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DiffEngine Class Reference

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=2000000, $powLimit=1.45)
 
 diff ( $from_lines, $to_lines)
 Performs diff. More...
 
 getLcsLength ()
 
 setBailoutComplexity ( $value)
 Sets the complexity (in comparison operations) that can't be exceeded. More...
 

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 47 of file DiffEngine.php.

Constructor & Destructor Documentation

◆ __construct()

DiffEngine::__construct (   $tooLong = 2000000,
  $powLimit = 1.45 
)
Parameters
int$tooLong
float$powLimit

Definition at line 87 of file DiffEngine.php.

Member Function Documentation

◆ diff()

DiffEngine::diff (   $from_lines,
  $to_lines 
)

Performs diff.

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

Definition at line 101 of file DiffEngine.php.

References diffInternal().

◆ diffInternal()

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

Definition at line 302 of file DiffEngine.php.

References $added, $removed, n, and wfDebug().

Referenced by diff().

◆ getLcsLength()

DiffEngine::getLcsLength ( )
Returns
int

Definition at line 804 of file DiffEngine.php.

References $length.

◆ setBailoutComplexity()

DiffEngine::setBailoutComplexity (   $value)

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

Parameters
int$value

Definition at line 158 of file DiffEngine.php.

Referenced by Diff\__construct().

Member Data Documentation

◆ $added

array DiffEngine::$added

Definition at line 79 of file DiffEngine.php.

Referenced by diffInternal().

◆ $bailoutComplexity

int DiffEngine::$bailoutComplexity = 0
protected

Definition at line 65 of file DiffEngine.php.

◆ $heuristicUsed

bool DiffEngine::$heuristicUsed

Definition at line 81 of file DiffEngine.php.

◆ $length

int DiffEngine::$length

Definition at line 75 of file DiffEngine.php.

Referenced by getLcsLength().

◆ $removed

array DiffEngine::$removed

Definition at line 77 of file DiffEngine.php.

Referenced by diffInternal().


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