+global\JSParser::Expression()

Complexity

Conditions	135
Paths	371

Size

Total Lines

385

Duplication

Lines	48
Ratio	12.47 %

Importance

Changes

0

<?php
	private function Expression($x, $stop=false)
	{
		$operators = array();
		$operands = array();
		$n = false;

		$bl = $x->bracketLevel;
		$cl = $x->curlyLevel;
		$pl = $x->parenLevel;
		$hl = $x->hookLevel;

		while (($tt = $this->t->get()) != TOKEN_END)
		{
			if ($tt == $stop &&
				$x->bracketLevel == $bl &&
				$x->curlyLevel == $cl &&
				$x->parenLevel == $pl &&
				$x->hookLevel == $hl
			)
			{
				// Stop only if tt matches the optional stop parameter, and that
				// token is not quoted by some kind of bracket.
				break;
			}

			switch ($tt)
			{
				case OP_SEMICOLON:
					// NB: cannot be empty, Statement handled that.
					break 2;

				case OP_HOOK:
					if ($this->t->scanOperand)
						break 2;

					while (	!empty($operators) &&
						$this->opPrecedence[end($operators)->type] > $this->opPrecedence[$tt]
					)
						$this->reduce($operators, $operands);

					array_push($operators, new JSNode($this->t));

					++$x->hookLevel;
					$this->t->scanOperand = true;
					$n = $this->Expression($x);

					if (!$this->t->match(OP_COLON))
						break 2;

					--$x->hookLevel;
					array_push($operands, $n);
				break;

				case OP_COLON:
					if ($x->hookLevel)
						break 2;

					throw $this->t->newSyntaxError('Invalid label');
				break;

break; does not seem to be reachable.

				case OP_ASSIGN:
					if ($this->t->scanOperand)
						break 2;

					// Use >, not >=, for right-associative ASSIGN
					while (	!empty($operators) &&
						$this->opPrecedence[end($operators)->type] > $this->opPrecedence[$tt]
					)
						$this->reduce($operators, $operands);

					array_push($operators, new JSNode($this->t));
					end($operands)->assignOp = $this->t->currentToken()->assignOp;
					$this->t->scanOperand = true;
				break;

				case KEYWORD_IN:
					// An in operator should not be parsed if we're parsing the head of
					// a for (...) loop, unless it is in the then part of a conditional
					// expression, or parenthesized somehow.
					if ($x->inForLoopInit && !$x->hookLevel &&
						!$x->bracketLevel && !$x->curlyLevel &&
						!$x->parenLevel
					)
						break 2;
				// FALL THROUGH
				case OP_COMMA:
					// A comma operator should not be parsed if we're parsing the then part
					// of a conditional expression unless it's parenthesized somehow.
					if ($tt == OP_COMMA && $x->hookLevel &&
						!$x->bracketLevel && !$x->curlyLevel &&
						!$x->parenLevel
					)
						break 2;
				// Treat comma as left-associative so reduce can fold left-heavy
				// COMMA trees into a single array.
				// FALL THROUGH
				case OP_OR:
				case OP_AND:
				case OP_BITWISE_OR:
				case OP_BITWISE_XOR:
				case OP_BITWISE_AND:
				case OP_EQ: case OP_NE: case OP_STRICT_EQ: case OP_STRICT_NE:
				case OP_LT: case OP_LE: case OP_GE: case OP_GT:
				case KEYWORD_INSTANCEOF:
				case OP_LSH: case OP_RSH: case OP_URSH:
				case OP_PLUS: case OP_MINUS:
				case OP_MUL: case OP_DIV: case OP_MOD:
				case OP_DOT:
					if ($this->t->scanOperand)
						break 2;

					while (	!empty($operators) &&
						$this->opPrecedence[end($operators)->type] >= $this->opPrecedence[$tt]
					)
						$this->reduce($operators, $operands);

					if ($tt == OP_DOT)
					{
						$this->t->mustMatch(TOKEN_IDENTIFIER);
						array_push($operands, new JSNode($this->t, OP_DOT, array_pop($operands), new JSNode($this->t)));
					}
					else
					{
						array_push($operators, new JSNode($this->t));
						$this->t->scanOperand = true;
					}
				break;

				case KEYWORD_DELETE: case KEYWORD_VOID: case KEYWORD_TYPEOF:
				case OP_NOT: case OP_BITWISE_NOT: case OP_UNARY_PLUS: case OP_UNARY_MINUS:
				case KEYWORD_NEW:
					if (!$this->t->scanOperand)
						break 2;

					array_push($operators, new JSNode($this->t));
				break;

				case OP_INCREMENT: case OP_DECREMENT:
					if ($this->t->scanOperand)
					{
						array_push($operators, new JSNode($this->t));  // prefix increment or decrement
					}
					else
					{
						// Don't cross a line boundary for postfix {in,de}crement.
						$t = $this->t->tokens[($this->t->tokenIndex + $this->t->lookahead - 1) & 3];
						if ($t && $t->lineno != $this->t->lineno)
							break 2;

						if (!empty($operators))
						{
							// Use >, not >=, so postfix has higher precedence than prefix.
							while ($this->opPrecedence[end($operators)->type] > $this->opPrecedence[$tt])
								$this->reduce($operators, $operands);
						}

						$n = new JSNode($this->t, $tt, array_pop($operands));
						$n->postfix = true;
						array_push($operands, $n);
					}
				break;

				case KEYWORD_FUNCTION:
					if (!$this->t->scanOperand)
						break 2;

					array_push($operands, $this->FunctionDefinition($x, false, EXPRESSED_FORM));
					$this->t->scanOperand = false;
				break;

				case KEYWORD_NULL: case KEYWORD_THIS: case KEYWORD_TRUE: case KEYWORD_FALSE:
				case TOKEN_IDENTIFIER: case TOKEN_NUMBER: case TOKEN_STRING: case TOKEN_REGEXP:
					if (!$this->t->scanOperand)
						break 2;

					array_push($operands, new JSNode($this->t));
					$this->t->scanOperand = false;
				break;

				case TOKEN_CONDCOMMENT_START:
				case TOKEN_CONDCOMMENT_END:
					if ($this->t->scanOperand)
						array_push($operators, new JSNode($this->t));
					else
						array_push($operands, new JSNode($this->t));
				break;

				case OP_LEFT_BRACKET:
					if ($this->t->scanOperand)
					{
						// Array initialiser.  Parse using recursive descent, as the
						// sub-grammar here is not an operator grammar.
						$n = new JSNode($this->t, JS_ARRAY_INIT);
						while (($tt = $this->t->peek()) != OP_RIGHT_BRACKET)
						{
							if ($tt == OP_COMMA)
							{
								$this->t->get();
								$n->addNode(null);
								continue;
							}

							$n->addNode($this->Expression($x, OP_COMMA));

OP_COMMA is of type string, but the function expects a boolean.

							if (!$this->t->match(OP_COMMA))
								break;
						}

						$this->t->mustMatch(OP_RIGHT_BRACKET);
						array_push($operands, $n);
						$this->t->scanOperand = false;
					}
					else
					{
						// Property indexing operator.
						array_push($operators, new JSNode($this->t, JS_INDEX));
						$this->t->scanOperand = true;
						++$x->bracketLevel;
					}
				break;

				case OP_RIGHT_BRACKET:
					if ($this->t->scanOperand || $x->bracketLevel == $bl)
						break 2;

					while ($this->reduce($operators, $operands)->type != JS_INDEX)
						continue;

					--$x->bracketLevel;
				break;

				case OP_LEFT_CURLY:
					if (!$this->t->scanOperand)
						break 2;

					// Object initialiser.  As for array initialisers (see above),
					// parse using recursive descent.
					++$x->curlyLevel;
					$n = new JSNode($this->t, JS_OBJECT_INIT);
					while (!$this->t->match(OP_RIGHT_CURLY))
					{
						do
						{
							$tt = $this->t->get();
							$tv = $this->t->currentToken()->value;
							if (($tv == 'get' || $tv == 'set') && $this->t->peek() == TOKEN_IDENTIFIER)
							{
								if ($x->ecmaStrictMode)
									throw $this->t->newSyntaxError('Illegal property accessor');

								$n->addNode($this->FunctionDefinition($x, true, EXPRESSED_FORM));
							}
							else
							{
								switch ($tt)
								{
									case TOKEN_IDENTIFIER:
									case TOKEN_NUMBER:
									case TOKEN_STRING:
										$id = new JSNode($this->t);
									break;

									case OP_RIGHT_CURLY:
										if ($x->ecmaStrictMode)
											throw $this->t->newSyntaxError('Illegal trailing ,');
									break 3;

									default:
										throw $this->t->newSyntaxError('Invalid property name');
								}

								$this->t->mustMatch(OP_COLON);
								$n->addNode(new JSNode($this->t, JS_PROPERTY_INIT, $id, $this->Expression($x, OP_COMMA)));

OP_COMMA is of type string, but the function expects a boolean.

							}
						}
						while ($this->t->match(OP_COMMA));

						$this->t->mustMatch(OP_RIGHT_CURLY);
						break;
					}

					array_push($operands, $n);
					$this->t->scanOperand = false;
					--$x->curlyLevel;
				break;

				case OP_RIGHT_CURLY:
					if (!$this->t->scanOperand && $x->curlyLevel != $cl)
						throw new Exception('PANIC: right curly botch');
				break 2;

				case OP_LEFT_PAREN:
					if ($this->t->scanOperand)
					{
						array_push($operators, new JSNode($this->t, JS_GROUP));
					}
					else
					{
						while (	!empty($operators) &&
							$this->opPrecedence[end($operators)->type] > $this->opPrecedence[KEYWORD_NEW]
						)
							$this->reduce($operators, $operands);

						// Handle () now, to regularize the n-ary case for n > 0.
						// We must set scanOperand in case there are arguments and
						// the first one is a regexp or unary+/-.
						$n = end($operators);
						$this->t->scanOperand = true;
						if ($this->t->match(OP_RIGHT_PAREN))
						{
							if ($n && $n->type == KEYWORD_NEW)
							{
								array_pop($operators);
								$n->addNode(array_pop($operands));
							}
							else
							{
								$n = new JSNode($this->t, JS_CALL, array_pop($operands), new JSNode($this->t, JS_LIST));
							}

							array_push($operands, $n);
							$this->t->scanOperand = false;
							break;
						}

						if ($n && $n->type == KEYWORD_NEW)
							$n->type = JS_NEW_WITH_ARGS;
						else
							array_push($operators, new JSNode($this->t, JS_CALL));
					}

					++$x->parenLevel;
				break;

				case OP_RIGHT_PAREN:
					if ($this->t->scanOperand || $x->parenLevel == $pl)
						break 2;

					while (($tt = $this->reduce($operators, $operands)->type) != JS_GROUP &&
						$tt != JS_CALL && $tt != JS_NEW_WITH_ARGS
					)
					{
						continue;
					}

					if ($tt != JS_GROUP)
					{
						$n = end($operands);
						if ($n->treeNodes[1]->type != OP_COMMA)
							$n->treeNodes[1] = new JSNode($this->t, JS_LIST, $n->treeNodes[1]);
						else
							$n->treeNodes[1]->type = JS_LIST;
					}

					--$x->parenLevel;
				break;

				// Automatic semicolon insertion means we may scan across a newline
				// and into the beginning of another statement.  If so, break out of
				// the while loop and let the t.scanOperand logic handle errors.
				default:
					break 2;
			}
		}

		if ($x->hookLevel != $hl)
			throw $this->t->newSyntaxError('Missing : in conditional expression');

		if ($x->parenLevel != $pl)
			throw $this->t->newSyntaxError('Missing ) in parenthetical');

		if ($x->bracketLevel != $bl)
			throw $this->t->newSyntaxError('Missing ] in index expression');

		if ($this->t->scanOperand)
			throw $this->t->newSyntaxError('Missing operand');

		// Resume default mode, scanning for operands, not operators.
		$this->t->scanOperand = true;
		$this->t->unget();

		while (count($operators))
			$this->reduce($operators, $operands);

		return array_pop($operands);
	}