1 // Copyright (c) 2013 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #include "tools/gn/parse_tree.h" 6 7 #include <string> 8 9 #include "base/stl_util.h" 10 #include "base/strings/string_number_conversions.h" 11 #include "tools/gn/functions.h" 12 #include "tools/gn/operators.h" 13 #include "tools/gn/scope.h" 14 #include "tools/gn/string_utils.h" 15 16 namespace { 17 18 std::string IndentFor(int value) { 19 std::string ret; 20 for (int i = 0; i < value; i++) 21 ret.append(" "); 22 return ret; 23 } 24 25 } // namespace 26 27 ParseNode::ParseNode() { 28 } 29 30 ParseNode::~ParseNode() { 31 } 32 33 const AccessorNode* ParseNode::AsAccessor() const { return NULL; } 34 const BinaryOpNode* ParseNode::AsBinaryOp() const { return NULL; } 35 const BlockNode* ParseNode::AsBlock() const { return NULL; } 36 const ConditionNode* ParseNode::AsConditionNode() const { return NULL; } 37 const FunctionCallNode* ParseNode::AsFunctionCall() const { return NULL; } 38 const IdentifierNode* ParseNode::AsIdentifier() const { return NULL; } 39 const ListNode* ParseNode::AsList() const { return NULL; } 40 const LiteralNode* ParseNode::AsLiteral() const { return NULL; } 41 const UnaryOpNode* ParseNode::AsUnaryOp() const { return NULL; } 42 43 // AccessorNode --------------------------------------------------------------- 44 45 AccessorNode::AccessorNode() { 46 } 47 48 AccessorNode::~AccessorNode() { 49 } 50 51 const AccessorNode* AccessorNode::AsAccessor() const { 52 return this; 53 } 54 55 Value AccessorNode::Execute(Scope* scope, Err* err) const { 56 Value index_value = index_->Execute(scope, err); 57 if (err->has_error()) 58 return Value(); 59 if (!index_value.VerifyTypeIs(Value::INTEGER, err)) 60 return Value(); 61 62 const Value* base_value = scope->GetValue(base_.value(), true); 63 if (!base_value) { 64 *err = MakeErrorDescribing("Undefined identifier."); 65 return Value(); 66 } 67 if (!base_value->VerifyTypeIs(Value::LIST, err)) 68 return Value(); 69 70 int64 index_int = index_value.int_value(); 71 if (index_int < 0) { 72 *err = Err(index_->GetRange(), "Negative array subscript.", 73 "You gave me " + base::Int64ToString(index_int) + "."); 74 return Value(); 75 } 76 size_t index_sizet = static_cast<size_t>(index_int); 77 if (index_sizet >= base_value->list_value().size()) { 78 *err = Err(index_->GetRange(), "Array subscript out of range.", 79 "You gave me " + base::Int64ToString(index_int) + 80 " but I was expecting something from 0 to " + 81 base::Int64ToString( 82 static_cast<int64>(base_value->list_value().size()) - 1) + 83 ", inclusive."); 84 return Value(); 85 } 86 87 // Doing this assumes that there's no way in the language to do anything 88 // between the time the reference is created and the time that the reference 89 // is used. If there is, this will crash! Currently, this is just used for 90 // array accesses where this "shouldn't" happen. 91 return base_value->list_value()[index_sizet]; 92 } 93 94 LocationRange AccessorNode::GetRange() const { 95 return LocationRange(base_.location(), index_->GetRange().end()); 96 } 97 98 Err AccessorNode::MakeErrorDescribing(const std::string& msg, 99 const std::string& help) const { 100 return Err(GetRange(), msg, help); 101 } 102 103 void AccessorNode::Print(std::ostream& out, int indent) const { 104 out << IndentFor(indent) << "ACCESSOR\n"; 105 out << IndentFor(indent + 1) << base_.value() << "\n"; 106 index_->Print(out, indent + 1); 107 } 108 109 // BinaryOpNode --------------------------------------------------------------- 110 111 BinaryOpNode::BinaryOpNode() { 112 } 113 114 BinaryOpNode::~BinaryOpNode() { 115 } 116 117 const BinaryOpNode* BinaryOpNode::AsBinaryOp() const { 118 return this; 119 } 120 121 Value BinaryOpNode::Execute(Scope* scope, Err* err) const { 122 return ExecuteBinaryOperator(scope, this, left_.get(), right_.get(), err); 123 } 124 125 LocationRange BinaryOpNode::GetRange() const { 126 return left_->GetRange().Union(right_->GetRange()); 127 } 128 129 Err BinaryOpNode::MakeErrorDescribing(const std::string& msg, 130 const std::string& help) const { 131 return Err(op_, msg, help); 132 } 133 134 void BinaryOpNode::Print(std::ostream& out, int indent) const { 135 out << IndentFor(indent) << "BINARY(" << op_.value() << ")\n"; 136 left_->Print(out, indent + 1); 137 right_->Print(out, indent + 1); 138 } 139 140 // BlockNode ------------------------------------------------------------------ 141 142 BlockNode::BlockNode(bool has_scope) : has_scope_(has_scope) { 143 } 144 145 BlockNode::~BlockNode() { 146 STLDeleteContainerPointers(statements_.begin(), statements_.end()); 147 } 148 149 const BlockNode* BlockNode::AsBlock() const { 150 return this; 151 } 152 153 Value BlockNode::Execute(Scope* containing_scope, Err* err) const { 154 if (has_scope_) { 155 Scope our_scope(containing_scope); 156 Value ret = ExecuteBlockInScope(&our_scope, err); 157 if (err->has_error()) 158 return Value(); 159 160 // Check for unused vars in the scope. 161 //our_scope.CheckForUnusedVars(err); 162 return ret; 163 } 164 return ExecuteBlockInScope(containing_scope, err); 165 } 166 167 LocationRange BlockNode::GetRange() const { 168 if (begin_token_.type() != Token::INVALID && 169 end_token_.type() != Token::INVALID) { 170 return begin_token_.range().Union(end_token_.range()); 171 } else if (!statements_.empty()) { 172 return statements_[0]->GetRange().Union( 173 statements_[statements_.size() - 1]->GetRange()); 174 } 175 return LocationRange(); 176 } 177 178 Err BlockNode::MakeErrorDescribing(const std::string& msg, 179 const std::string& help) const { 180 return Err(GetRange(), msg, help); 181 } 182 183 void BlockNode::Print(std::ostream& out, int indent) const { 184 out << IndentFor(indent) << "BLOCK\n"; 185 for (size_t i = 0; i < statements_.size(); i++) 186 statements_[i]->Print(out, indent + 1); 187 } 188 189 Value BlockNode::ExecuteBlockInScope(Scope* our_scope, Err* err) const { 190 for (size_t i = 0; i < statements_.size() && !err->has_error(); i++) { 191 // Check for trying to execute things with no side effects in a block. 192 const ParseNode* cur = statements_[i]; 193 if (cur->AsList() || cur->AsLiteral() || cur->AsUnaryOp() || 194 cur->AsIdentifier()) { 195 *err = cur->MakeErrorDescribing( 196 "This statment has no effect.", 197 "Either delete it or do something with the result."); 198 return Value(); 199 } 200 cur->Execute(our_scope, err); 201 } 202 return Value(); 203 } 204 205 // ConditionNode -------------------------------------------------------------- 206 207 ConditionNode::ConditionNode() { 208 } 209 210 ConditionNode::~ConditionNode() { 211 } 212 213 const ConditionNode* ConditionNode::AsConditionNode() const { 214 return this; 215 } 216 217 Value ConditionNode::Execute(Scope* scope, Err* err) const { 218 Value condition_result = condition_->Execute(scope, err); 219 if (err->has_error()) 220 return Value(); 221 if (condition_result.type() != Value::BOOLEAN) { 222 *err = condition_->MakeErrorDescribing( 223 "Condition does not evaluate to a boolean value.", 224 std::string("This is a value of type \"") + 225 Value::DescribeType(condition_result.type()) + 226 "\" instead."); 227 err->AppendRange(if_token_.range()); 228 return Value(); 229 } 230 231 if (condition_result.boolean_value()) { 232 if_true_->ExecuteBlockInScope(scope, err); 233 } else if (if_false_) { 234 // The else block is optional. It's either another condition (for an 235 // "else if" and we can just Execute it and the condition will handle 236 // the scoping) or it's a block indicating an "else" in which ase we 237 // need to be sure it inherits our scope. 238 const BlockNode* if_false_block = if_false_->AsBlock(); 239 if (if_false_block) 240 if_false_block->ExecuteBlockInScope(scope, err); 241 else 242 if_false_->Execute(scope, err); 243 } 244 245 return Value(); 246 } 247 248 LocationRange ConditionNode::GetRange() const { 249 if (if_false_) 250 return if_token_.range().Union(if_false_->GetRange()); 251 return if_token_.range().Union(if_true_->GetRange()); 252 } 253 254 Err ConditionNode::MakeErrorDescribing(const std::string& msg, 255 const std::string& help) const { 256 return Err(if_token_, msg, help); 257 } 258 259 void ConditionNode::Print(std::ostream& out, int indent) const { 260 out << IndentFor(indent) << "CONDITION\n"; 261 condition_->Print(out, indent + 1); 262 if_true_->Print(out, indent + 1); 263 if (if_false_) 264 if_false_->Print(out, indent + 1); 265 } 266 267 // FunctionCallNode ----------------------------------------------------------- 268 269 FunctionCallNode::FunctionCallNode() { 270 } 271 272 FunctionCallNode::~FunctionCallNode() { 273 } 274 275 const FunctionCallNode* FunctionCallNode::AsFunctionCall() const { 276 return this; 277 } 278 279 Value FunctionCallNode::Execute(Scope* scope, Err* err) const { 280 return functions::RunFunction(scope, this, args_.get(), block_.get(), err); 281 } 282 283 LocationRange FunctionCallNode::GetRange() const { 284 if (block_) 285 return function_.range().Union(block_->GetRange()); 286 return function_.range().Union(args_->GetRange()); 287 } 288 289 Err FunctionCallNode::MakeErrorDescribing(const std::string& msg, 290 const std::string& help) const { 291 return Err(function_, msg, help); 292 } 293 294 void FunctionCallNode::Print(std::ostream& out, int indent) const { 295 out << IndentFor(indent) << "FUNCTION(" << function_.value() << ")\n"; 296 args_->Print(out, indent + 1); 297 if (block_) 298 block_->Print(out, indent + 1); 299 } 300 301 // IdentifierNode -------------------------------------------------------------- 302 303 IdentifierNode::IdentifierNode() { 304 } 305 306 IdentifierNode::IdentifierNode(const Token& token) : value_(token) { 307 } 308 309 IdentifierNode::~IdentifierNode() { 310 } 311 312 const IdentifierNode* IdentifierNode::AsIdentifier() const { 313 return this; 314 } 315 316 Value IdentifierNode::Execute(Scope* scope, Err* err) const { 317 const Value* result = scope->GetValue(value_.value(), true); 318 if (!result) { 319 *err = MakeErrorDescribing("Undefined identifier"); 320 return Value(); 321 } 322 return *result; 323 } 324 325 LocationRange IdentifierNode::GetRange() const { 326 return value_.range(); 327 } 328 329 Err IdentifierNode::MakeErrorDescribing(const std::string& msg, 330 const std::string& help) const { 331 return Err(value_, msg, help); 332 } 333 334 void IdentifierNode::Print(std::ostream& out, int indent) const { 335 out << IndentFor(indent) << "IDENTIFIER(" << value_.value() << ")\n"; 336 } 337 338 // ListNode ------------------------------------------------------------------- 339 340 ListNode::ListNode() { 341 } 342 343 ListNode::~ListNode() { 344 STLDeleteContainerPointers(contents_.begin(), contents_.end()); 345 } 346 347 const ListNode* ListNode::AsList() const { 348 return this; 349 } 350 351 Value ListNode::Execute(Scope* scope, Err* err) const { 352 Value result_value(this, Value::LIST); 353 std::vector<Value>& results = result_value.list_value(); 354 results.resize(contents_.size()); 355 356 for (size_t i = 0; i < contents_.size(); i++) { 357 const ParseNode* cur = contents_[i]; 358 results[i] = cur->Execute(scope, err); 359 if (err->has_error()) 360 return Value(); 361 if (results[i].type() == Value::NONE) { 362 *err = cur->MakeErrorDescribing( 363 "This does not evaluate to a value.", 364 "I can't do something with nothing."); 365 return Value(); 366 } 367 } 368 return result_value; 369 } 370 371 LocationRange ListNode::GetRange() const { 372 return LocationRange(begin_token_.location(), end_token_.location()); 373 } 374 375 Err ListNode::MakeErrorDescribing(const std::string& msg, 376 const std::string& help) const { 377 return Err(begin_token_, msg, help); 378 } 379 380 void ListNode::Print(std::ostream& out, int indent) const { 381 out << IndentFor(indent) << "LIST\n"; 382 for (size_t i = 0; i < contents_.size(); i++) 383 contents_[i]->Print(out, indent + 1); 384 } 385 386 // LiteralNode ----------------------------------------------------------------- 387 388 LiteralNode::LiteralNode() { 389 } 390 391 LiteralNode::LiteralNode(const Token& token) : value_(token) { 392 } 393 394 LiteralNode::~LiteralNode() { 395 } 396 397 const LiteralNode* LiteralNode::AsLiteral() const { 398 return this; 399 } 400 401 Value LiteralNode::Execute(Scope* scope, Err* err) const { 402 switch (value_.type()) { 403 case Token::TRUE_TOKEN: 404 return Value(this, true); 405 case Token::FALSE_TOKEN: 406 return Value(this, false); 407 case Token::INTEGER: { 408 int64 result_int; 409 if (!base::StringToInt64(value_.value(), &result_int)) { 410 *err = MakeErrorDescribing("This does not look like an integer"); 411 return Value(); 412 } 413 return Value(this, result_int); 414 } 415 case Token::STRING: { 416 Value v(this, Value::STRING); 417 ExpandStringLiteral(scope, value_, &v, err); 418 return v; 419 } 420 default: 421 NOTREACHED(); 422 return Value(); 423 } 424 } 425 426 LocationRange LiteralNode::GetRange() const { 427 return value_.range(); 428 } 429 430 Err LiteralNode::MakeErrorDescribing(const std::string& msg, 431 const std::string& help) const { 432 return Err(value_, msg, help); 433 } 434 435 void LiteralNode::Print(std::ostream& out, int indent) const { 436 out << IndentFor(indent) << "LITERAL(" << value_.value() << ")\n"; 437 } 438 439 // UnaryOpNode ---------------------------------------------------------------- 440 441 UnaryOpNode::UnaryOpNode() { 442 } 443 444 UnaryOpNode::~UnaryOpNode() { 445 } 446 447 const UnaryOpNode* UnaryOpNode::AsUnaryOp() const { 448 return this; 449 } 450 451 Value UnaryOpNode::Execute(Scope* scope, Err* err) const { 452 Value operand_value = operand_->Execute(scope, err); 453 if (err->has_error()) 454 return Value(); 455 return ExecuteUnaryOperator(scope, this, operand_value, err); 456 } 457 458 LocationRange UnaryOpNode::GetRange() const { 459 return op_.range().Union(operand_->GetRange()); 460 } 461 462 Err UnaryOpNode::MakeErrorDescribing(const std::string& msg, 463 const std::string& help) const { 464 return Err(op_, msg, help); 465 } 466 467 void UnaryOpNode::Print(std::ostream& out, int indent) const { 468 out << IndentFor(indent) << "UNARY(" << op_.value() << ")\n"; 469 operand_->Print(out, indent + 1); 470 } 471