From 48d2c3291937f1a2411daada450949cb2ccd884d Mon Sep 17 00:00:00 2001
From: Steve Lee <slee@microsoft.com>
Date: Tue, 29 May 2018 20:45:45 -0700
Subject: [PATCH 1/2] fix rendering where large content is pasted to console
 that is wider than console and also causes the screen buffer to scroll

---
 PSReadLine/Render.cs | 37 +++++++++++++++++++++++++++++++++++--
 1 file changed, 35 insertions(+), 2 deletions(-)

diff --git a/PSReadLine/Render.cs b/PSReadLine/Render.cs
index 791c2046..6efb69a4 100644
--- a/PSReadLine/Render.cs
+++ b/PSReadLine/Render.cs
@@ -427,15 +427,42 @@ int PhysicalLineCount(int columns, bool isFirstLogicalLine, out int lenLastPhysi
             var logicalLine = 0;
             var physicalLine = 0;
             var lenPrevLastLine = 0;
+            var suppressTopLineIfScrolled = true;
 
             for (; logicalLine < renderLines.Length; logicalLine++)
             {
                 if (logicalLine != 0) _console.Write("\n");
 
                 var lineData = renderLines[logicalLine];
-                _console.Write(lineData.line);
+                var physicalLineCount = PhysicalLineCount(lineData.columns, logicalLine == 0, out var lenLastLine);
 
-                physicalLine += PhysicalLineCount(lineData.columns, logicalLine == 0, out var lenLastLine);
+                // If the initial position was scrolled off the screen, only output for lines still
+                // in the screen buffer
+                if (_initialY + physicalLine >= 0)
+                {
+                    // First time redrawing from the top
+                    if (_initialY < 0 && suppressTopLineIfScrolled)
+                    {
+                        suppressTopLineIfScrolled = false;
+                        // Handle case where top of screen buffer is a partial line
+                        if (_console.CursorTop != 0 && _initialY + physicalLine != physicalLineCount)
+                        {
+                            var linesToSkip = _initialY + physicalLine;
+                            PlaceCursor(0, linesToSkip);
+                        }
+                    }
+                    _console.Write(lineData.line);
+                }
+
+                physicalLine += physicalLineCount;
+
+                // On non-Windows, if the last line fills the width exactly, it doesn't automatically scroll, so we
+                // need to decrement the count to make sure the y location is correct next time
+                if (_console.CursorTop == _console.BufferHeight - 1 && lineData.columns % _console.BufferWidth == 0)
+                {
+                    physicalLine--;
+                    previousPhysicalLine--;
+                }
 
                 // Find the previous logical line (if any) that would have rendered
                 // the current physical line because we may need to clear it.
@@ -671,6 +698,12 @@ private void PlaceCursor(int x, int y)
                 _initialY -= scrollCount;
                 y -= scrollCount;
             }
+
+            // y can be less than the screen buffer when a more text than the height of the buffer is pasted at once
+            if (y < 0)
+            {
+                y = 0;
+            }
             _console.SetCursorPosition(x, y);
         }
 

From 4aebcddc21defa96aaff532b10a0a7aad7f3a8e9 Mon Sep 17 00:00:00 2001
From: Steve Lee <slee@microsoft.com>
Date: Wed, 31 Oct 2018 13:55:30 -0700
Subject: [PATCH 2/2] address feedback

---
 PSReadLine/Render.cs |  7 +++++--
 test/KillYankTest.cs | 18 ++++++++++++++++++
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/PSReadLine/Render.cs b/PSReadLine/Render.cs
index 6efb69a4..ac487338 100644
--- a/PSReadLine/Render.cs
+++ b/PSReadLine/Render.cs
@@ -50,6 +50,9 @@ class RenderData
             lines = new[] { new RenderedLineData{ columns = 0, line = ""}}
         };
         private int _initialX;
+
+        // This represents the initial Y position of the cursor.  If this position has scrolled off screen, this value will be negative indicating
+        // the number of lines off screen.
         private int _initialY;
         private ConsoleColor _initialForeground;
         private ConsoleColor _initialBackground;
@@ -436,8 +439,8 @@ int PhysicalLineCount(int columns, bool isFirstLogicalLine, out int lenLastPhysi
                 var lineData = renderLines[logicalLine];
                 var physicalLineCount = PhysicalLineCount(lineData.columns, logicalLine == 0, out var lenLastLine);
 
-                // If the initial position was scrolled off the screen, only output for lines still
-                // in the screen buffer
+                // If the initial position was scrolled off the screen, _initialY will be negative.
+                // Only output for lines still in the screen buffer.
                 if (_initialY + physicalLine >= 0)
                 {
                     // First time redrawing from the top
diff --git a/test/KillYankTest.cs b/test/KillYankTest.cs
index 548c4d42..d64a6472 100644
--- a/test/KillYankTest.cs
+++ b/test/KillYankTest.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text;
 using System.Windows;
 using Microsoft.PowerShell;
 using Xunit;
@@ -313,6 +314,23 @@ public void Paste()
                 "echo foobar", _.CtrlShiftLeftArrow, _.CtrlV));
         }
 
+        [Fact]
+        public void PasteLarge()
+        {
+            TestSetup(KeyMode.Cmd);
+
+            StringBuilder text = new StringBuilder();
+            text.Append("@{");
+            for (int i = 0; i < _console.BufferHeight + 10; i++)
+            {
+                text.Append(string.Format("prop{0}={0}", i));
+            }
+            text.Append("}");
+
+            Clipboard.SetText(text.ToString());
+            Test(text.ToString(), Keys(_.CtrlV));
+        }
+
         [Fact]
         public void Cut()
         {