Class DataFlow::DataFlow::Configuration

A global (inter-procedural) data flow configuration.

Each use of the global data flow library must define its own unique extension of this abstract class. A configuration defines a set of relevant sources (isSource) and sinks (isSink), and may additionally prohibit intermediate flow nodes (isBarrier) as well as add custom data flow steps (isAdditionalFlowStep()).

In addition to tracking flow through ordinary callables (for example methods and accessors), the global data flow algorithm tracks flow through delegate calls as well. However, for non-locally resolvable delegate calls the algorithm takes only call contexts of height at most one into account. Example:

public int M(Func<string, int> f, string x) {
  return f(x);
}

M(x => x.Length, ...);

M(_ => 42, ...);

In the body of M on line 2, f can be resolved to the delegates x => x.Length (line 5) and _ => 42 (line 7), requiring different call contexts. The algorithm is able to distinguish which of the two delegates are applicable based on the current call context (that is, if M is called via line 5, only the delegate x => x.Length is applicable, and vice versa for line 7). However, if M is instead defined as:

public int M(Func<string, int> f, string x) {
  return M2(f, x);
}

public int M2(Func<string, int> f, string x) {
  return f(x);
}

M(x => x.Length, ...);

M(_ => 42, ...);

then both delegates from lines 9 and 11 will (incorrectly) be considered valid, as the last call required for resolving f on line 6 is in both cases the call on line 2.

Direct supertypes

Known direct subtypes

Predicates

hasFlow

Holds if data may flow from source to sink for this configuration.

hasFlowPath

Holds if data may flow from source to sink for this configuration.

isAdditionalFlowStep

Holds if the additional flow step from pred to succ must be taken into account in the analysis.

isAdditionalFlowStepIntoCall

INTERNAL: Do not use.

isAdditionalFlowStepOutOfCall

INTERNAL: Do not use.

isBarrier

Holds if the intermediate data flow node node is prohibited.

isSink

Holds if sink is a relevant data flow sink.

isSource

Holds if source is a relevant data flow source.

Inherited predicates

charAt

Returns a one-character string containing the character in the receiver at the given index (which ranges from 0 through length minus one)

from string
indexOf

Returns all the offsets at which the given string occurs in the receiver

from string
indexOf

Returns the index of n’th occurrence of the given string within receiver, starting at the given offset

from string
isLowercase

Holds when the receiver contains no upper-case letters

from string
isUppercase

Holds when the receiver contains no lower-case letters

from string
length

Returns the length of the receiver (in UTF-16 code units)

from string
matches

Holds when the receiver matches the pattern. Patterns are matched by case sensitive string matching, and there are two wildcards: _ matches a single character, and % matches any sequence of characters. To match the actual characters _ or % in the pattern, they must be escaped using backslashes. For example, "anythingstring%".matches("%string\\%") holds.

from string
prefix

Returns the substring of the receiver ending at the given offset

from string
regexpCapture

When the given regexp matches the entire receiver, returns the substring matched by the given capture group

from string
regexpFind

Returns a substring of the receiver which matches the given regexp. Also returns the offset within the receiver at which the match occurred (occurrenceOffset), and the number of matches which occur at smaller offsets (occurrenceIndex)

from string
regexpMatch

Holds when the given regexp matches the entire receiver

from string
regexpReplaceAll

Returns a copy of the receiver with every substring which matches the given regexp is replaced by the replacement

from string
replaceAll

Returns a copy of the receiver with all occurrences of the target replaced by the replacement

from string
splitAt

Returns all of the substrings obtained by splitting the receiver at every occurrence of the argument

from string
splitAt

Returns the n’th substring obtained by splitting the receiver at every occurrence of the argument

from string
substring

Returns the substring of the receiver which starts and ends at the given indices

from string
suffix

Returns the substring of the receiver starting at the given offset

from string
toDate

Returns the date, if any, obtained by parsing the receiver

from string
toFloat

Returns the floating point number, if any, obtained by parsing the receiver

from string
toInt

Returns the integer, if any, obtained by parsing the receiver

from string
toLowerCase

Returns a copy of the receiver with all uppercase characters replaced by lowercase ones

from string
toString

Returns the receiver

from string
toUpperCase

Returns a copy of the receiver with all lowercase characters replaced by uppercase ones

from string
trim

Returns a copy of the receiver with all whitespace removed from the beginning and end of the string (where whitespace is defined as unicode codepoints ‘\u0000’ through ‘\u0020’ inclusive)

from string

Charpred