single line wraps to whole display fix

3 files changed, 71 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 6abbb11..47cc504 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,7 +2,9 @@
 
 	* generic/tkTextDisp.c: 
 	* tests/textDisp.test: fixes to one more old Tk [Bug 422411]
-	this time concerning inconsistent tab interpretation.
+	this time concerning inconsistent tab interpretation.  Also
+	fixed an unreported new problem if a single logical line wraps
+	to fill more than the entire display.
 	
 2003-11-14  Joe English  <jenglish@users.sourceforge.net>
 	* doc/text.n: Fix markup errors.
diff --git a/generic/tkTextDisp.c b/generic/tkTextDisp.c
index 040c907..a3e311d 100644
--- a/generic/tkTextDisp.c
+++ b/generic/tkTextDisp.c
@@ -13,7 +13,7 @@
  * 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 1.31 2003/11/15 12:47:15 vincentdarley Exp $
+ * RCS: @(#) $Id: tkTextDisp.c,v 1.32 2003/11/15 16:57:57 vincentdarley Exp $
  */
 
 #include "tkPort.h"
@@ -5286,6 +5286,13 @@ GetXView(interp, textPtr, report)
  *
  *	How many pixels are there between the absolute top of the
  *	widget and the top of the given DLine.
+ *	
+ *	This is only ever called when dlPtr is the first display
+ *	line in the widget (by 'GetYView').  We have to be careful
+ *	if dlPtr's logical line wraps enough times to fill the
+ *	text widget's current view -- in this case we won't have
+ *	enough dlPtrs in the linked list to be able to subtract off
+ *	what we want.
  *
  * Results:
  *	The number of pixels.
@@ -5307,7 +5314,17 @@ GetPixelCount(textPtr, dlPtr)
      * Get the pixel count of one pixel beyond the 
      * botton of the given line.
      */
-    int count = TkBTreePixels(linePtr) + linePtr->pixelHeight;
+    int count = TkBTreePixels(linePtr);
+   
+    /* 
+     * For the common case where this dlPtr is also the start of 
+     * the logical line, we can return right away.
+     */
+    if (dlPtr->index.byteIndex == 0) {
+        return count;
+    }
+    
+    count += linePtr->pixelHeight;
 
     /* 
      * Now we have to subtract off the distance between the top of this
@@ -5315,8 +5332,32 @@ GetPixelCount(textPtr, dlPtr)
      */
     do {
 	count -= dlPtr->height;
-	dlPtr = dlPtr->nextPtr;
-    } while (dlPtr != NULL && (dlPtr->index.linePtr == linePtr));
+	if (dlPtr->nextPtr == NULL) {
+	    /* We've run out of lines */
+	    TkTextIndex index;
+	    DLine *dlPrev = NULL;
+	    while (1) {
+		TkTextIndexForwBytes(&dlPtr->index, dlPtr->byteCount, &index);
+		if (index.linePtr != linePtr) {
+		    break;
+		}
+		if (dlPrev != NULL) {
+		    FreeDLines(textPtr, dlPrev, (DLine *) NULL, 
+			       DLINE_FREE_TEMP);
+		}
+		dlPtr = LayoutDLine(textPtr, &index);
+		dlPrev = dlPtr;
+		count -= dlPtr->height;
+	    }
+	    if (dlPrev != NULL) {
+		FreeDLines(textPtr, dlPrev, (DLine *) NULL, 
+			   DLINE_FREE_TEMP);
+	    }
+	    break;
+	} else {
+	    dlPtr = dlPtr->nextPtr;
+	}
+    } while (dlPtr->index.linePtr == linePtr);
     
     return count;
 }
@@ -5374,7 +5415,7 @@ GetYView(interp, textPtr, report)
 	last = 1.0;
     } else {
 	/* 
-	 * Get the pixel count for the first display visible pixel of the
+	 * Get the pixel count for the first visible pixel of the
 	 * first visible line.  If the first visible line is only
 	 * partially visible, then we use 'topPixelOffset' to get the
 	 * difference.
diff --git a/tests/textDisp.test b/tests/textDisp.test
index bb60912..4fad84b 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 1.19 2003/11/15 12:47:15 vincentdarley Exp $
+# RCS: @(#) $Id: textDisp.test,v 1.20 2003/11/15 16:57:57 vincentdarley Exp $
 
 package require tcltest 2.1
 eval tcltest::configure $argv
@@ -3492,6 +3492,27 @@ test textDisp-32.1 {everything elided} {
     destroy .tt
 } {}
 
+test textDisp-33.0 {one line longer than fits in the widget} {
+    pack [text .tt -wrap char]
+    .tt insert 1.0 [string repeat "hello there " 2500]
+    update ; update ; update
+    .tt see 1.0
+    lindex [.tt yview] 0
+} {0.0}
+
+test textDisp-33.1 {one line longer than fits in the widget} {
+    destroy .tt
+    pack [text .tt -wrap char]
+    .tt insert 1.0 [string repeat "hello there " 2500]
+    update ; update ; update
+    .tt yview "1.0 +1 displaylines"
+    if {[lindex [.tt yview] 0] > 0.1} {
+	set result "bad result"
+    } else {
+	set result "ok"
+    }
+} {ok}
+
 deleteWindows
 option clear