clang-tools 8.0.0

CodeComplete.h
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1 //===--- CodeComplete.h ------------------------------------------*- C++-*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Code completion provides suggestions for what the user might type next.
11 // After "std::string S; S." we might suggest members of std::string.
12 // Signature help describes the parameters of a function as you type them.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_CODECOMPLETE_H
17 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_CODECOMPLETE_H
18
19 #include "ClangdUnit.h"
20 #include "Headers.h"
21 #include "Logger.h"
22 #include "Path.h"
23 #include "Protocol.h"
24 #include "index/Index.h"
25 #include "clang/Frontend/PrecompiledPreamble.h"
26 #include "clang/Sema/CodeCompleteConsumer.h"
27 #include "clang/Sema/CodeCompleteOptions.h"
28 #include "clang/Tooling/CompilationDatabase.h"
29 #include "llvm/ADT/Optional.h"
30 #include "llvm/ADT/SmallVector.h"
31 #include "llvm/ADT/StringRef.h"
32 #include "llvm/Support/Error.h"
33 #include <future>
34
35 namespace clang {
36 class NamedDecl;
37 class PCHContainerOperations;
38 namespace clangd {
39
40 struct CodeCompleteOptions {
41 /// Returns options that can be passed to clang's completion engine.
42 clang::CodeCompleteOptions getClangCompleteOpts() const;
43
44 /// When true, completion items will contain expandable code snippets in
45 /// completion (e.g. `return ${1:expression}` or `foo(${1:int a}, ${2:int
46 /// b})).
47 bool EnableSnippets = false;
48
49 /// Add code patterns to completion results.
50 /// If EnableSnippets is false, this options is ignored and code patterns will
51 /// always be omitted.
52 bool IncludeCodePatterns = true;
53
54 /// Add macros to code completion results.
55 bool IncludeMacros = true;
56
57 /// Add comments to code completion results, if available.
58 bool IncludeComments = true;
59
60 /// Include results that are not legal completions in the current context.
61 /// For example, private members are usually inaccessible.
62 bool IncludeIneligibleResults = false;
63
64 /// Combine overloads into a single completion item where possible.
65 bool BundleOverloads = false;
66
67 /// Limit the number of results returned (0 means no limit).
68 /// If more results are available, we set CompletionList.isIncomplete.
69 size_t Limit = 0;
70
71 /// A visual indicator to prepend to the completion label to indicate whether
72 /// completion result would trigger an #include insertion or not.
73 struct IncludeInsertionIndicator {
74 std::string Insert = "•";
75 std::string NoInsert = " ";
76 } IncludeIndicator;
77
78 /// Expose origins of completion items in the label (for debugging).
79 bool ShowOrigins = false;
80
81 /// If set to true, this will send an asynchronous speculative index request,
82 /// based on the index request for the last code completion on the same file
83 /// and the filter text typed before the cursor, before sema code completion
84 /// is invoked. This can reduce the code completion latency (by roughly
85 /// latency of sema code completion) if the speculative request is the same as
86 /// the one generated for the ongoing code completion from sema. As a sequence
87 /// of code completions often have the same scopes and proximity paths etc,
88 /// this should be effective for a number of code completions.
89 bool SpeculativeIndexRequest = false;
90
91 // Populated internally by clangd, do not set.
92 /// If `Index` is set, it is used to augment the code completion
93 /// results.
94 /// FIXME(ioeric): we might want a better way to pass the index around inside
95 /// clangd.
96 const SymbolIndex *Index = nullptr;
97
98 /// Include completions that require small corrections, e.g. change '.' to
99 /// '->' on member access etc.
100 bool IncludeFixIts = false;
101
102 /// Whether to generate snippets for function arguments on code-completion.
103 /// Needs snippets to be enabled as well.
104 bool EnableFunctionArgSnippets = true;
105
106 /// Whether to include index symbols that are not defined in the scopes
107 /// visible from the code completion point. This applies in contexts without
108 /// explicit scope qualifiers.
109 ///
110 /// Such completions can insert scope qualifiers.
111 bool AllScopes = false;
112 };
113
114 // Semi-structured representation of a code-complete suggestion for our C++ API.
115 // We don't use the LSP structures here (unlike most features) as we want
116 // to expose more data to allow for more precise testing and evaluation.
117 struct CodeCompletion {
118 // The unqualified name of the symbol or other completion item.
119 std::string Name;
120 // The scope qualifier for the symbol name. e.g. "ns1::ns2::"
121 // Empty for non-symbol completions. Not inserted, but may be displayed.
122 std::string Scope;
123 // Text that must be inserted before the name, and displayed (e.g. base::).
124 std::string RequiredQualifier;
125 // Details to be displayed following the name. Not inserted.
126 std::string Signature;
127 // Text to be inserted following the name, in snippet format.
128 std::string SnippetSuffix;
129 // Type to be displayed for this completion.
130 std::string ReturnType;
131 std::string Documentation;
132 CompletionItemKind Kind = CompletionItemKind::Missing;
133 // This completion item may represent several symbols that can be inserted in
134 // the same way, such as function overloads. In this case BundleSize > 1, and
135 // the following fields are summaries:
136 // - Signature is e.g. "(...)" for functions.
137 // - SnippetSuffix is similarly e.g. "(${0})".
138 // - ReturnType may be empty
139 // - Documentation may be from one symbol, or a combination of several
140 // Other fields should apply equally to all bundled completions.
141 unsigned BundleSize = 1;
142 SymbolOrigin Origin = SymbolOrigin::Unknown;
143
144 struct IncludeCandidate {
145 // The header through which this symbol could be included.
146 // Quoted string as expected by an #include directive, e.g. "<memory>".
147 // Empty for non-symbol completions, or when not known.
148 std::string Header;
149 // Present if Header should be inserted to use this item.
150 llvm::Optional<TextEdit> Insertion;
151 };
152 // All possible include headers ranked by preference. By default, the first
153 // include is used.
154 // If we've bundled together overloads that have different sets of includes,
155 // thse includes may not be accurate for all of them.
156 llvm::SmallVector<IncludeCandidate, 1> Includes;
157
158 /// Holds information about small corrections that needs to be done. Like
159 /// converting '->' to '.' on member access.
160 std::vector<TextEdit> FixIts;
161
162 /// Holds the range of the token we are going to replace with this completion.
163 Range CompletionTokenRange;
164
165 // Scores are used to rank completion items.
166 struct Scores {
167 // The score that items are ranked by.
168 float Total = 0.f;
169
170 // The finalScore with the fuzzy name match score excluded.
171 // When filtering client-side, editors should calculate the new fuzzy score,
172 // whose scale is 0-1 (with 1 = prefix match, special case 2 = exact match),
173 // and recompute finalScore = fuzzyScore * symbolScore.
174 float ExcludingName = 0.f;
175
176 // Component scores that contributed to the final score:
177
178 // Quality describes how important we think this candidate is,
179 // independent of the query.
180 // e.g. symbols with lots of incoming references have higher quality.
181 float Quality = 0.f;
182 // Relevance describes how well this candidate matched the query.
183 // e.g. symbols from nearby files have higher relevance.
184 float Relevance = 0.f;
185 };
186 Scores Score;
187
188 /// Indicates if this item is deprecated.
189 bool Deprecated = false;
190
191 // Serialize this to an LSP completion item. This is a lossy operation.
192 CompletionItem render(const CodeCompleteOptions &) const;
193 };
194 raw_ostream &operator<<(raw_ostream &, const CodeCompletion &);
195 struct CodeCompleteResult {
196 std::vector<CodeCompletion> Completions;
197 bool HasMore = false;
198 CodeCompletionContext::Kind Context = CodeCompletionContext::CCC_Other;
199 };
200 raw_ostream &operator<<(raw_ostream &, const CodeCompleteResult &);
201
202 /// A speculative and asynchronous fuzzy find index request (based on cached
203 /// request) that can be sent before parsing sema. This would reduce completion
204 /// latency if the speculation succeeds.
205 struct SpeculativeFuzzyFind {
206 /// A cached request from past code completions.
207 /// Set by caller of `codeComplete()`.
208 llvm::Optional<FuzzyFindRequest> CachedReq;
209 /// The actual request used by `codeComplete()`.
210 /// Set by `codeComplete()`. This can be used by callers to update cache.
211 llvm::Optional<FuzzyFindRequest> NewReq;
212 /// The result is consumed by `codeComplete()` if speculation succeeded.
213 /// NOTE: the destructor will wait for the async call to finish.
214 std::future<SymbolSlab> Result;
215 };
216
217 /// Get code completions at a specified \p Pos in \p FileName.
218 /// If \p SpecFuzzyFind is set, a speculative and asynchronous fuzzy find index
219 /// request (based on cached request) will be run before parsing sema. In case
220 /// the speculative result is used by code completion (e.g. speculation failed),
221 /// the speculative result is not consumed, and `SpecFuzzyFind` is only
222 /// destroyed when the async request finishes.
223 CodeCompleteResult codeComplete(PathRef FileName,
224 const tooling::CompileCommand &Command,
225 const PreambleData *Preamble,
226 StringRef Contents, Position Pos,
227 IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
228 std::shared_ptr<PCHContainerOperations> PCHs,
229 CodeCompleteOptions Opts,
230 SpeculativeFuzzyFind *SpecFuzzyFind = nullptr);
231
232 /// Get signature help at a specified \p Pos in \p FileName.
233 SignatureHelp signatureHelp(PathRef FileName,
234 const tooling::CompileCommand &Command,
235 const PreambleData *Preamble, StringRef Contents,
236 Position Pos,
237 IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
238 std::shared_ptr<PCHContainerOperations> PCHs,
239 const SymbolIndex *Index);
240
241 // For index-based completion, we only consider:
242 // * symbols in namespaces or translation unit scopes (e.g. no class
243 // members, no locals)
244 // * enum constants in unscoped enum decl (e.g. "red" in "enum {red};")
245 // * primary templates (no specializations)
246 // For the other cases, we let Clang do the completion because it does not
247 // need any non-local information and it will be much better at following
248 // lookup rules. Other symbols still appear in the index for other purposes,
249 // like workspace/symbols or textDocument/definition, but are not used for code
250 // completion.
251 bool isIndexedForCodeCompletion(const NamedDecl &ND, ASTContext &ASTCtx);
252
253 /// Retrives a speculative code completion filter text before the cursor.
254 /// Exposed for testing only.
255 llvm::Expected<llvm::StringRef>
256 speculateCompletionFilter(llvm::StringRef Content, Position Pos);
257
258 } // namespace clangd
259 } // namespace clang
260
261 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANGD_CODECOMPLETE_H
clang::clangd::SpeculativeFuzzyFind::Result
std::future< SymbolSlab > Result
The result is consumed by codeComplete() if speculation succeeded.
Definition: CodeComplete.h:214
clang::clangd::CodeCompleteOptions::ShowOrigins
bool ShowOrigins
Expose origins of completion items in the label (for debugging).
Definition: CodeComplete.h:79
clang::clangd::signatureHelp
SignatureHelp signatureHelp(PathRef FileName, const tooling::CompileCommand &Command, const PreambleData *Preamble, llvm::StringRef Contents, Position Pos, llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS, std::shared_ptr< PCHContainerOperations > PCHs, const SymbolIndex *Index)
Definition: CodeComplete.cpp:1628
Command
const tooling::CompileCommand & Command
Definition: CodeComplete.cpp:1005
clang::clangd::CodeCompleteOptions::BundleOverloads
bool BundleOverloads
Combine overloads into a single completion item where possible.
Definition: CodeComplete.h:65
clang::clangd::CodeCompletion::Signature
std::string Signature
Definition: CodeComplete.h:126
clang::clangd::CodeCompleteOptions::Limit
size_t Limit
Limit the number of results returned (0 means no limit).
Definition: CodeComplete.h:69
clang::clangd::codeComplete
CodeCompleteResult codeComplete(PathRef FileName, const tooling::CompileCommand &Command, const PreambleData *Preamble, llvm::StringRef Contents, Position Pos, llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS, std::shared_ptr< PCHContainerOperations > PCHs, CodeCompleteOptions Opts, SpeculativeFuzzyFind *SpecFuzzyFind)
Definition: CodeComplete.cpp:1617
Quality
SignatureQualitySignals Quality
Definition: CodeComplete.cpp:809
Contents
llvm::StringRef Contents
Definition: CodeComplete.cpp:1007
Index.h
VFS
llvm::IntrusiveRefCntPtr< llvm::vfs::FileSystem > VFS
Definition: CodeComplete.cpp:1009
clang::clangd::CodeCompleteResult
Definition: CodeComplete.h:195
clang::clangd::CodeCompletion::Scores
Definition: CodeComplete.h:166
clang::clangd::CodeCompleteOptions::EnableSnippets
bool EnableSnippets
When true, completion items will contain expandable code snippets in completion (e.g.
Definition: CodeComplete.h:47
clang::clangd::CompletionItem
Definition: Protocol.h:842
clang::clangd::CodeCompleteResult::Completions
std::vector< CodeCompletion > Completions
Definition: CodeComplete.h:196
clang::clangd::SymbolIndex
Interface for symbol indexes that can be used for searching or matching symbols among a set of symbol...
Definition: Index.h:487
Protocol.h
clang::clangd::Position
Definition: Protocol.h:125
clang::clangd::PathRef
llvm::StringRef PathRef
A typedef to represent a ref to file path.
Definition: Path.h:24
clang::clangd::CodeCompletion::SnippetSuffix
std::string SnippetSuffix
Definition: CodeComplete.h:128
clang::clangd::CodeCompletion::Name
std::string Name
Definition: CodeComplete.h:119
clang::clangd::speculateCompletionFilter
llvm::Expected< llvm::StringRef > speculateCompletionFilter(llvm::StringRef Content, Position Pos)
Retrives a speculative code completion filter text before the cursor.
Definition: CodeComplete.cpp:1592
clang::clangd::CodeCompletion::ReturnType
std::string ReturnType
Definition: CodeComplete.h:130
ClangdUnit.h
clang::clangd::CodeCompletion::IncludeCandidate::Insertion
llvm::Optional< TextEdit > Insertion
Definition: CodeComplete.h:150
clang::clangd::CodeCompleteOptions::IncludeInsertionIndicator::Insert
std::string Insert
Definition: CodeComplete.h:74
Headers.h
clang::clangd::CompletionItemKind
CompletionItemKind
The kind of a completion entry.
Definition: Protocol.h:259
Kind
BindArgumentKind Kind
Definition: AvoidBindCheck.cpp:41
clang::clangd::SpeculativeFuzzyFind::CachedReq
llvm::Optional< FuzzyFindRequest > CachedReq
A cached request from past code completions.
Definition: CodeComplete.h:208
clang::clangd::CodeCompletion::Documentation
std::string Documentation
Definition: CodeComplete.h:131
clang::clangd::CodeCompleteOptions::IncludeFixIts
bool IncludeFixIts
Include completions that require small corrections, e.g.
Definition: CodeComplete.h:100
clang::clangd::CompletionItemKind::Missing
clang::clangd::CodeCompleteOptions::IncludeComments
bool IncludeComments
Add comments to code completion results, if available.
Definition: CodeComplete.h:58
clang::clangd::CodeCompletion::Score
Scores Score
Definition: CodeComplete.h:186
clang::clangd::CodeCompleteOptions::IncludeCodePatterns
bool IncludeCodePatterns
Add code patterns to completion results.
Definition: CodeComplete.h:52
clang::clangd::Range
Definition: Protocol.h:154
clang::clangd::isIndexedForCodeCompletion
bool isIndexedForCodeCompletion(const NamedDecl &ND, ASTContext &ASTCtx)
Definition: CodeComplete.cpp:1650
clang::clangd::CodeCompleteOptions::SpeculativeIndexRequest
bool SpeculativeIndexRequest
If set to true, this will send an asynchronous speculative index request, based on the index request ...
Definition: CodeComplete.h:89
clang::clangd::SpeculativeFuzzyFind
A speculative and asynchronous fuzzy find index request (based on cached request) that can be sent be...
Definition: CodeComplete.h:205
clang::clangd::CodeCompletion::Scope
std::string Scope
Definition: CodeComplete.h:122
clang::clangd::CodeCompleteOptions::IncludeInsertionIndicator
A visual indicator to prepend to the completion label to indicate whether completion result would tri...
Definition: CodeComplete.h:73
clang::clangd::CodeCompletion::Includes
llvm::SmallVector< IncludeCandidate, 1 > Includes
Definition: CodeComplete.h:156
clang::clangd::CodeCompleteOptions
Definition: CodeComplete.h:40
clang::clangd::CodeCompleteOptions::IncludeIneligibleResults
bool IncludeIneligibleResults
Include results that are not legal completions in the current context.
Definition: CodeComplete.h:62
clang::clangd::SpeculativeFuzzyFind::NewReq
llvm::Optional< FuzzyFindRequest > NewReq
The actual request used by codeComplete().
Definition: CodeComplete.h:211
FileName
PathRef FileName
Definition: CodeComplete.cpp:1004
clang::clangd::Context
A context is an immutable container for per-request data that must be propagated through layers that ...
Definition: Context.h:70
clang::clangd::CodeCompleteOptions::getClangCompleteOpts
clang::CodeCompleteOptions getClangCompleteOpts() const
Returns options that can be passed to clang&#39;s completion engine.
Definition: CodeComplete.cpp:1571
clang::clangd::CodeCompletion::IncludeCandidate
Definition: CodeComplete.h:144
Pos
Position Pos
Definition: CodeComplete.cpp:1008
clang::clangd::CodeCompleteOptions::Index
const SymbolIndex * Index
If Index is set, it is used to augment the code completion results.
Definition: CodeComplete.h:96
Logger.h
clang::clangd::SignatureHelp
Represents the signature of a callable.
Definition: Protocol.h:939
Preamble
const PreambleData * Preamble
Definition: CodeComplete.cpp:1006
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ChangeNamespace.cpp:18
Path.h
PCHs
std::shared_ptr< PCHContainerOperations > PCHs
Definition: CodeComplete.cpp:1010
clang::clangd::CodeCompleteOptions::IncludeIndicator
struct clang::clangd::CodeCompleteOptions::IncludeInsertionIndicator IncludeIndicator
clang::clangd::CodeCompleteOptions::IncludeMacros
bool IncludeMacros
Add macros to code completion results.
Definition: CodeComplete.h:55
clang::clangd::SymbolOrigin::Unknown
clang::clangd::CodeCompleteOptions::EnableFunctionArgSnippets
bool EnableFunctionArgSnippets
Whether to generate snippets for function arguments on code-completion.
Definition: CodeComplete.h:104
clang::clangd::CodeCompletion::RequiredQualifier
std::string RequiredQualifier
Definition: CodeComplete.h:124
clang::clangd::CodeCompleteOptions::IncludeInsertionIndicator::NoInsert
std::string NoInsert
Definition: CodeComplete.h:75
clang::clangd::CodeCompleteOptions::AllScopes
bool AllScopes
Whether to include index symbols that are not defined in the scopes visible from the code completion ...
Definition: CodeComplete.h:111
clang::clangd::operator<<
llvm::raw_ostream & operator<<(llvm::raw_ostream &OS, const CodeCompletion &C)
Definition: CodeComplete.cpp:1719
clang::clangd::PreambleData
Definition: ClangdUnit.h:47
clang::clangd::CodeCompletion
Definition: CodeComplete.h:117
clang::clangd::SymbolOrigin
SymbolOrigin
Definition: Index.h:126
clang::clangd::CodeCompletion::IncludeCandidate::Header
std::string Header
Definition: CodeComplete.h:148
clang::clangd::CodeCompletion::CompletionTokenRange
Range CompletionTokenRange
Holds the range of the token we are going to replace with this completion.
Definition: CodeComplete.h:163
clang::clangd::CodeCompletion::FixIts
std::vector< TextEdit > FixIts
Holds information about small corrections that needs to be done.
Definition: CodeComplete.h:160