repl: fix Node crashes when press up arrow with multiline history

Author: illusory-dream

lib/internal/readline/interface.js

@@ -24,6 +24,7 @@ const {
   StringPrototypeCodePointAt,
   StringPrototypeEndsWith,
   StringPrototypeIncludes,
+  StringPrototypeLastIndexOf,
   StringPrototypeRepeat,
   StringPrototypeReplaceAll,
   StringPrototypeSlice,
@@ -1091,21 +1092,20 @@ class Interface extends InterfaceConstructor {
     this[kRefreshLine]();
   }
 
-  [kMultilineMove](direction, splitLines, { rows, cols }) {
-    const curr = splitLines[rows];
+  [kMultilineMove](direction, splitLines, { logicalRows, logicalCols }) {
+    const curr = splitLines[logicalRows];
     const down = direction === 1;
-    const adj = splitLines[rows + direction];
-    const promptLen = kMultilinePrompt.description.length;
+    const adj = splitLines[logicalRows + direction];
     let amountToMove;
-    // Clamp distance to end of current + prompt + next/prev line + newline
+    // Clamp distance to end of current + next/prev line + newline
     const clamp = down ?
-      curr.length - cols + promptLen + adj.length + 1 :
-      -cols + 1;
-    const shouldClamp = cols > adj.length + 1;
+      curr.length - logicalCols + adj.length + 1 :
+      -logicalCols - 1;
+    const shouldClamp = logicalCols > adj.length;
 
     if (shouldClamp) {
       if (this[kPreviousCursorCols] === -1) {
-        this[kPreviousCursorCols] = cols;
+        this[kPreviousCursorCols] = logicalCols;
       }
       amountToMove = clamp;
     } else {
@@ -1116,7 +1116,7 @@ class Interface extends InterfaceConstructor {
       }
       if (this[kPreviousCursorCols] !== -1) {
         if (this[kPreviousCursorCols] <= adj.length) {
-          amountToMove += this[kPreviousCursorCols] - cols;
+          amountToMove += this[kPreviousCursorCols] - logicalCols;
           this[kPreviousCursorCols] = -1;
         } else {
           amountToMove = clamp;
@@ -1128,10 +1128,10 @@ class Interface extends InterfaceConstructor {
   }
 
   [kMoveDownOrHistoryNext]() {
-    const cursorPos = this.getCursorPos();
+    const logicalCursorPos = this.getLogicalCursorPos();
     const splitLines = StringPrototypeSplit(this.line, '\n');
-    if (this[kIsMultiline] && cursorPos.rows < splitLines.length - 1) {
-      this[kMultilineMove](1, splitLines, cursorPos);
+    if (this[kIsMultiline] && logicalCursorPos.logicalRows < splitLines.length - 1) {
+      this[kMultilineMove](1, splitLines, logicalCursorPos);
       return;
     }
     this[kPreviousCursorCols] = -1;
@@ -1155,10 +1155,10 @@ class Interface extends InterfaceConstructor {
   }
 
   [kMoveUpOrHistoryPrev]() {
-    const cursorPos = this.getCursorPos();
-    if (this[kIsMultiline] && cursorPos.rows > 0) {
+    const logicalCursorPos = this.getLogicalCursorPos();
+    if (this[kIsMultiline] && logicalCursorPos.logicalRows > 0) {
       const splitLines = StringPrototypeSplit(this.line, '\n');
-      this[kMultilineMove](-1, splitLines, cursorPos);
+      this[kMultilineMove](-1, splitLines, logicalCursorPos);
       return;
     }
     this[kPreviousCursorCols] = -1;
@@ -1226,6 +1226,22 @@ class Interface extends InterfaceConstructor {
     return this[kGetDisplayPos](strBeforeCursor);
   }
 
+  /**
+   * Returns the logical position of the cursor within the input string
+   * excluding prompt and terminal formatting.
+   * @returns {{
+   *   logicalCols: number;
+   *   logicalRows: number;
+   *   }}
+   */
+  getLogicalCursorPos() {
+    const logicalCols = this.cursor - (StringPrototypeLastIndexOf(this.line, '\n', this.cursor - 1) + 1);
+    const strlineBeforeCursor = StringPrototypeSlice(this.line, 0, this.cursor);
+    const logicalRows = StringPrototypeSplit(strlineBeforeCursor, '\n').length - 1
+
+    return { logicalCols, logicalRows };
+  }
+
   // This function moves cursor dx places to the right
   // (-dx for left) and refreshes the line if it is needed.
   [kMoveCursor](dx) {