1//===--- CommentCommandTraits.cpp - Comment command properties --*- 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 "clang/AST/CommentCommandTraits.h"
10#include "llvm/ADT/STLExtras.h"
11#include <cassert>
12
13namespace clang {
14namespace comments {
15
16#include "clang/AST/CommentCommandInfo.inc"
17
18CommandTraits::CommandTraits(llvm::BumpPtrAllocator &Allocator,
19 const CommentOptions &CommentOptions)
20 : NextID(std::size(Commands)), Allocator(Allocator) {
21 registerCommentOptions(CommentOptions);
22}
23
24void CommandTraits::registerCommentOptions(
25 const CommentOptions &CommentOptions) {
26 for (CommentOptions::BlockCommandNamesTy::const_iterator
27 I = CommentOptions.BlockCommandNames.begin(),
28 E = CommentOptions.BlockCommandNames.end();
29 I != E; I++) {
30 registerBlockCommand(CommandName: *I);
31 }
32}
33
34const CommandInfo *CommandTraits::getCommandInfoOrNULL(StringRef Name) const {
35 if (const CommandInfo *Info = getBuiltinCommandInfo(Name))
36 return Info;
37 return getRegisteredCommandInfo(Name);
38}
39
40const CommandInfo *CommandTraits::getCommandInfo(unsigned CommandID) const {
41 if (const CommandInfo *Info = getBuiltinCommandInfo(CommandID))
42 return Info;
43 return getRegisteredCommandInfo(CommandID);
44}
45
46const CommandInfo *
47CommandTraits::getTypoCorrectCommandInfo(StringRef Typo) const {
48 // Single-character command impostures, such as \t or \n, should not go
49 // through the fixit logic.
50 if (Typo.size() <= 1)
51 return nullptr;
52
53 // The maximum edit distance we're prepared to accept.
54 const unsigned MaxEditDistance = 1;
55
56 unsigned BestEditDistance = MaxEditDistance;
57 SmallVector<const CommandInfo *, 2> BestCommand;
58
59 auto ConsiderCorrection = [&](const CommandInfo *Command) {
60 StringRef Name = Command->Name;
61
62 unsigned MinPossibleEditDistance = abs(x: (int)Name.size() - (int)Typo.size());
63 if (MinPossibleEditDistance <= BestEditDistance) {
64 unsigned EditDistance = Typo.edit_distance(Other: Name, AllowReplacements: true, MaxEditDistance: BestEditDistance);
65 if (EditDistance < BestEditDistance) {
66 BestEditDistance = EditDistance;
67 BestCommand.clear();
68 }
69 if (EditDistance == BestEditDistance)
70 BestCommand.push_back(Elt: Command);
71 }
72 };
73
74 for (const auto &Command : Commands)
75 ConsiderCorrection(&Command);
76
77 for (const auto *Command : RegisteredCommands)
78 if (!Command->IsUnknownCommand)
79 ConsiderCorrection(Command);
80
81 return BestCommand.size() == 1 ? BestCommand[0] : nullptr;
82}
83
84CommandInfo *CommandTraits::createCommandInfoWithName(StringRef CommandName) {
85 char *Name = Allocator.Allocate<char>(Num: CommandName.size() + 1);
86 memcpy(dest: Name, src: CommandName.data(), n: CommandName.size());
87 Name[CommandName.size()] = '\0';
88
89 // Value-initialize (=zero-initialize in this case) a new CommandInfo.
90 CommandInfo *Info = new (Allocator) CommandInfo();
91 Info->Name = Name;
92 // We only have a limited number of bits to encode command IDs in the
93 // CommandInfo structure, so the ID numbers can potentially wrap around.
94 assert((NextID < (1 << CommandInfo::NumCommandIDBits))
95 && "Too many commands. We have limited bits for the command ID.");
96 Info->ID = NextID++;
97
98 RegisteredCommands.push_back(Elt: Info);
99
100 return Info;
101}
102
103const CommandInfo *CommandTraits::registerUnknownCommand(
104 StringRef CommandName) {
105 CommandInfo *Info = createCommandInfoWithName(CommandName);
106 Info->IsUnknownCommand = true;
107 return Info;
108}
109
110const CommandInfo *CommandTraits::registerBlockCommand(StringRef CommandName) {
111 CommandInfo *Info = createCommandInfoWithName(CommandName);
112 Info->IsBlockCommand = true;
113 return Info;
114}
115
116const CommandInfo *CommandTraits::getBuiltinCommandInfo(
117 unsigned CommandID) {
118 if (CommandID < std::size(Commands))
119 return &Commands[CommandID];
120 return nullptr;
121}
122
123const CommandInfo *CommandTraits::getRegisteredCommandInfo(
124 StringRef Name) const {
125 for (unsigned i = 0, e = RegisteredCommands.size(); i != e; ++i) {
126 if (RegisteredCommands[i]->Name == Name)
127 return RegisteredCommands[i];
128 }
129 return nullptr;
130}
131
132const CommandInfo *CommandTraits::getRegisteredCommandInfo(
133 unsigned CommandID) const {
134 return RegisteredCommands[CommandID - std::size(Commands)];
135}
136
137} // end namespace comments
138} // end namespace clang
139
140