Backout the first three commits of the present branch, and implement a better fix. It's not the business of TkTextSetYView() to adjust the index it's receiving, it shall rather receive an index that is already within the -starline/-endline limits.

3 files changed, 51 insertions, 4 deletions

diff --git a/generic/tkText.c b/generic/tkText.c
index d1032e5..2938c28 100644
--- a/generic/tkText.c
+++ b/generic/tkText.c
@@ -3284,6 +3284,14 @@ DeleteIndexRange(
 
 	    if (tPtr == textPtr) {
 		if (viewUpdate) {
+		    /*
+		     * line cannot be before -startline of textPtr because
+		     * this line corresponds to an index which is necessarily
+		     * between "1.0" and "end" relative to textPtr.
+		     * Therefore no need to clamp line to the -start/-end
+		     * range.
+		     */
+
 		    TkTextMakeByteIndex(sharedTextPtr->tree, textPtr, line,
 			    byteIndex, &indexTmp);
 		    TkTextSetYView(tPtr, &indexTmp, 0);
@@ -3291,6 +3299,28 @@ DeleteIndexRange(
 	    } else {
 		TkTextMakeByteIndex(sharedTextPtr->tree, tPtr, line,
 			byteIndex, &indexTmp);
+		/*
+		 * line may be before -startline of tPtr and must be
+		 * clamped to -startline before providing it to
+		 * TkTextSetYView otherwise lines before -startline
+		 * would be displayed.
+		 * There is no need to worry about -endline however,
+		 * because the view will only be reset if the deletion
+		 * involves the TOP line of the screen
+		 */
+
+		if (tPtr->start != NULL) {
+		    int start;
+		    TkTextIndex indexStart;
+
+		    start = TkBTreeLinesTo(NULL, tPtr->start);
+		    TkTextMakeByteIndex(sharedTextPtr->tree, NULL, start,
+			    0, &indexStart);
+		    if (TkTextIndexCmp(&indexTmp, &indexStart) < 0) {
+			indexTmp = indexStart;
+			printf("ADJUSTED !!!!!!!!!!!!!!!!!!!!!!\n");
+		    }
+		}
 		TkTextSetYView(tPtr, &indexTmp, 0);
 	    }
 	}
diff --git a/generic/tkTextBTree.c b/generic/tkTextBTree.c
index 7832992..1b65cbc 100644
--- a/generic/tkTextBTree.c
+++ b/generic/tkTextBTree.c
@@ -1727,6 +1727,26 @@ TkBTreeFindPixelLine(
 	}
 	pixels -= linePtr->pixels[2 * pixelReference];
     }
+
+    /*
+     * Check for any start/end offset for this text widget.
+     */
+
+    if (textPtr->start != NULL) {
+	int lineBoundary = TkBTreeLinesTo(NULL, textPtr->start);
+
+	if (TkBTreeLinesTo(NULL, linePtr) < lineBoundary) {
+	    linePtr = TkBTreeFindLine(tree, NULL, lineBoundary);
+	}
+    }
+    if (textPtr->end != NULL) {
+	int lineBoundary = TkBTreeLinesTo(NULL, textPtr->end);
+
+	if (TkBTreeLinesTo(NULL, linePtr) > lineBoundary) {
+	    linePtr = TkBTreeFindLine(tree, NULL, lineBoundary);
+	}
+    }
+
     if (pixelOffset != NULL && linePtr != NULL) {
 	*pixelOffset = pixels;
     }
diff --git a/generic/tkTextDisp.c b/generic/tkTextDisp.c
index 814863b..a02544d 100644
--- a/generic/tkTextDisp.c
+++ b/generic/tkTextDisp.c
@@ -5328,7 +5328,6 @@ TkTextRelayoutWindow(
  *	The display will (eventually) be updated so that the position given by
  *	"indexPtr" is visible on the screen at the position determined by
  *	"pickPlace".
- *      indexPtr may be adjusted to the -startline/-endline range.
  *
  *----------------------------------------------------------------------
  */
@@ -5359,8 +5358,7 @@ TkTextSetYView(
 
     /*
      * If the specified position is the extra line at the end of the text,
-     * round it back to the last real line. Also, adjust to the -starline
-     * and -endline limits.
+     * round it back to the last real line.
      */
 
     lineIndex = TkBTreeLinesTo(textPtr, indexPtr->linePtr);
@@ -5368,7 +5366,6 @@ TkTextSetYView(
 	TkTextIndexBackChars(textPtr, indexPtr, 1, &rounded, COUNT_INDICES);
 	indexPtr = &rounded;
     }
-    TkTextIndexAdjustToStartEnd(textPtr, indexPtr, 0);
 
     if (pickPlace == TK_TEXT_NOPIXELADJUST) {
 	if (textPtr->topIndex.linePtr == indexPtr->linePtr