1 //===---- QueryParser.cpp - clang-query command parser --------------------===//
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 "QueryParser.h"
10 #include "Query.h"
11 #include "QuerySession.h"
12 #include "clang/ASTMatchers/Dynamic/Parser.h"
13 #include "clang/Basic/CharInfo.h"
14 #include "llvm/ADT/StringRef.h"
15 #include "llvm/ADT/StringSwitch.h"
16 #include <set>
17
18 using namespace llvm;
19 using namespace clang::ast_matchers::dynamic;
20
21 namespace clang {
22 namespace query {
23
24 // Lex any amount of whitespace followed by a "word" (any sequence of
25 // non-whitespace characters) from the start of region [Begin,End). If no word
26 // is found before End, return StringRef(). Begin is adjusted to exclude the
27 // lexed region.
lexWord()28 StringRef QueryParser::lexWord() {
29 Line = Line.drop_while([](char c) {
30 // Don't trim newlines.
31 return StringRef(" \t\v\f\r").contains(c);
32 });
33
34 if (Line.empty())
35 // Even though the Line is empty, it contains a pointer and
36 // a (zero) length. The pointer is used in the LexOrCompleteWord
37 // code completion.
38 return Line;
39
40 StringRef Word;
41 if (Line.front() == '#')
42 Word = Line.substr(0, 1);
43 else
44 Word = Line.take_until(isWhitespace);
45
46 Line = Line.drop_front(Word.size());
47 return Word;
48 }
49
50 // This is the StringSwitch-alike used by lexOrCompleteWord below. See that
51 // function for details.
52 template <typename T> struct QueryParser::LexOrCompleteWord {
53 StringRef Word;
54 StringSwitch<T> Switch;
55
56 QueryParser *P;
57 // Set to the completion point offset in Word, or StringRef::npos if
58 // completion point not in Word.
59 size_t WordCompletionPos;
60
61 // Lexes a word and stores it in Word. Returns a LexOrCompleteWord<T> object
62 // that can be used like a llvm::StringSwitch<T>, but adds cases as possible
63 // completions if the lexed word contains the completion point.
LexOrCompleteWordclang::query::QueryParser::LexOrCompleteWord64 LexOrCompleteWord(QueryParser *P, StringRef &OutWord)
65 : Word(P->lexWord()), Switch(Word), P(P),
66 WordCompletionPos(StringRef::npos) {
67 OutWord = Word;
68 if (P->CompletionPos && P->CompletionPos <= Word.data() + Word.size()) {
69 if (P->CompletionPos < Word.data())
70 WordCompletionPos = 0;
71 else
72 WordCompletionPos = P->CompletionPos - Word.data();
73 }
74 }
75
Caseclang::query::QueryParser::LexOrCompleteWord76 LexOrCompleteWord &Case(llvm::StringLiteral CaseStr, const T &Value,
77 bool IsCompletion = true) {
78
79 if (WordCompletionPos == StringRef::npos)
80 Switch.Case(CaseStr, Value);
81 else if (CaseStr.size() != 0 && IsCompletion && WordCompletionPos <= CaseStr.size() &&
82 CaseStr.substr(0, WordCompletionPos) ==
83 Word.substr(0, WordCompletionPos))
84 P->Completions.push_back(LineEditor::Completion(
85 (CaseStr.substr(WordCompletionPos) + " ").str(),
86 std::string(CaseStr)));
87 return *this;
88 }
89
Defaultclang::query::QueryParser::LexOrCompleteWord90 T Default(T Value) { return Switch.Default(Value); }
91 };
92
parseSetBool(bool QuerySession::* Var)93 QueryRef QueryParser::parseSetBool(bool QuerySession::*Var) {
94 StringRef ValStr;
95 unsigned Value = LexOrCompleteWord<unsigned>(this, ValStr)
96 .Case("false", 0)
97 .Case("true", 1)
98 .Default(~0u);
99 if (Value == ~0u) {
100 return new InvalidQuery("expected 'true' or 'false', got '" + ValStr + "'");
101 }
102 return new SetQuery<bool>(Var, Value);
103 }
104
parseSetOutputKind()105 template <typename QueryType> QueryRef QueryParser::parseSetOutputKind() {
106 StringRef ValStr;
107 unsigned OutKind = LexOrCompleteWord<unsigned>(this, ValStr)
108 .Case("diag", OK_Diag)
109 .Case("print", OK_Print)
110 .Case("detailed-ast", OK_DetailedAST)
111 .Case("dump", OK_DetailedAST)
112 .Default(~0u);
113 if (OutKind == ~0u) {
114 return new InvalidQuery(
115 "expected 'diag', 'print', 'detailed-ast' or 'dump', got '" + ValStr +
116 "'");
117 }
118
119 switch (OutKind) {
120 case OK_DetailedAST:
121 return new QueryType(&QuerySession::DetailedASTOutput);
122 case OK_Diag:
123 return new QueryType(&QuerySession::DiagOutput);
124 case OK_Print:
125 return new QueryType(&QuerySession::PrintOutput);
126 }
127
128 llvm_unreachable("Invalid output kind");
129 }
130
parseSetTraversalKind(ast_type_traits::TraversalKind QuerySession::* Var)131 QueryRef QueryParser::parseSetTraversalKind(
132 ast_type_traits::TraversalKind QuerySession::*Var) {
133 StringRef ValStr;
134 unsigned Value =
135 LexOrCompleteWord<unsigned>(this, ValStr)
136 .Case("AsIs", ast_type_traits::TK_AsIs)
137 .Case("IgnoreUnlessSpelledInSource",
138 ast_type_traits::TK_IgnoreUnlessSpelledInSource)
139 .Default(~0u);
140 if (Value == ~0u) {
141 return new InvalidQuery("expected traversal kind, got '" + ValStr + "'");
142 }
143 return new SetQuery<ast_type_traits::TraversalKind>(
144 Var, static_cast<ast_type_traits::TraversalKind>(Value));
145 }
146
endQuery(QueryRef Q)147 QueryRef QueryParser::endQuery(QueryRef Q) {
148 StringRef Extra = Line;
149 StringRef ExtraTrimmed = Extra.drop_while(
150 [](char c) { return StringRef(" \t\v\f\r").contains(c); });
151
152 if ((!ExtraTrimmed.empty() && ExtraTrimmed[0] == '\n') ||
153 (ExtraTrimmed.size() >= 2 && ExtraTrimmed[0] == '\r' &&
154 ExtraTrimmed[1] == '\n'))
155 Q->RemainingContent = Extra;
156 else {
157 StringRef TrailingWord = lexWord();
158 if (!TrailingWord.empty() && TrailingWord.front() == '#') {
159 Line = Line.drop_until([](char c) { return c == '\n'; });
160 Line = Line.drop_while([](char c) { return c == '\n'; });
161 return endQuery(Q);
162 }
163 if (!TrailingWord.empty()) {
164 return new InvalidQuery("unexpected extra input: '" + Extra + "'");
165 }
166 }
167 return Q;
168 }
169
170 namespace {
171
172 enum ParsedQueryKind {
173 PQK_Invalid,
174 PQK_Comment,
175 PQK_NoOp,
176 PQK_Help,
177 PQK_Let,
178 PQK_Match,
179 PQK_Set,
180 PQK_Unlet,
181 PQK_Quit,
182 PQK_Enable,
183 PQK_Disable
184 };
185
186 enum ParsedQueryVariable {
187 PQV_Invalid,
188 PQV_Output,
189 PQV_BindRoot,
190 PQV_PrintMatcher,
191 PQV_Traversal
192 };
193
makeInvalidQueryFromDiagnostics(const Diagnostics & Diag)194 QueryRef makeInvalidQueryFromDiagnostics(const Diagnostics &Diag) {
195 std::string ErrStr;
196 llvm::raw_string_ostream OS(ErrStr);
197 Diag.printToStreamFull(OS);
198 return new InvalidQuery(OS.str());
199 }
200
201 } // namespace
202
completeMatcherExpression()203 QueryRef QueryParser::completeMatcherExpression() {
204 std::vector<MatcherCompletion> Comps = Parser::completeExpression(
205 Line, CompletionPos - Line.begin(), nullptr, &QS.NamedValues);
206 for (auto I = Comps.begin(), E = Comps.end(); I != E; ++I) {
207 Completions.push_back(LineEditor::Completion(I->TypedText, I->MatcherDecl));
208 }
209 return QueryRef();
210 }
211
doParse()212 QueryRef QueryParser::doParse() {
213 StringRef CommandStr;
214 ParsedQueryKind QKind = LexOrCompleteWord<ParsedQueryKind>(this, CommandStr)
215 .Case("", PQK_NoOp)
216 .Case("#", PQK_Comment, /*IsCompletion=*/false)
217 .Case("help", PQK_Help)
218 .Case("l", PQK_Let, /*IsCompletion=*/false)
219 .Case("let", PQK_Let)
220 .Case("m", PQK_Match, /*IsCompletion=*/false)
221 .Case("match", PQK_Match)
222 .Case("q", PQK_Quit, /*IsCompletion=*/false)
223 .Case("quit", PQK_Quit)
224 .Case("set", PQK_Set)
225 .Case("enable", PQK_Enable)
226 .Case("disable", PQK_Disable)
227 .Case("unlet", PQK_Unlet)
228 .Default(PQK_Invalid);
229
230 switch (QKind) {
231 case PQK_Comment:
232 case PQK_NoOp:
233 Line = Line.drop_until([](char c) { return c == '\n'; });
234 Line = Line.drop_while([](char c) { return c == '\n'; });
235 if (Line.empty())
236 return new NoOpQuery;
237 return doParse();
238
239 case PQK_Help:
240 return endQuery(new HelpQuery);
241
242 case PQK_Quit:
243 return endQuery(new QuitQuery);
244
245 case PQK_Let: {
246 StringRef Name = lexWord();
247
248 if (Name.empty())
249 return new InvalidQuery("expected variable name");
250
251 if (CompletionPos)
252 return completeMatcherExpression();
253
254 Diagnostics Diag;
255 ast_matchers::dynamic::VariantValue Value;
256 if (!Parser::parseExpression(Line, nullptr, &QS.NamedValues, &Value,
257 &Diag)) {
258 return makeInvalidQueryFromDiagnostics(Diag);
259 }
260
261 auto *Q = new LetQuery(Name, Value);
262 Q->RemainingContent = Line;
263 return Q;
264 }
265
266 case PQK_Match: {
267 if (CompletionPos)
268 return completeMatcherExpression();
269
270 Diagnostics Diag;
271 auto MatcherSource = Line.ltrim();
272 auto OrigMatcherSource = MatcherSource;
273 Optional<DynTypedMatcher> Matcher = Parser::parseMatcherExpression(
274 MatcherSource, nullptr, &QS.NamedValues, &Diag);
275 if (!Matcher) {
276 return makeInvalidQueryFromDiagnostics(Diag);
277 }
278 auto ActualSource = OrigMatcherSource.slice(0, OrigMatcherSource.size() -
279 MatcherSource.size());
280 auto *Q = new MatchQuery(ActualSource, *Matcher);
281 Q->RemainingContent = MatcherSource;
282 return Q;
283 }
284
285 case PQK_Set: {
286 StringRef VarStr;
287 ParsedQueryVariable Var =
288 LexOrCompleteWord<ParsedQueryVariable>(this, VarStr)
289 .Case("output", PQV_Output)
290 .Case("bind-root", PQV_BindRoot)
291 .Case("print-matcher", PQV_PrintMatcher)
292 .Case("traversal", PQV_Traversal)
293 .Default(PQV_Invalid);
294 if (VarStr.empty())
295 return new InvalidQuery("expected variable name");
296 if (Var == PQV_Invalid)
297 return new InvalidQuery("unknown variable: '" + VarStr + "'");
298
299 QueryRef Q;
300 switch (Var) {
301 case PQV_Output:
302 Q = parseSetOutputKind<SetExclusiveOutputQuery>();
303 break;
304 case PQV_BindRoot:
305 Q = parseSetBool(&QuerySession::BindRoot);
306 break;
307 case PQV_PrintMatcher:
308 Q = parseSetBool(&QuerySession::PrintMatcher);
309 break;
310 case PQV_Traversal:
311 Q = parseSetTraversalKind(&QuerySession::TK);
312 break;
313 case PQV_Invalid:
314 llvm_unreachable("Invalid query kind");
315 }
316
317 return endQuery(Q);
318 }
319 case PQK_Enable:
320 case PQK_Disable: {
321 StringRef VarStr;
322 ParsedQueryVariable Var =
323 LexOrCompleteWord<ParsedQueryVariable>(this, VarStr)
324 .Case("output", PQV_Output)
325 .Default(PQV_Invalid);
326 if (VarStr.empty())
327 return new InvalidQuery("expected variable name");
328 if (Var == PQV_Invalid)
329 return new InvalidQuery("unknown variable: '" + VarStr + "'");
330
331 QueryRef Q;
332
333 if (QKind == PQK_Enable)
334 Q = parseSetOutputKind<EnableOutputQuery>();
335 else if (QKind == PQK_Disable)
336 Q = parseSetOutputKind<DisableOutputQuery>();
337 else
338 llvm_unreachable("Invalid query kind");
339 return endQuery(Q);
340 }
341
342 case PQK_Unlet: {
343 StringRef Name = lexWord();
344
345 if (Name.empty())
346 return new InvalidQuery("expected variable name");
347
348 return endQuery(new LetQuery(Name, VariantValue()));
349 }
350
351 case PQK_Invalid:
352 return new InvalidQuery("unknown command: " + CommandStr);
353 }
354
355 llvm_unreachable("Invalid query kind");
356 }
357
parse(StringRef Line,const QuerySession & QS)358 QueryRef QueryParser::parse(StringRef Line, const QuerySession &QS) {
359 return QueryParser(Line, QS).doParse();
360 }
361
362 std::vector<LineEditor::Completion>
complete(StringRef Line,size_t Pos,const QuerySession & QS)363 QueryParser::complete(StringRef Line, size_t Pos, const QuerySession &QS) {
364 QueryParser P(Line, QS);
365 P.CompletionPos = Line.data() + Pos;
366
367 P.doParse();
368 return P.Completions;
369 }
370
371 } // namespace query
372 } // namespace clang
373