X-Git-Url: https://git.lyx.org/gitweb/?a=blobdiff_plain;f=src%2FCompare.cpp;h=32f404736c20e20a0ab92e0b2903acb4efe1aff0;hb=c0f4aa8c4b786dcfb3699b175dff63f109abba98;hp=53ccc5b6d104f35daa55597def4726159f78a631;hpb=d378b5d8ee962a66c28eb4a9f0c4d1be2d4f08f4;p=lyx.git

diff --git a/src/Compare.cpp b/src/Compare.cpp
index 53ccc5b6d1..32f404736c 100644
--- a/src/Compare.cpp
+++ b/src/Compare.cpp
@@ -22,8 +22,6 @@
 
 #include <boost/next_prior.hpp>
 
-#include <cmath>
-
 using namespace std;
 using namespace lyx::support;
 
@@ -446,6 +444,13 @@ static bool equal(Inset const * i_o, Inset const * i_n)
 
 
 static bool equal(DocIterator & o, DocIterator & n) {
+	// Explicitly check for this, so we won't call
+	// Paragraph::getChar for the last pos.
+	bool const o_lastpos = o.pos() == o.lastpos();
+	bool const n_lastpos = n.pos() == n.lastpos();
+	if (o_lastpos || n_lastpos)
+		return o_lastpos && n_lastpos;
+
 	Paragraph const & old_par = o.text()->getPar(o.pit());
 	Paragraph const & new_par = n.text()->getPar(n.pit());
 
@@ -520,6 +525,7 @@ void Compare::Impl::furthestDpathKdiagonal(int D, int k,
 	// Where do we take the step from ?
 	int const kk = vertical_step ? k + 1 : k - 1;
 	DocPair p(op[kk], np[kk]);
+	DocPair const s(os[kk], ns[kk]);
 
 	// If D==0 we simulate a vertical step from (0,-1) by doing nothing.
 	if (D != 0) {
@@ -541,8 +547,8 @@ void Compare::Impl::furthestDpathKdiagonal(int D, int k,
 		ns[k] = p.n;
 	} else {
 		// Copy last snake from the previous step
-		os[k] = os[kk];
-		ns[k] = ns[kk];
+		os[k] = s.o;
+		ns[k] = s.n;
 	}
 
 	//Record new position
@@ -625,9 +631,10 @@ int Compare::Impl::findMiddleSnake(DocRangePair const & rp,
 	ors.reset(DocIterator());
 	nrs.reset(DocIterator());
 
+	// In the formula below, the "+ 1" ensures we round like ceil()
+	int const D_max = (M_ + N_ + 1)/2;
 	// D is the number of horizontal and vertical steps, i.e.
 	// different characters in the old and new chunk.
-	int const D_max = ceil(((double)M_ + N_)/2);
 	for (int D = 0; D <= D_max; ++D) {
 		// to be used in the status messages
 		D_ = D; 
@@ -651,6 +658,8 @@ int Compare::Impl::findMiddleSnake(DocRangePair const & rp,
 						return 2 * D - odd_offset_;
 					}
 				}
+				if (abort_)
+					return 0;
 			}
 		}
 	}
@@ -682,7 +691,9 @@ bool Compare::Impl::diff(Buffer const * new_buf, Buffer const * old_buf,
 	processSnake(snake);
 	
 	// Start the recursive algorithm
-	diff_i(rp);
+	DocRangePair rp_new(from, rp.to());
+	if (!rp_new.o.empty() || !rp_new.n.empty())
+		diff_i(rp_new);
 
 	for (pit_type p = 0; p < (pit_type)dest_pars_->size(); ++p) {
 		(*dest_pars_)[p].setBuffer(const_cast<Buffer &>(*dest_buf));
@@ -695,6 +706,9 @@ bool Compare::Impl::diff(Buffer const * new_buf, Buffer const * old_buf,
 
 void Compare::Impl::diff_i(DocRangePair const & rp)
 {
+	if (abort_)
+		return;
+
 	// The middle snake
 	DocPair middle_snake;