Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
package io.joern.rubysrc2cpg.parser
import io.joern.rubysrc2cpg.parser.RubyLexer.*
import org.antlr.v4.runtime.Recognizer.EOF
trait RegexLiteralHandling { this: RubyLexerBase =>
/* When encountering '/', we need to decide whether this is a binary operator (e.g. `x / y`) or
* a regular expression delimiter (e.g. `/(eu|us)/`) occurrence. Our approach is to look at the
* previously emitted token and decide accordingly.
*/
private val regexTogglingTokens: Set[Int] = Set(
// When '/' occurs after an opening parenthesis, brace or bracket.
LPAREN,
LCURLY,
LBRACK,
// When '/' occurs after a NL.
NL,
// When '/' occurs after a ','.
COMMA,
// When '/' occurs after a ':'.
COLON,
// When '/' occurs after 'when'.
WHEN,
// When '/' occurs after 'unless'.
UNLESS,
// When '/' occurs after an operator.
EMARK,
EMARKEQ,
EMARKTILDE,
AMP,
AMP2,
AMPDOT,
BAR,
BAR2,
EQ,
EQ2,
EQ3,
CARET,
LTEQGT,
EQGT,
EQTILDE,
GT,
GTEQ,
LT,
LTEQ,
LT2,
GT2,
PLUS,
MINUS,
STAR,
STAR2,
SLASH,
PERCENT,
TILDE,
PLUSAT,
MINUSAT,
ASSIGNMENT_OPERATOR
)
/** To be invoked when encountering `/`, deciding if it should emit a `REGULAR_EXPRESSION_START` token. */
protected def isStartOfRegexLiteral: Boolean = {
val isFirstTokenInTheStream = previousNonWsToken.isEmpty
val isRegexTogglingToken = regexTogglingTokens.contains(previousNonWsTokenTypeOrEOF())
isFirstTokenInTheStream || isRegexTogglingToken || isInCommandArgumentPosition
}
/** Decides if the current `/` is being used as an argument to a command, based on the observation that such literals
* may not start with a WS. E.g. `puts /x/` is valid, but `puts / x/` is not.
*/
private def isInCommandArgumentPosition: Boolean = {
val previousNonWsIsIdentifier =
previousNonWsTokenTypeOrEOF() == LOCAL_VARIABLE_IDENTIFIER || isControlStructureStart
val previousIsWs = previousTokenTypeOrEOF() == WS
val nextCharIsWs = _input.LA(1) == ' '
previousNonWsIsIdentifier && previousIsWs && !nextCharIsWs
}
private def isControlStructureStart: Boolean = {
previousNonWsTokenTypeOrEOF() == IF
|| previousNonWsTokenTypeOrEOF() == UNLESS
|| previousNonWsTokenTypeOrEOF() == UNTIL || previousNonWsTokenTypeOrEOF() == YIELD
|| previousNonWsTokenTypeOrEOF() == WHILE
}
}
