1 //===-- CompletionRequest.cpp -----------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Utility/CompletionRequest.h"
10 
11 using namespace lldb;
12 using namespace lldb_private;
13 
14 CompletionRequest::CompletionRequest(llvm::StringRef command_line,
15                                      unsigned raw_cursor_pos,
16                                      CompletionResult &result)
17     : m_command(command_line), m_raw_cursor_pos(raw_cursor_pos),
18       m_result(result) {
19   assert(raw_cursor_pos <= command_line.size() && "Out of bounds cursor?");
20 
21   // We parse the argument up to the cursor, so the last argument in
22   // parsed_line is the one containing the cursor, and the cursor is after the
23   // last character.
24   m_parsed_line = Args(command_line);
25   m_partial_parsed_line = Args(command_line.substr(0, raw_cursor_pos));
26 
27   m_cursor_index = m_partial_parsed_line.GetArgumentCount() - 1;
28 
29   if (m_cursor_index == -1)
30     m_cursor_char_position = 0;
31   else
32     m_cursor_char_position =
33         strlen(m_partial_parsed_line.GetArgumentAtIndex(m_cursor_index));
34 
35   const char *cursor = command_line.data() + raw_cursor_pos;
36   if (raw_cursor_pos > 0 && cursor[-1] == ' ') {
37     // We are just after a space.  If we are in an argument, then we will
38     // continue parsing, but if we are between arguments, then we have to
39     // complete whatever the next element would be. We can distinguish the two
40     // cases because if we are in an argument (e.g. because the space is
41     // protected by a quote) then the space will also be in the parsed
42     // argument...
43 
44     const char *current_elem =
45         m_partial_parsed_line.GetArgumentAtIndex(m_cursor_index);
46     if (m_cursor_char_position == 0 ||
47         current_elem[m_cursor_char_position - 1] != ' ') {
48       m_parsed_line.InsertArgumentAtIndex(m_cursor_index + 1, llvm::StringRef(),
49                                           '\0');
50       m_cursor_index++;
51       m_cursor_char_position = 0;
52     }
53   }
54 }
55 
56 std::string CompletionResult::Completion::GetUniqueKey() const {
57 
58   // We build a unique key for this pair of completion:description. We
59   // prefix the key with the length of the completion string. This prevents
60   // that we could get any collisions from completions pairs such as these:
61   // "foo:", "bar" would be "foo:bar", but will now be: "4foo:bar"
62   // "foo", ":bar" would be "foo:bar", but will now be: "3foo:bar"
63 
64   std::string result;
65   result.append(std::to_string(m_completion.size()));
66   result.append(m_completion);
67   result.append(m_descripton);
68   return result;
69 }
70 
71 void CompletionResult::AddResult(llvm::StringRef completion,
72                                  llvm::StringRef description) {
73   Completion r(completion, description);
74 
75   // Add the completion if we haven't seen the same value before.
76   if (m_added_values.insert(r.GetUniqueKey()).second)
77     m_results.push_back(r);
78 }
79 
80 void CompletionResult::GetMatches(StringList &matches) const {
81   matches.Clear();
82   for (const Completion &completion : m_results)
83     matches.AppendString(completion.m_completion);
84 }
85 
86 void CompletionResult::GetDescriptions(StringList &descriptions) const {
87   descriptions.Clear();
88   for (const Completion &completion : m_results)
89     descriptions.AppendString(completion.m_descripton);
90 }
91