vi-mode: Make 'D' and 'd$' delete to the end of the current logical line (#1695)

Author: springcomp

PSReadLine/Position.cs

@@ -93,6 +93,16 @@ private static int GetEndOfLogicalLinePos(int current)
             return newCurrent;
         }
 
+        /// <summary>
+        /// Returns the position of the end of the logical line
+        /// for the 0-based specified line number.
+        /// </summary>
+        private static int GetEndOfNthLogicalLinePos(int lineIndex)
+        {
+            return GetEndOfLogicalLinePos(
+                GetBeginningOfNthLinePos(lineIndex));
+        }
+
         /// <summary>
         /// Returns the position of the first non whitespace character in
         /// the current logical line as specified by the "current" position.

PSReadLine/ReadLine.vi.cs

@@ -220,16 +220,43 @@ public static void DeleteToEnd(ConsoleKeyInfo? key = null, object arg = null)
                 return;
             }
 
-            _clipboard.Record(_singleton._buffer, _singleton._current, _singleton._buffer.Length - _singleton._current);
-            _singleton.SaveEditItem(EditItemDelete.Create(
-                _clipboard,
-                _singleton._current,
-                DeleteToEnd,
-                arg
-                ));
-            _singleton._buffer.Remove(_singleton._current, _singleton._buffer.Length - _singleton._current);
-            _singleton._current = Math.Max(0, _singleton._buffer.Length - 1);
-            _singleton.Render();
+            var lineCount = _singleton.GetLogicalLineCount();
+            var lineIndex = _singleton.GetLogicalLineNumber() - 1;
+
+            if (TryGetArgAsInt(arg, out var requestedLineCount, 1))
+            {
+                var targetLineIndex = lineIndex + requestedLineCount - 1;
+                if (targetLineIndex >= lineCount)
+                {
+                    targetLineIndex = lineCount - 1;
+                }
+
+                var startPosition = _singleton._current;
+                var endPosition = GetEndOfNthLogicalLinePos(targetLineIndex);
+
+                var length = endPosition - startPosition + 1;
+                if (length > 0)
+                {
+                    _clipboard.Record(_singleton._buffer, startPosition, length);
+                    _singleton.SaveEditItem(EditItemDelete.Create(
+                        _clipboard,
+                        _singleton._current,
+                        DeleteToEnd,
+                        arg));
+
+                    _singleton._buffer.Remove(_singleton._current, length);
+
+                    // the cursor will go back one character, unless at the beginning of the line
+                    var endOfLineCursorPos = GetEndOfLogicalLinePos(_singleton._current) - 1;
+                    var beginningOfLinePos = GetBeginningOfLinePos(_singleton._current);
+
+                    _singleton._current = Math.Max(
+                        beginningOfLinePos,
+                        Math.Min(_singleton._current, endOfLineCursorPos));
+
+                    _singleton.Render();
+                }
+            }
         }
 
         /// <summary>

test/BasicEditingTest.VI.cs

@@ -489,6 +489,26 @@ public void ViDeleteToEndOfBuffer()
                 ));
         }
 
+        [SkippableFact]
+        public void ViDeleteToEnd()
+        {
+            TestSetup(KeyMode.Vi);
+
+            int continuationPrefixLength = PSConsoleReadLineOptions.DefaultContinuationPrompt.Length;
+
+            Test("\"\no\nthree\n\"", Keys(
+                _.DQuote, _.Enter,
+                "one", _.Enter,
+                "two", _.Enter,
+                "three", _.Enter,
+                _.DQuote, _.Escape,
+                "kkkl", // go to the 'ne' portion of "one"
+                // delete to the end of the next line
+                "2d$",
+                CheckThat(() => AssertCursorLeftIs(continuationPrefixLength + 0))
+                ));
+        }
+
         [SkippableFact]
         public void ViGlobDelete()
         {