CommandObjectMultiword::Execute(const char *args_string,
CommandReturnObject &result) {
Args args(args_string);
const size_t argc = args.GetArgumentCount();
if (argc == 0) {
this->CommandObject::GenerateHelpText(result);
return result.Succeeded();
}
auto sub_command = args[0].ref;
if (sub_command.empty())
return result.Succeeded();
if (sub_command.equals_lower("help")) {
this->CommandObject::GenerateHelpText(result);
return result.Succeeded();
}
if (m_subcommand_dict.empty()) {
result.AppendErrorWithFormat("'%s' does not have any subcommands.\n",
GetCommandName().str().c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
StringList matches;
CommandObject *sub_cmd_obj = GetSubcommandObject(sub_command, &matches);
if (sub_cmd_obj != nullptr) {
// Now call CommandObject::Execute to process options in `rest_of_line`.
// From there the command-specific version of Execute will be called, with
// the processed arguments.
args.Shift();
sub_cmd_obj->Execute(args_string, result);
return result.Succeeded();
}
std::string error_msg;
const size_t num_subcmd_matches = matches.GetSize();
if (num_subcmd_matches > 0)
error_msg.assign("ambiguous command ");
else
error_msg.assign("invalid command ");
error_msg.append("'");
error_msg.append(GetCommandName());
error_msg.append(" ");
error_msg.append(sub_command);
error_msg.append("'.");
if (num_subcmd_matches > 0) {
error_msg.append(" Possible completions:");
for (size_t i = 0; i < matches.GetSize(); i++) {
error_msg.append("\n\t");
error_msg.append(matches.GetStringAtIndex(i));
}
}
error_msg.append("\n");
result.AppendRawError(error_msg.c_str());
result.SetStatus(eReturnStatusFailed);
return false;
}
void CommandObjectMultiword::GenerateHelpText(Stream &output_stream) {
// First time through here, generate the help text for the object and push it
// to the return result object as well
CommandObject::GenerateHelpText(output_stream);
output_stream.PutCString("\nThe following subcommands are supported:\n\n");
CommandMap::iterator pos;
uint32_t max_len = FindLongestCommandWord(m_subcommand_dict);
if (max_len)
max_len += 4; // Indent the output by 4 spaces.
for (pos = m_subcommand_dict.begin(); pos != m_subcommand_dict.end(); ++pos) {
std::string indented_command(" ");
indented_command.append(pos->first);
if (pos->second->WantsRawCommandString()) {
std::string help_text(pos->second->GetHelp());
help_text.append(" Expects 'raw' input (see 'help raw-input'.)");
m_interpreter.OutputFormattedHelpText(output_stream,
indented_command.c_str(), "--",
help_text.c_str(), max_len);
} else
m_interpreter.OutputFormattedHelpText(output_stream,
indented_command.c_str(), "--",
pos->second->GetHelp(), max_len);
}
output_stream.PutCString("\nFor more help on any particular subcommand, type "
"'help <command> <subcommand>'.\n");
}
int CommandObjectMultiword::HandleCompletion(CompletionRequest &request) {
// Any of the command matches will provide a complete word, otherwise the
// individual completers will override this.
request.SetWordComplete(true);
auto arg0 = request.GetParsedLine()[0].ref;
if (request.GetCursorIndex() == 0) {
StringList new_matches;
AddNamesMatchingPartialString(m_subcommand_dict, arg0, new_matches);
request.AddCompletions(new_matches);
if (new_matches.GetSize() == 1 &&
new_matches.GetStringAtIndex(0) != nullptr &&
(arg0 == new_matches.GetStringAtIndex(0))) {
StringList temp_matches;
CommandObject *cmd_obj = GetSubcommandObject(arg0, &temp_matches);
if (cmd_obj != nullptr) {
if (request.GetParsedLine().GetArgumentCount() == 1) {
request.SetWordComplete(true);
} else {
request.GetParsedLine().Shift();
request.SetCursorCharPosition(0);
request.GetParsedLine().AppendArgument(llvm::StringRef());
return cmd_obj->HandleCompletion(request);
}
}
}
return new_matches.GetSize();
} else {
StringList new_matches;
CommandObject *sub_command_object = GetSubcommandObject(arg0, &new_matches);
if (sub_command_object == nullptr) {
request.AddCompletions(new_matches);
return request.GetNumberOfMatches();
} else {
// Remove the one match that we got from calling GetSubcommandObject.
new_matches.DeleteStringAtIndex(0);
request.AddCompletions(new_matches);
request.GetParsedLine().Shift();
request.SetCursorIndex(request.GetCursorIndex() - 1);
return sub_command_object->HandleCompletion(request);
}
}
}
const char *CommandObjectMultiword::GetRepeatCommand(Args &current_command_args,
uint32_t index) {
index++;
if (current_command_args.GetArgumentCount() <= index)
return nullptr;
CommandObject *sub_command_object =
GetSubcommandObject(current_command_args[index].ref);
if (sub_command_object == nullptr)
return nullptr;
return sub_command_object->GetRepeatCommand(current_command_args, index);
}
void CommandObjectMultiword::AproposAllSubCommands(llvm::StringRef prefix,
llvm::StringRef search_word,
StringList &commands_found,
StringList &commands_help) {
CommandObject::CommandMap::const_iterator pos;
for (pos = m_subcommand_dict.begin(); pos != m_subcommand_dict.end(); ++pos) {
const char *command_name = pos->first.c_str();
CommandObject *sub_cmd_obj = pos->second.get();
StreamString complete_command_name;
complete_command_name << prefix << " " << command_name;
if (sub_cmd_obj->HelpTextContainsWord(search_word)) {
commands_found.AppendString(complete_command_name.GetString());
commands_help.AppendString(sub_cmd_obj->GetHelp());
}
if (sub_cmd_obj->IsMultiwordObject())
sub_cmd_obj->AproposAllSubCommands(complete_command_name.GetString(),
search_word, commands_found,
commands_help);
}
}
CommandObjectProxy::CommandObjectProxy(CommandInterpreter &interpreter,
const char *name, const char *help,
const char *syntax, uint32_t flags)
: CommandObject(interpreter, name, help, syntax, flags) {}
CommandObjectProxy::~CommandObjectProxy() = default;
llvm::StringRef CommandObjectProxy::GetHelpLong() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetHelpLong();
return llvm::StringRef();
}
bool CommandObjectProxy::IsRemovable() const {
const CommandObject *proxy_command =
const_cast<CommandObjectProxy *>(this)->GetProxyCommandObject();
if (proxy_command)
return proxy_command->IsRemovable();
return false;
}
bool CommandObjectProxy::IsMultiwordObject() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->IsMultiwordObject();
return false;
}
CommandObjectMultiword *CommandObjectProxy::GetAsMultiwordCommand() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetAsMultiwordCommand();
return nullptr;
}
void CommandObjectProxy::GenerateHelpText(Stream &result) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GenerateHelpText(result);
}
lldb::CommandObjectSP
CommandObjectProxy::GetSubcommandSP(llvm::StringRef sub_cmd,
StringList *matches) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetSubcommandSP(sub_cmd, matches);
return lldb::CommandObjectSP();
}
CommandObject *CommandObjectProxy::GetSubcommandObject(llvm::StringRef sub_cmd,
StringList *matches) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetSubcommandObject(sub_cmd, matches);
return nullptr;
}
void CommandObjectProxy::AproposAllSubCommands(llvm::StringRef prefix,
llvm::StringRef search_word,
StringList &commands_found,
StringList &commands_help) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->AproposAllSubCommands(prefix, search_word,
commands_found, commands_help);
}
bool CommandObjectProxy::LoadSubCommand(
llvm::StringRef cmd_name, const lldb::CommandObjectSP &command_sp) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->LoadSubCommand(cmd_name, command_sp);
return false;
}
bool CommandObjectProxy::WantsRawCommandString() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->WantsRawCommandString();
return false;
}
bool CommandObjectProxy::WantsCompletion() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->WantsCompletion();
return false;
}
Options *CommandObjectProxy::GetOptions() {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetOptions();
return nullptr;
}
int CommandObjectProxy::HandleCompletion(CompletionRequest &request) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->HandleCompletion(request);
return 0;
}
int CommandObjectProxy::HandleArgumentCompletion(
CompletionRequest &request, OptionElementVector &opt_element_vector) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->HandleArgumentCompletion(request, opt_element_vector);
return 0;
}
const char *CommandObjectProxy::GetRepeatCommand(Args &current_command_args,
uint32_t index) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->GetRepeatCommand(current_command_args, index);
return nullptr;
}
bool CommandObjectProxy::Execute(const char *args_string,
CommandReturnObject &result) {
CommandObject *proxy_command = GetProxyCommandObject();
if (proxy_command)
return proxy_command->Execute(args_string, result);
result.AppendError("command is not implemented");
result.SetStatus(eReturnStatusFailed);
return false;
}