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
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
| //===--- HeaderSourceSwitch.cpp - --------------------------------*- C++-*-===//
//
// 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 "HeaderSourceSwitch.h"
#include "AST.h"
#include "Logger.h"
#include "index/SymbolCollector.h"
#include "clang/AST/Decl.h"
namespace clang {
namespace clangd {
llvm::Optional<Path> getCorrespondingHeaderOrSource(
const Path &OriginalFile,
llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
llvm::StringRef SourceExtensions[] = {".cpp", ".c", ".cc", ".cxx",
".c++", ".m", ".mm"};
llvm::StringRef HeaderExtensions[] = {".h", ".hh", ".hpp", ".hxx", ".inc"};
llvm::StringRef PathExt = llvm::sys::path::extension(OriginalFile);
// Lookup in a list of known extensions.
auto SourceIter =
llvm::find_if(SourceExtensions, [&PathExt](PathRef SourceExt) {
return SourceExt.equals_lower(PathExt);
});
bool IsSource = SourceIter != std::end(SourceExtensions);
auto HeaderIter =
llvm::find_if(HeaderExtensions, [&PathExt](PathRef HeaderExt) {
return HeaderExt.equals_lower(PathExt);
});
bool IsHeader = HeaderIter != std::end(HeaderExtensions);
// We can only switch between the known extensions.
if (!IsSource && !IsHeader)
return None;
// Array to lookup extensions for the switch. An opposite of where original
// extension was found.
llvm::ArrayRef<llvm::StringRef> NewExts;
if (IsSource)
NewExts = HeaderExtensions;
else
NewExts = SourceExtensions;
// Storage for the new path.
llvm::SmallString<128> NewPath = llvm::StringRef(OriginalFile);
// Loop through switched extension candidates.
for (llvm::StringRef NewExt : NewExts) {
llvm::sys::path::replace_extension(NewPath, NewExt);
if (VFS->exists(NewPath))
return NewPath.str().str(); // First str() to convert from SmallString to
// StringRef, second to convert from StringRef
// to std::string
// Also check NewExt in upper-case, just in case.
llvm::sys::path::replace_extension(NewPath, NewExt.upper());
if (VFS->exists(NewPath))
return NewPath.str().str();
}
return None;
}
llvm::Optional<Path> getCorrespondingHeaderOrSource(const Path &OriginalFile,
ParsedAST &AST,
const SymbolIndex *Index) {
if (!Index) {
// FIXME: use the AST to do the inference.
return None;
}
LookupRequest Request;
// Find all symbols present in the original file.
for (const auto *D : getIndexableLocalDecls(AST)) {
if (auto ID = getSymbolID(D))
Request.IDs.insert(*ID);
}
llvm::StringMap<int> Candidates; // Target path => score.
auto AwardTarget = [&](const char *TargetURI) {
if (auto TargetPath = URI::resolve(TargetURI, OriginalFile)) {
if (*TargetPath != OriginalFile) // exclude the original file.
++Candidates[*TargetPath];
} else {
elog("Failed to resolve URI {0}: {1}", TargetURI, TargetPath.takeError());
}
};
// If we switch from a header, we are looking for the implementation
// file, so we use the definition loc; otherwise we look for the header file,
// we use the decl loc;
//
// For each symbol in the original file, we get its target location (decl or
// def) from the index, then award that target file.
bool IsHeader = AST.getASTContext().getLangOpts().IsHeaderFile;
Index->lookup(Request, [&](const Symbol &Sym) {
if (IsHeader)
AwardTarget(Sym.Definition.FileURI);
else
AwardTarget(Sym.CanonicalDeclaration.FileURI);
});
// FIXME: our index doesn't have any interesting information (this could be
// that the background-index is not finished), we should use the decl/def
// locations from the AST to do the inference (from .cc to .h).
if (Candidates.empty())
return None;
// Pickup the winner, who contains most of symbols.
// FIXME: should we use other signals (file proximity) to help score?
auto Best = Candidates.begin();
for (auto It = Candidates.begin(); It != Candidates.end(); ++It) {
if (It->second > Best->second)
Best = It;
else if (It->second == Best->second && It->first() < Best->first())
// Select the first one in the lexical order if we have multiple
// candidates.
Best = It;
}
return Path(Best->first());
}
std::vector<const Decl *> getIndexableLocalDecls(ParsedAST &AST) {
std::vector<const Decl *> Results;
std::function<void(Decl *)> TraverseDecl = [&](Decl *D) {
auto *ND = llvm::dyn_cast<NamedDecl>(D);
if (!ND || ND->isImplicit())
return;
if (!SymbolCollector::shouldCollectSymbol(*ND, D->getASTContext(), {},
/*IsMainFileSymbol=*/false))
return;
if (!llvm::isa<FunctionDecl>(ND)) {
// Visit the children, but we skip function decls as we are not interested
// in the function body.
if (auto *Scope = llvm::dyn_cast<DeclContext>(ND)) {
for (auto *D : Scope->decls())
TraverseDecl(D);
}
}
if (llvm::isa<NamespaceDecl>(D))
return; // namespace is indexable, but we're not interested.
Results.push_back(D);
};
// Traverses the ParsedAST directly to collect all decls present in the main
// file.
for (auto *TopLevel : AST.getLocalTopLevelDecls())
TraverseDecl(TopLevel);
return Results;
}
} // namespace clangd
} // namespace clang
|