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Wikimedia\Diff\DiffEngine Class Reference
DifferenceEngine

This diff implementation is mainly lifted from the LCS algorithm of the Eclipse project which in turn is based on Myers' "An O(ND) difference algorithm and its variations" (http://citeseer.ist.psu.edu/myers86ond.html) with range compression (see Wu et al. More...

Public Member Functions

 __construct ( $tooLong=2_000_000, $powLimit=1.45)
 
 diff ( $from_lines, $to_lines)
 Performs diff.
 
 getLcsLength ()
 
 setBailoutComplexity ( $value)
 Sets the complexity (in comparison operations) that can't be exceeded.
 

Public Attributes

array $added
 
bool $heuristicUsed
 
int $length
 
array $removed
 

Protected Member Functions

 diffInternal (array $from, array $to)
 

Protected Attributes

int $bailoutComplexity = 0
 

Detailed Description

This diff implementation is mainly lifted from the LCS algorithm of the Eclipse project which in turn is based on Myers' "An O(ND) difference algorithm and its variations" (http://citeseer.ist.psu.edu/myers86ond.html) with range compression (see Wu et al.

's "An O(NP) Sequence Comparison Algorithm").

This implementation supports an upper bound on the execution time.

Some ideas (and a bit of code) are from analyze.c, from GNU diffutils-2.7, which can be found at: ftp://gnudist.gnu.org/pub/gnu/diffutils/diffutils-2.7.tar.gz

Complexity: O((M + N)D) worst case time, O(M + N + D^2) expected time, O(M + N) space

Author
Guy Van den Broeck, Geoffrey T. Dairiki, Tim Starling

Definition at line 34 of file DiffEngine.php.

Constructor & Destructor Documentation

◆ __construct()

Wikimedia\Diff\DiffEngine::__construct ( $tooLong = 2_000_000,
$powLimit = 1.45 )
Parameters
int$tooLong
float$powLimit

Definition at line 74 of file DiffEngine.php.

Member Function Documentation

◆ diff()

Wikimedia\Diff\DiffEngine::diff ( $from_lines,
$to_lines )

Performs diff.

Parameters
string[]$from_lines
string[]$to_lines
Exceptions
ComplexityException
Returns
DiffOp[]

Definition at line 88 of file DiffEngine.php.

References Wikimedia\Diff\DiffEngine\diffInternal().

◆ diffInternal()

Wikimedia\Diff\DiffEngine::diffInternal ( array $from,
array $to )
protected
Parameters
string[]$from
string[]$to
Exceptions
ComplexityException

Definition at line 289 of file DiffEngine.php.

References Wikimedia\Diff\DiffEngine\$added, and Wikimedia\Diff\DiffEngine\$removed.

Referenced by Wikimedia\Diff\DiffEngine\diff().

◆ getLcsLength()

Wikimedia\Diff\DiffEngine::getLcsLength ( )
Returns
int

Definition at line 790 of file DiffEngine.php.

References Wikimedia\Diff\DiffEngine\$length.

◆ setBailoutComplexity()

Wikimedia\Diff\DiffEngine::setBailoutComplexity ( $value)

Sets the complexity (in comparison operations) that can't be exceeded.

Parameters
int$value

Definition at line 145 of file DiffEngine.php.

Referenced by Wikimedia\Diff\Diff\__construct().

Member Data Documentation

◆ $added

array Wikimedia\Diff\DiffEngine::$added

Definition at line 66 of file DiffEngine.php.

Referenced by Wikimedia\Diff\DiffEngine\diffInternal().

◆ $bailoutComplexity

int Wikimedia\Diff\DiffEngine::$bailoutComplexity = 0
protected

Definition at line 52 of file DiffEngine.php.

◆ $heuristicUsed

bool Wikimedia\Diff\DiffEngine::$heuristicUsed

Definition at line 68 of file DiffEngine.php.

◆ $length

int Wikimedia\Diff\DiffEngine::$length

Definition at line 62 of file DiffEngine.php.

Referenced by Wikimedia\Diff\DiffEngine\getLcsLength().

◆ $removed

array Wikimedia\Diff\DiffEngine::$removed

Definition at line 64 of file DiffEngine.php.

Referenced by Wikimedia\Diff\DiffEngine\diffInternal().

The documentation for this class was generated from the following file: