fix DECSTBM with IND

fixtures/escape_sequence_files/t0071-DECSTBM_IND.in

@@ -1,3 +1,3 @@
 1D2D3D4D5D6D7D8D9ABCDEFaDbDcDdDeDfDgDhDiDjDkDlDmDnDoDpDqDrDsDtDuvwxyz
-
+
 The end.

fixtures/escape_sequence_files/t0071-DECSTBM_IND.text

@@ -1,4 +1,3 @@
- 2
      6
       7
        8
@@ -21,5 +20,6 @@ DEF
                  o
                   p
                    q
-The end.            rstu                                                     vwx
+yz                  rstu                                                     vwx
+The end.
 

src/InputHandler.ts

@@ -2048,10 +2048,13 @@ export class InputHandler extends Disposable implements IInputHandler {
    */
   public index(): void {
     this._restrictCursor();
+    const buffer = this._bufferService.buffer;
     this._bufferService.buffer.y++;
-    if (this._bufferService.buffer.y > this._bufferService.buffer.scrollBottom) {
-      this._bufferService.buffer.y--;
+    if (buffer.y === buffer.scrollBottom + 1) {
+      buffer.y--;
       this._terminal.scroll();
+    } else if (buffer.y >= this._bufferService.rows) {
+      buffer.y = this._bufferService.rows - 1;
     }
     this._restrictCursor();
   }

src/Terminal2.test.ts

@@ -17,8 +17,6 @@ const ROWS = 25;
 
 const TESTFILES = glob.sync('**/escape_sequence_files/*.in', { cwd: path.join(__dirname, '..')});
 const SKIP_FILES = [
-  // 't0070-DECSTBM_LF.in',      // lineFeed not working correctly
-  't0071-DECSTBM_IND.in',
   't0072-DECSTBM_NEL.in',
   't0075-DECSTBM_CUU_CUD.in',
   't0076-DECSTBM_IL_DL.in',   // not working due to lineFeed