Only call callbacks that are not NULL. [Bug 1791052]

3 files changed, 42 insertions, 15 deletions

diff --git a/ChangeLog b/ChangeLog
index 3f895ff..681f4fd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2007-09-20  Donal K. Fellows  <dkf@users.sf.net>
+
+	* generic/tkTextDisp.c (LayoutDLine):  Only call callbacks that are
+	* tests/textDisp.test (textDisp-32.3): not NULL. [Bug 1791052]
+
 2007-09-20  Don Porter  <dgp@users.sourceforge.net>
 
 	*** 8.5b1 TAGGED FOR RELEASE ***
diff --git a/generic/tkTextDisp.c b/generic/tkTextDisp.c
index d5d827d..7e43bf1 100644
--- a/generic/tkTextDisp.c
+++ b/generic/tkTextDisp.c
@@ -12,7 +12,7 @@
  * See the file "license.terms" for information on usage and redistribution of
  * this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tkTextDisp.c,v 1.65 2007/09/07 00:34:54 dgp Exp $
+ * RCS: @(#) $Id: tkTextDisp.c,v 1.66 2007/09/20 22:59:40 dkf Exp $
  */
 
 #include "tkInt.h"
@@ -1551,6 +1551,7 @@ LayoutDLine(
 		 */
 
 		TkTextLine *linePtr = TkBTreeNextLine(NULL, curIndex.linePtr);
+
 		if (linePtr != NULL) {
 		    dlPtr->logicalLinesMerged++;
 		    curIndex.byteIndex = 0;
@@ -1609,11 +1610,15 @@ LayoutDLine(
 	    }
 	    FreeStyle(textPtr, chunkPtr->stylePtr);
 	    breakChunkPtr->nextPtr = chunkPtr->nextPtr;
-	    (*chunkPtr->undisplayProc)(textPtr, chunkPtr);
+	    if (chunkPtr->undisplayProc != NULL) {
+		(*chunkPtr->undisplayProc)(textPtr, chunkPtr);
+	    }
 	    ckfree((char *) chunkPtr);
 	}
 	if (breakByteOffset != breakChunkPtr->numBytes) {
-	    (*breakChunkPtr->undisplayProc)(textPtr, breakChunkPtr);
+	    if (breakChunkPtr->undisplayProc != NULL) {
+		(*breakChunkPtr->undisplayProc)(textPtr, breakChunkPtr);
+	    }
 	    segPtr = TkTextIndexToSeg(&breakIndex, &byteOffset);
 	    (*segPtr->typePtr->layoutProc)(textPtr, &breakIndex,
 		    segPtr, byteOffset, maxX, breakByteOffset, 0,
diff --git a/tests/textDisp.test b/tests/textDisp.test
index aa99a43..337b1ed 100644
--- a/tests/textDisp.test
+++ b/tests/textDisp.test
@@ -6,7 +6,7 @@
 # Copyright (c) 1998-1999 by Scriptics Corporation.
 # All rights reserved.
 #
-# RCS: @(#) $Id: textDisp.test,v 1.40 2006/03/23 16:26:12 dgp Exp $
+# RCS: @(#) $Id: textDisp.test,v 1.41 2007/09/20 22:59:41 dkf Exp $
 
 package require tcltest 2.1
 eval tcltest::configure $argv
@@ -3644,7 +3644,6 @@ test textDisp-32.0 {everything elided} {
     update ; update ; update ; update
     destroy .tt
 } {}
-
 test textDisp-32.1 {everything elided} {
     # Must not crash
     pack [text .tt]
@@ -3657,7 +3656,6 @@ test textDisp-32.1 {everything elided} {
     update ; update ; update ; update
     destroy .tt
 } {}
-
 test textDisp-32.2 {elide and tags} {
     pack [text .tt -height 30 -width 100 -bd 0 \
       -highlightthickness 0 -padx 0]
@@ -3675,7 +3673,6 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     # hide tag 1, remaining text should not be indented, since
     # the indented tag and character is hidden.
     .tt tag configure testtag1 -elide 1 ; update
@@ -3683,11 +3680,9 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     # reset
     .tt tag configure testtag1 -lmargin1 0
     .tt tag configure testtag1 -elide 0
-
     # indent left margin of tag 2 by 20 pixels
     # text should not be indented, since tag1 has lmargin1 of 0.
     .tt tag configure testtag2 -lmargin1 20 ; update
@@ -3695,7 +3690,6 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     # hide tag 1, remaining text should now be indented, but
     # the bbox of 1.0 should have zero width and zero indent,
     # since it is elided at that position.
@@ -3704,11 +3698,9 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     # reset
     .tt tag configure testtag2 -lmargin1 {}
     .tt tag configure testtag1 -elide 0
-
     # indent left margin of tag 3 by 20 pixels
     # text should be indented, since this tag takes
     # precedence over testtag1, and is applied to the
@@ -3718,7 +3710,6 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     # hide tag 1, remaining text should still be indented,
     # since it still has testtag3 on it.  Again the
     # bbox of 1.0 should have 0.
@@ -3727,18 +3718,44 @@ test textDisp-32.2 {elide and tags} {
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     .tt tag configure testtag3 -lmargin1 {} -elide 0
     .tt tag configure testtag1 -elide 1 -lmargin1 20
     #7
     lappend res [list [.tt index "1.0 + 0 displaychars"] \
       [lindex [.tt bbox 1.0] 0] \
       [lindex [.tt bbox "1.0 + 0 displaychars"] 0]]
-    
     destroy .tt
     set res
 } {{1.0 20 20} {1.29 0 0} {1.0 0 0} {1.29 0 20}\
   {1.0 20 20} {1.29 0 20} {1.0 20 20}}
+test textDisp-32.3 "NULL undisplayProc problems: #1791052" -setup {
+    set img [image create photo -data {
+	R0lGODlhEgASANUAAAAAAP/////iHP/mIPrWDPraEP/eGPfOAPbKAPbOBPrS
+	CP/aFPbGAPLCAPLGAN62ANauAMylAPbCAPW/APK+AN6uALKNAPK2APK5ANal
+	AOyzArGHBZp3B+6uAHFVBFVACO6qAOqqAOalAMGMAbF+Am1QBG5QBeuiAOad
+	AM6NAJ9vBW1MBFlACFQ9CVlBCuaZAOKVANyVAZlpBMyFAKZtBJVhBEAUEP//
+	/wAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACH5BAEAADcALAAAAAASABIAAAa+
+	wJtw+Ckah0iiZwNhODKk0icp/HAShEKBoEBgVFOkK0Iw2GyCs+BAGbGIlrIt
+	EJjXBYgL6X3zJMx1Z2d3EyEmNx9xaYGCdwgaNEUPBYt0do4XKUUOlAOCnmcD
+	CwcXMZsEAgOqq6oLBY+mHxUKBqysCwQSIDNFJAidtgKjFyeRfRQHB2ipAmZs
+	IDArVSTIyoI2bB0oxkIsIxcNyeIXICh7SR8yIhoXFxogJzE1YegrNCkoLzM0
+	K/RUiEY+tKASBAA7
+    }]
+    destroy .tt
+} -body {
+    text .tt
+    .tt tag configure emoticon -elide 1
+    .tt insert end X
+    .tt mark set MSGLEFT "end - 1 char"
+    .tt mark gravity MSGLEFT left
+    .tt insert end ":)" emoticon
+    .tt image create end -image $img
+    pack .tt
+    update; update; update
+} -cleanup {
+    image delete $img
+    destroy .tt
+}
 
 test textDisp-33.0 {one line longer than fits in the widget} {
     pack [text .tt -wrap char]