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