Merge pull request #16 from jstarks/more_scrolling_fixes

Fix DL, IL, SU, and SD
Azure · Aug 7, 2015 · 42a7d91 · 42a7d91
2 parents 326d07f + 0310580
commit 42a7d91
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Showing 2 changed files with 22 additions and 22 deletions.
diff --git a/winterm/scroll_helper.go b/winterm/scroll_helper.go
@@ -13,35 +13,39 @@ func (h *WindowsAnsiEventHandler) effectiveSr(window SMALL_RECT) scrollRegion {
 	return scrollRegion{top: top, bottom: bottom}
 }
 
-func (h *WindowsAnsiEventHandler) scrollPageUp() error {
-	return h.scrollPage(1)
-}
-
-func (h *WindowsAnsiEventHandler) scrollPageDown() error {
-	return h.scrollPage(-1)
-}
-
-func (h *WindowsAnsiEventHandler) scrollPage(param int) error {
+func (h *WindowsAnsiEventHandler) scrollUp(param int) error {
 	info, err := GetConsoleScreenBufferInfo(h.fd)
 	if err != nil {
 		return err
 	}
 
-	return h.scroll(param, scrollRegion{info.Window.Top, info.Window.Bottom}, info)
+	sr := h.effectiveSr(info.Window)
+	return h.scroll(param, sr, info)
 }
 
-func (h *WindowsAnsiEventHandler) scrollUp(param int) error {
+func (h *WindowsAnsiEventHandler) scrollDown(param int) error {
+	return h.scrollUp(-param)
+}
+
+func (h *WindowsAnsiEventHandler) deleteLines(param int) error {
 	info, err := GetConsoleScreenBufferInfo(h.fd)
 	if err != nil {
 		return err
 	}
 
+	start := info.CursorPosition.Y
 	sr := h.effectiveSr(info.Window)
-	return h.scroll(param, sr, info)
+	// Lines cannot be inserted or deleted outside the scrolling region.
+	if start >= sr.top && start <= sr.bottom {
+		sr.top = start
+		return h.scroll(param, sr, info)
+	} else {
+		return nil
+	}
 }
 
-func (h *WindowsAnsiEventHandler) scrollDown(param int) error {
-	return h.scrollUp(-param)
+func (h *WindowsAnsiEventHandler) insertLines(param int) error {
+	return h.deleteLines(-param)
 }
 
 // scroll scrolls the provided scroll region by param lines. The scroll region is in buffer coordinates.

diff --git a/winterm/win_event_handler.go b/winterm/win_event_handler.go
@@ -484,11 +484,7 @@ func (h *WindowsAnsiEventHandler) IL(param int) error {
 	}
 	logger.Infof("IL: [%v]", strconv.Itoa(param))
 	h.clearWrap()
-	if err := h.scrollDown(param); err != nil {
-		return err
-	}
-
-	return h.EL(2)
+	return h.insertLines(param)
 }
 
 func (h *WindowsAnsiEventHandler) DL(param int) error {
@@ -497,7 +493,7 @@ func (h *WindowsAnsiEventHandler) DL(param int) error {
 	}
 	logger.Infof("DL: [%v]", strconv.Itoa(param))
 	h.clearWrap()
-	return h.scrollUp(param)
+	return h.deleteLines(param)
 }
 
 func (h *WindowsAnsiEventHandler) SGR(params []int) error {
@@ -545,7 +541,7 @@ func (h *WindowsAnsiEventHandler) SU(param int) error {
 	}
 	logger.Infof("SU: [%v]", []string{strconv.Itoa(param)})
 	h.clearWrap()
-	return h.scrollPageUp()
+	return h.scrollUp(param)
 }
 
 func (h *WindowsAnsiEventHandler) SD(param int) error {
@@ -554,7 +550,7 @@ func (h *WindowsAnsiEventHandler) SD(param int) error {
 	}
 	logger.Infof("SD: [%v]", []string{strconv.Itoa(param)})
 	h.clearWrap()
-	return h.scrollPageDown()
+	return h.scrollDown(param)
 }
 
 func (h *WindowsAnsiEventHandler) DA(params []string) error {