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