1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
| //===--- MisleadingIndentationCheck.cpp - clang-tidy-----------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "MisleadingIndentationCheck.h"
#include "clang/AST/ASTContext.h"
#include "clang/ASTMatchers/ASTMatchFinder.h"
using namespace clang::ast_matchers;
namespace clang {
namespace tidy {
namespace readability {
static const IfStmt *getPrecedingIf(const SourceManager &SM,
ASTContext *Context, const IfStmt *If) {
auto parents = Context->getParents(*If);
if (parents.size() != 1)
return nullptr;
if (const auto *PrecedingIf = parents[0].get<IfStmt>()) {
SourceLocation PreviousElseLoc = PrecedingIf->getElseLoc();
if (SM.getExpansionLineNumber(PreviousElseLoc) ==
SM.getExpansionLineNumber(If->getIfLoc()))
return PrecedingIf;
}
return nullptr;
}
void MisleadingIndentationCheck::danglingElseCheck(const SourceManager &SM,
ASTContext *Context,
const IfStmt *If) {
SourceLocation IfLoc = If->getIfLoc();
SourceLocation ElseLoc = If->getElseLoc();
if (IfLoc.isMacroID() || ElseLoc.isMacroID())
return;
if (SM.getExpansionLineNumber(If->getThen()->getEndLoc()) ==
SM.getExpansionLineNumber(ElseLoc))
return;
// Find location of first 'if' in a 'if else if' chain.
for (auto PrecedingIf = getPrecedingIf(SM, Context, If); PrecedingIf;
PrecedingIf = getPrecedingIf(SM, Context, PrecedingIf))
IfLoc = PrecedingIf->getIfLoc();
if (SM.getExpansionColumnNumber(IfLoc) !=
SM.getExpansionColumnNumber(ElseLoc))
diag(ElseLoc, "different indentation for 'if' and corresponding 'else'");
}
void MisleadingIndentationCheck::missingBracesCheck(const SourceManager &SM,
const CompoundStmt *CStmt) {
const static StringRef StmtNames[] = {"if", "for", "while"};
for (unsigned int i = 0; i < CStmt->size() - 1; i++) {
const Stmt *CurrentStmt = CStmt->body_begin()[i];
const Stmt *Inner = nullptr;
int StmtKind = 0;
if (const auto *CurrentIf = dyn_cast<IfStmt>(CurrentStmt)) {
StmtKind = 0;
Inner =
CurrentIf->getElse() ? CurrentIf->getElse() : CurrentIf->getThen();
} else if (const auto *CurrentFor = dyn_cast<ForStmt>(CurrentStmt)) {
StmtKind = 1;
Inner = CurrentFor->getBody();
} else if (const auto *CurrentWhile = dyn_cast<WhileStmt>(CurrentStmt)) {
StmtKind = 2;
Inner = CurrentWhile->getBody();
} else {
continue;
}
if (isa<CompoundStmt>(Inner))
continue;
SourceLocation InnerLoc = Inner->getBeginLoc();
SourceLocation OuterLoc = CurrentStmt->getBeginLoc();
if (InnerLoc.isInvalid() || InnerLoc.isMacroID() || OuterLoc.isInvalid() ||
OuterLoc.isMacroID())
continue;
if (SM.getExpansionLineNumber(InnerLoc) ==
SM.getExpansionLineNumber(OuterLoc))
continue;
const Stmt *NextStmt = CStmt->body_begin()[i + 1];
SourceLocation NextLoc = NextStmt->getBeginLoc();
if (NextLoc.isInvalid() || NextLoc.isMacroID())
continue;
if (SM.getExpansionColumnNumber(InnerLoc) ==
SM.getExpansionColumnNumber(NextLoc)) {
diag(NextLoc, "misleading indentation: statement is indented too deeply");
diag(OuterLoc, "did you mean this line to be inside this '%0'",
DiagnosticIDs::Note)
<< StmtNames[StmtKind];
}
}
}
void MisleadingIndentationCheck::registerMatchers(MatchFinder *Finder) {
Finder->addMatcher(ifStmt(hasElse(stmt())).bind("if"), this);
Finder->addMatcher(
compoundStmt(has(stmt(anyOf(ifStmt(), forStmt(), whileStmt()))))
.bind("compound"),
this);
}
void MisleadingIndentationCheck::check(const MatchFinder::MatchResult &Result) {
if (const auto *If = Result.Nodes.getNodeAs<IfStmt>("if"))
danglingElseCheck(*Result.SourceManager, Result.Context, If);
if (const auto *CStmt = Result.Nodes.getNodeAs<CompoundStmt>("compound"))
missingBracesCheck(*Result.SourceManager, CStmt);
}
} // namespace readability
} // namespace tidy
} // namespace clang
|