From fe707b41f0a8ff33d9cad215cadc21f4cc3cae0c Mon Sep 17 00:00:00 2001
From: Jason Poon <git@jasonpoon.ca>
Date: Fri, 1 Feb 2019 20:38:05 -0800
Subject: [PATCH] fix: ensure cursor is in bounds. closes #3441

---
 src/common/motion/range.ts |  4 ++++
 src/mode/modeHandler.ts    | 38 ++++++++++++++++++++++++--------------
 src/state/vimState.ts      | 11 +++++------
 3 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/src/common/motion/range.ts b/src/common/motion/range.ts
index adf239d4fa2..a5f60ff3244 100644
--- a/src/common/motion/range.ts
+++ b/src/common/motion/range.ts
@@ -20,6 +20,10 @@ export class Range {
     this._stop = stop;
   }
 
+  public isValid(textEditor: vscode.TextEditor) {
+    return this._start.isValid(textEditor) && this._stop.isValid(textEditor);
+  }
+
   /**
    * Create a range from a VSCode selection.
    */
diff --git a/src/mode/modeHandler.ts b/src/mode/modeHandler.ts
index c67520362bf..3a536fae41d 100644
--- a/src/mode/modeHandler.ts
+++ b/src/mode/modeHandler.ts
@@ -606,25 +606,35 @@ export class ModeHandler implements vscode.Disposable {
 
     // Ensure cursor is within bounds
     if (!vimState.editor.document.isClosed && vimState.editor === vscode.window.activeTextEditor) {
-      for (const { stop, i } of Range.IterateRanges(vimState.allCursors)) {
-        if (stop.line >= TextEditor.getLineCount()) {
-          vimState.allCursors[i] = vimState.allCursors[i].withNewStop(
-            vimState.cursorPosition.getDocumentEnd(vimState.editor)
-          );
+      const cursors = new Array<Range>();
+      for (let { range } of Range.IterateRanges(vimState.allCursors)) {
+        // adjust start/stop
+        const documentEndPosition = vimState.cursorPosition.getDocumentEnd(vimState.editor);
+        const documentLineCount = TextEditor.getLineCount(vimState.editor);
+        if (range.start.line >= documentLineCount) {
+          range = range.withNewStart(documentEndPosition);
+        }
+        if (range.stop.line >= documentLineCount) {
+          range = range.withNewStop(documentEndPosition);
         }
 
-        const currentLineLength = TextEditor.getLineAt(stop).text.length;
+        // adjust column
+        if (vimState.currentMode === ModeName.Normal) {
+          const currentLineLength = TextEditor.getLineAt(range.stop).text.length;
+          if (currentLineLength > 0) {
+            const lineEndPosition = range.start.getLineEnd().getLeftThroughLineBreaks(true);
+            if (range.start.character >= currentLineLength) {
+              range = range.withNewStart(lineEndPosition);
+            }
 
-        if (
-          vimState.currentMode === ModeName.Normal &&
-          stop.character >= currentLineLength &&
-          currentLineLength > 0
-        ) {
-          vimState.allCursors[i] = vimState.allCursors[i].withNewStop(
-            stop.getLineEnd().getLeftThroughLineBreaks(true)
-          );
+            if (range.stop.character >= currentLineLength) {
+              range = range.withNewStop(lineEndPosition);
+            }
+          }
         }
+        cursors.push(range);
       }
+      vimState.allCursors = cursors;
     }
 
     // Update the current history step to have the latest cursor position
diff --git a/src/state/vimState.ts b/src/state/vimState.ts
index 09468361728..0cc3a8246fc 100644
--- a/src/state/vimState.ts
+++ b/src/state/vimState.ts
@@ -150,15 +150,14 @@ export class VimState implements vscode.Disposable {
     return this._allCursors;
   }
 
-  public set allCursors(value: Range[]) {
-    for (const cursor of value) {
-      if (!cursor.start.isValid(this.editor) || !cursor.stop.isValid(this.editor)) {
-        this.logger.debug('invalid value for set cursor position.');
+  public set allCursors(cursors: Range[]) {
+    for (const cursor of cursors) {
+      if (!cursor.isValid(this.editor)) {
+        this.logger.warn(`invalid cursor position. ${cursor.toString()}.`);
       }
     }
 
-    this._allCursors = value;
-
+    this._allCursors = cursors;
     this.isMultiCursor = this._allCursors.length > 1;
   }