1//===--- IdentifierLengthCheck.cpp - clang-tidy
2//-----------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#include "IdentifierLengthCheck.h"
11#include "clang/ASTMatchers/ASTMatchFinder.h"
12
13using namespace clang::ast_matchers;
14
15namespace clang::tidy::readability {
16
17const unsigned DefaultMinimumVariableNameLength = 3;
18const unsigned DefaultMinimumLoopCounterNameLength = 2;
19const unsigned DefaultMinimumExceptionNameLength = 2;
20const unsigned DefaultMinimumParameterNameLength = 3;
21const char DefaultIgnoredLoopCounterNames[] = "^[ijk_]$";
22const char DefaultIgnoredVariableNames[] = "";
23const char DefaultIgnoredExceptionVariableNames[] = "^[e]$";
24const char DefaultIgnoredParameterNames[] = "^[n]$";
25
26const char ErrorMessage[] =
27 "%select{variable|exception variable|loop variable|"
28 "parameter}0 name %1 is too short, expected at least %2 characters";
29
30IdentifierLengthCheck::IdentifierLengthCheck(StringRef Name,
31 ClangTidyContext *Context)
32 : ClangTidyCheck(Name, Context),
33 MinimumVariableNameLength(Options.get(LocalName: "MinimumVariableNameLength",
34 Default: DefaultMinimumVariableNameLength)),
35 MinimumLoopCounterNameLength(Options.get(
36 LocalName: "MinimumLoopCounterNameLength", Default: DefaultMinimumLoopCounterNameLength)),
37 MinimumExceptionNameLength(Options.get(
38 LocalName: "MinimumExceptionNameLength", Default: DefaultMinimumExceptionNameLength)),
39 MinimumParameterNameLength(Options.get(
40 LocalName: "MinimumParameterNameLength", Default: DefaultMinimumParameterNameLength)),
41 IgnoredVariableNamesInput(
42 Options.get(LocalName: "IgnoredVariableNames", Default: DefaultIgnoredVariableNames)),
43 IgnoredVariableNames(IgnoredVariableNamesInput),
44 IgnoredLoopCounterNamesInput(Options.get(LocalName: "IgnoredLoopCounterNames",
45 Default: DefaultIgnoredLoopCounterNames)),
46 IgnoredLoopCounterNames(IgnoredLoopCounterNamesInput),
47 IgnoredExceptionVariableNamesInput(
48 Options.get(LocalName: "IgnoredExceptionVariableNames",
49 Default: DefaultIgnoredExceptionVariableNames)),
50 IgnoredExceptionVariableNames(IgnoredExceptionVariableNamesInput),
51 IgnoredParameterNamesInput(
52 Options.get(LocalName: "IgnoredParameterNames", Default: DefaultIgnoredParameterNames)),
53 IgnoredParameterNames(IgnoredParameterNamesInput) {}
54
55void IdentifierLengthCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
56 Options.store(Options&: Opts, LocalName: "MinimumVariableNameLength", Value: MinimumVariableNameLength);
57 Options.store(Options&: Opts, LocalName: "MinimumLoopCounterNameLength",
58 Value: MinimumLoopCounterNameLength);
59 Options.store(Options&: Opts, LocalName: "MinimumExceptionNameLength", Value: MinimumExceptionNameLength);
60 Options.store(Options&: Opts, LocalName: "MinimumParameterNameLength", Value: MinimumParameterNameLength);
61 Options.store(Options&: Opts, LocalName: "IgnoredLoopCounterNames", Value: IgnoredLoopCounterNamesInput);
62 Options.store(Options&: Opts, LocalName: "IgnoredVariableNames", Value: IgnoredVariableNamesInput);
63 Options.store(Options&: Opts, LocalName: "IgnoredExceptionVariableNames",
64 Value: IgnoredExceptionVariableNamesInput);
65 Options.store(Options&: Opts, LocalName: "IgnoredParameterNames", Value: IgnoredParameterNamesInput);
66}
67
68void IdentifierLengthCheck::registerMatchers(MatchFinder *Finder) {
69 if (MinimumLoopCounterNameLength > 1)
70 Finder->addMatcher(
71 NodeMatch: forStmt(hasLoopInit(InnerMatcher: declStmt(forEach(varDecl().bind(ID: "loopVar"))))),
72 Action: this);
73
74 if (MinimumExceptionNameLength > 1)
75 Finder->addMatcher(NodeMatch: varDecl(hasParent(cxxCatchStmt())).bind(ID: "exceptionVar"),
76 Action: this);
77
78 if (MinimumParameterNameLength > 1)
79 Finder->addMatcher(NodeMatch: parmVarDecl().bind(ID: "paramVar"), Action: this);
80
81 if (MinimumVariableNameLength > 1)
82 Finder->addMatcher(
83 NodeMatch: varDecl(unless(anyOf(hasParent(declStmt(hasParent(forStmt()))),
84 hasParent(cxxCatchStmt()), parmVarDecl())))
85 .bind(ID: "standaloneVar"),
86 Action: this);
87}
88
89void IdentifierLengthCheck::check(const MatchFinder::MatchResult &Result) {
90 const auto *StandaloneVar = Result.Nodes.getNodeAs<VarDecl>(ID: "standaloneVar");
91 if (StandaloneVar) {
92 if (!StandaloneVar->getIdentifier())
93 return;
94
95 StringRef VarName = StandaloneVar->getName();
96
97 if (VarName.size() >= MinimumVariableNameLength ||
98 IgnoredVariableNames.match(String: VarName))
99 return;
100
101 diag(StandaloneVar->getLocation(), ErrorMessage)
102 << 0 << StandaloneVar << MinimumVariableNameLength;
103 }
104
105 auto *ExceptionVarName = Result.Nodes.getNodeAs<VarDecl>(ID: "exceptionVar");
106 if (ExceptionVarName) {
107 if (!ExceptionVarName->getIdentifier())
108 return;
109
110 StringRef VarName = ExceptionVarName->getName();
111 if (VarName.size() >= MinimumExceptionNameLength ||
112 IgnoredExceptionVariableNames.match(String: VarName))
113 return;
114
115 diag(ExceptionVarName->getLocation(), ErrorMessage)
116 << 1 << ExceptionVarName << MinimumExceptionNameLength;
117 }
118
119 const auto *LoopVar = Result.Nodes.getNodeAs<VarDecl>(ID: "loopVar");
120 if (LoopVar) {
121 if (!LoopVar->getIdentifier())
122 return;
123
124 StringRef VarName = LoopVar->getName();
125
126 if (VarName.size() >= MinimumLoopCounterNameLength ||
127 IgnoredLoopCounterNames.match(String: VarName))
128 return;
129
130 diag(LoopVar->getLocation(), ErrorMessage)
131 << 2 << LoopVar << MinimumLoopCounterNameLength;
132 }
133
134 const auto *ParamVar = Result.Nodes.getNodeAs<VarDecl>(ID: "paramVar");
135 if (ParamVar) {
136 if (!ParamVar->getIdentifier())
137 return;
138
139 StringRef VarName = ParamVar->getName();
140
141 if (VarName.size() >= MinimumParameterNameLength ||
142 IgnoredParameterNames.match(String: VarName))
143 return;
144
145 diag(ParamVar->getLocation(), ErrorMessage)
146 << 3 << ParamVar << MinimumParameterNameLength;
147 }
148}
149
150} // namespace clang::tidy::readability
151

source code of clang-tools-extra/clang-tidy/readability/IdentifierLengthCheck.cpp