Merge pull request #843 from Tyriar/842_resize_buffers_bug

Resize both buffers on resize, clean up alt buffer state

src/Buffer.test.ts

@@ -5,17 +5,20 @@ import { assert } from 'chai';
 import { ITerminal } from './Interfaces';
 import { Buffer } from './Buffer';
 import { CircularList } from './utils/CircularList';
+import { MockTerminal } from './utils/TestUtils';
+
+const INIT_COLS = 80;
+const INIT_ROWS = 24;
 
 describe('Buffer', () => {
   let terminal: ITerminal;
   let buffer: Buffer;
 
   beforeEach(() => {
-    terminal = <any>{
-      cols: 80,
-      rows: 24,
-      scrollback: 1000
-    };
+    terminal = new MockTerminal();
+    terminal.cols = INIT_COLS;
+    terminal.rows = INIT_ROWS;
+    terminal.scrollback = 1000;
     buffer = new Buffer(terminal);
   });
 
@@ -28,4 +31,117 @@ describe('Buffer', () => {
       assert.equal(buffer.scrollBottom, terminal.rows - 1);
     });
   });
+
+  describe('fillViewportRows', () => {
+    it('should fill the buffer with blank lines based on the size of the viewport', () => {
+      const blankLineChar = terminal.blankLine()[0];
+      buffer.fillViewportRows();
+      assert.equal(buffer.lines.length, INIT_ROWS);
+      for (let y = 0; y < INIT_ROWS; y++) {
+        assert.equal(buffer.lines.get(y).length, INIT_COLS);
+        for (let x = 0; x < INIT_COLS; x++) {
+          assert.deepEqual(buffer.lines.get(y)[x], blankLineChar);
+        }
+      }
+    });
+  });
+
+  describe('resize', () => {
+    describe('column size is reduced', () => {
+      it('should not trim the data in the buffer', () => {
+        buffer.fillViewportRows();
+        buffer.resize(INIT_COLS / 2, INIT_ROWS);
+        assert.equal(buffer.lines.length, INIT_ROWS);
+        for (let i = 0; i < INIT_ROWS; i++) {
+          assert.equal(buffer.lines.get(i).length, INIT_COLS);
+        }
+      });
+    });
+
+    describe('column size is increased', () => {
+      it('should add pad columns', () => {
+        buffer.fillViewportRows();
+        buffer.resize(INIT_COLS + 10, INIT_ROWS);
+        assert.equal(buffer.lines.length, INIT_ROWS);
+        for (let i = 0; i < INIT_ROWS; i++) {
+          assert.equal(buffer.lines.get(i).length, INIT_COLS + 10);
+        }
+      });
+    });
+
+    describe('row size reduced', () => {
+      it('should trim blank lines from the end', () => {
+        buffer.fillViewportRows();
+        buffer.resize(INIT_COLS, INIT_ROWS - 10);
+        assert.equal(buffer.lines.length, INIT_ROWS - 10);
+      });
+
+      it('should move the viewport down when it\'s at the end', () => {
+        buffer.fillViewportRows();
+        // Set cursor y to have 5 blank lines below it
+        buffer.y = INIT_ROWS - 5 - 1;
+        buffer.resize(INIT_COLS, INIT_ROWS - 10);
+        // Trim 5 rows
+        assert.equal(buffer.lines.length, INIT_ROWS - 5);
+        // Shift the viewport down 5 rows
+        assert.equal(buffer.ydisp, 5);
+        assert.equal(buffer.ybase, 5);
+      });
+    });
+
+    describe('row size increased', () => {
+      describe('empty buffer', () => {
+        it('should add blank lines to end', () => {
+          buffer.fillViewportRows();
+          assert.equal(buffer.ydisp, 0);
+          buffer.resize(INIT_COLS, INIT_ROWS + 10);
+          assert.equal(buffer.ydisp, 0);
+          assert.equal(buffer.lines.length, INIT_ROWS + 10);
+        });
+      });
+
+      describe('filled buffer', () => {
+        it('should show more of the buffer above', () => {
+          buffer.fillViewportRows();
+          // Create 10 extra blank lines
+          for (let i = 0; i < 10; i++) {
+            buffer.lines.push(terminal.blankLine());
+          }
+          // Set cursor to the bottom of the buffer
+          buffer.y = INIT_ROWS - 1;
+          // Scroll down 10 lines
+          buffer.ybase = 10;
+          buffer.ydisp = 10;
+          assert.equal(buffer.lines.length, INIT_ROWS + 10);
+          buffer.resize(INIT_COLS, INIT_ROWS + 5);
+          // Should be should 5 more lines
+          assert.equal(buffer.ydisp, 5);
+          assert.equal(buffer.ybase, 5);
+          // Should not trim the buffer
+          assert.equal(buffer.lines.length, INIT_ROWS + 10);
+        });
+
+        it('should show more of the buffer below when the viewport is at the top of the buffer', () => {
+          buffer.fillViewportRows();
+          // Create 10 extra blank lines
+          for (let i = 0; i < 10; i++) {
+            buffer.lines.push(terminal.blankLine());
+          }
+          // Set cursor to the bottom of the buffer
+          buffer.y = INIT_ROWS - 1;
+          // Scroll down 10 lines
+          buffer.ybase = 10;
+          buffer.ydisp = 0;
+          assert.equal(buffer.lines.length, INIT_ROWS + 10);
+          buffer.resize(INIT_COLS, INIT_ROWS + 5);
+          // The viewport should remain at the top
+          assert.equal(buffer.ydisp, 0);
+          // The buffer ybase should move up 5 lines
+          assert.equal(buffer.ybase, 5);
+          // Should not trim the buffer
+          assert.equal(buffer.lines.length, INIT_ROWS + 10);
+        });
+      });
+    });
+  });
 });

src/Buffer.ts

@@ -2,7 +2,7 @@
  * @license MIT
  */
 
-import { ITerminal } from './Interfaces';
+import { ITerminal, IBuffer } from './Interfaces';
 import { CircularList } from './utils/CircularList';
 
 /**
@@ -12,31 +12,137 @@ import { CircularList } from './utils/CircularList';
  *   - cursor position
  *   - scroll position
  */
-export class Buffer {
-  public lines: CircularList<[number, string, number][]>;
+export class Buffer implements IBuffer {
+  private _lines: CircularList<[number, string, number][]>;
 
+  public ydisp: number;
+  public ybase: number;
+  public y: number;
+  public x: number;
+  public scrollBottom: number;
+  public scrollTop: number;
+  public tabs: any;
   public savedY: number;
   public savedX: number;
 
   /**
    * Create a new Buffer.
-   * @param {Terminal} terminal - The terminal the Buffer will belong to
+   * @param {Terminal} _terminal - The terminal the Buffer will belong to
    * @param {number} ydisp - The scroll position of the Buffer in the viewport
    * @param {number} ybase - The scroll position of the y cursor (ybase + y = the y position within the Buffer)
    * @param {number} y - The cursor's y position after ybase
    * @param {number} x - The cursor's x position after ybase
    */
   constructor(
-    private terminal: ITerminal,
-    public ydisp: number = 0,
-    public ybase: number = 0,
-    public y: number = 0,
-    public x: number = 0,
-    public scrollBottom: number = 0,
-    public scrollTop: number = 0,
-    public tabs: any = {},
+    private _terminal: ITerminal
   ) {
-    this.lines = new CircularList<[number, string, number][]>(this.terminal.scrollback);
-    this.scrollBottom = this.terminal.rows - 1;
+    this.clear();
+  }
+
+  public get lines(): CircularList<[number, string, number][]> {
+    return this._lines;
+  }
+
+  /**
+   * Fills the buffer's viewport with blank lines.
+   */
+  public fillViewportRows(): void {
+    if (this._lines.length === 0) {
+      let i = this._terminal.rows;
+      while (i--) {
+        this.lines.push(this._terminal.blankLine());
+      }
+    }
+  }
+
+  /**
+   * Clears the buffer to it's initial state, discarding all previous data.
+   */
+  public clear(): void {
+    this.ydisp = 0;
+    this.ybase = 0;
+    this.y = 0;
+    this.x = 0;
+    this.scrollBottom = 0;
+    this.scrollTop = 0;
+    this.tabs = {};
+    this._lines = new CircularList<[number, string, number][]>(this._terminal.scrollback);
+    this.scrollBottom = this._terminal.rows - 1;
+  }
+
+  /**
+   * Resizes the buffer, adjusting its data accordingly.
+   * @param newCols The new number of columns.
+   * @param newRows The new number of rows.
+   */
+  public resize(newCols: number, newRows: number): void {
+    // Don't resize the buffer if it's empty and hasn't been used yet.
+    if (this._lines.length === 0) {
+      return;
+    }
+
+    // Deal with columns increasing (we don't do anything when columns reduce)
+    if (this._terminal.cols < newCols) {
+      const ch: [number, string, number] = [this._terminal.defAttr, ' ', 1]; // does xterm use the default attr?
+      for (let i = 0; i < this._lines.length; i++) {
+        if (this._lines.get(i) === undefined) {
+          this._lines.set(i, this._terminal.blankLine());
+        }
+        while (this._lines.get(i).length < newCols) {
+          this._lines.get(i).push(ch);
+        }
+      }
+    }
+
+    // Resize rows in both directions as needed
+    let addToY = 0;
+    if (this._terminal.rows < newRows) {
+      for (let y = this._terminal.rows; y < newRows; y++) {
+        if (this._lines.length < newRows + this.ybase) {
+          if (this.ybase > 0 && this._lines.length <= this.ybase + this.y + addToY + 1) {
+            // There is room above the buffer and there are no empty elements below the line,
+            // scroll up
+            this.ybase--;
+            addToY++;
+            if (this.ydisp > 0) {
+              // Viewport is at the top of the buffer, must increase downwards
+              this.ydisp--;
+            }
+          } else {
+            // Add a blank line if there is no buffer left at the top to scroll to, or if there
+            // are blank lines after the cursor
+            this._lines.push(this._terminal.blankLine());
+          }
+        }
+      }
+    } else { // (this._terminal.rows >= newRows)
+      for (let y = this._terminal.rows; y > newRows; y--) {
+        if (this._lines.length > newRows + this.ybase) {
+          if (this._lines.length > this.ybase + this.y + 1) {
+            // The line is a blank line below the cursor, remove it
+            this._lines.pop();
+          } else {
+            // The line is the cursor, scroll down
+            this.ybase++;
+            this.ydisp++;
+          }
+        }
+      }
+    }
+
+    // Make sure that the cursor stays on screen
+    if (this.y >= newRows) {
+      this.y = newRows - 1;
+    }
+    if (addToY) {
+      this.y += addToY;
+    }
+
+    if (this.x >= newCols) {
+      this.x = newCols - 1;
+    }
+
+    this.scrollTop = 0;
+    this.scrollBottom = newRows - 1;
   }
 }

src/BufferSet.test.ts

@@ -5,17 +5,17 @@ import { assert } from 'chai';
 import { ITerminal } from './Interfaces';
 import { BufferSet } from './BufferSet';
 import { Buffer } from './Buffer';
+import { MockTerminal } from './utils/TestUtils';
 
 describe('BufferSet', () => {
   let terminal: ITerminal;
   let bufferSet: BufferSet;
 
   beforeEach(() => {
-    terminal = <any>{
-      cols: 80,
-      rows: 24,
-      scrollback: 1000
-    };
+    terminal = new MockTerminal();
+    terminal.cols = 80;
+    terminal.rows = 24;
+    terminal.scrollback = 1000;
     bufferSet = new BufferSet(terminal);
   });
 

src/BufferSet.ts

@@ -22,6 +22,7 @@ export class BufferSet extends EventEmitter implements IBufferSet {
   constructor(private _terminal: ITerminal) {
     super();
     this._normal = new Buffer(this._terminal);
+    this._normal.fillViewportRows();
     this._alt = new Buffer(this._terminal);
     this._activeBuffer = this._normal;
   }
@@ -54,6 +55,11 @@ export class BufferSet extends EventEmitter implements IBufferSet {
    * Sets the normal Buffer of the BufferSet as its currently active Buffer
    */
   public activateNormalBuffer(): void {
+    // The alt buffer should always be cleared when we switch to the normal
+    // buffer. This frees up memory since the alt buffer should always be new
+    // when activated.
+    this._alt.clear();
+
     this._activeBuffer = this._normal;
     this.emit('activate', this._normal);
   }
@@ -62,7 +68,21 @@ export class BufferSet extends EventEmitter implements IBufferSet {
    * Sets the alt Buffer of the BufferSet as its currently active Buffer
    */
   public activateAltBuffer(): void {
+    // Since the alt buffer is always cleared when the normal buffer is
+    // activated, we want to fill it when switching to it.
+    this._alt.fillViewportRows();
+
     this._activeBuffer = this._alt;
     this.emit('activate', this._alt);
   }
+
+  /**
+   * Resizes both normal and alt buffers, adjusting their data accordingly.
+   * @param newCols The new number of columns.
+   * @param newRows The new number of rows.
+   */
+  public resize(newCols: number, newRows: number): void {
+    this._normal.resize(newCols, newRows);
+    this._alt.resize(newCols, newRows);
+  }
 }

src/InputHandler.ts

@@ -954,7 +954,6 @@ export class InputHandler implements IInputHandler {
         case 47: // alt screen buffer
         case 1047: // alt screen buffer
           this._terminal.buffers.activateAltBuffer();
-          this._terminal.reset();
           this._terminal.viewport.syncScrollArea();
           this._terminal.showCursor();
           break;

src/Interfaces.ts

@@ -48,6 +48,7 @@ export interface ITerminal {
   emit(event: string, data: any);
   reset(): void;
   showCursor(): void;
+  blankLine(cur?: boolean, isWrapped?: boolean);
 }
 
 export interface IBuffer {
@@ -92,8 +93,8 @@ export interface ILinkifier {
 export interface ICircularList<T> extends IEventEmitter {
   length: number;
   maxLength: number;
+  forEach: (callbackfn: (value: T, index: number) => void) => void;
 
-  forEach(callbackfn: (value: T, index: number, array: T[]) => void): void;
   get(index: number): T;
   set(index: number, value: T): void;
   push(value: T): void;

src/SelectionManager.test.ts

@@ -9,6 +9,7 @@ import { CircularList } from './utils/CircularList';
 import { SelectionManager } from './SelectionManager';
 import { SelectionModel } from './SelectionModel';
 import { BufferSet } from './BufferSet';
+import { MockTerminal } from './utils/TestUtils';
 
 class TestSelectionManager extends SelectionManager {
   constructor(
@@ -46,7 +47,9 @@ describe('SelectionManager', () => {
     window = dom.window;
     document = window.document;
     rowContainer = document.createElement('div');
-    terminal = <any>{ cols: 80, rows: 2 };
+    terminal = new MockTerminal();
+    terminal.cols = 80;
+    terminal.rows = 2;
     terminal.scrollback = 100;
     terminal.buffers = new BufferSet(terminal);
     terminal.buffer = terminal.buffers.active;
@@ -64,7 +67,7 @@ describe('SelectionManager', () => {
 
   describe('_selectWordAt', () => {
     it('should expand selection for normal width chars', () => {
-      bufferLines.push(stringToRow('foo bar'));
+      bufferLines.set(0, stringToRow('foo bar'));
       selectionManager.selectWordAt([0, 0]);
       assert.equal(selectionManager.selectionText, 'foo');
       selectionManager.selectWordAt([1, 0]);
@@ -81,7 +84,7 @@ describe('SelectionManager', () => {
       assert.equal(selectionManager.selectionText, 'bar');
     });
     it('should expand selection for whitespace', () => {
-      bufferLines.push(stringToRow('a   b'));
+      bufferLines.set(0, stringToRow('a   b'));
       selectionManager.selectWordAt([0, 0]);
       assert.equal(selectionManager.selectionText, 'a');
       selectionManager.selectWordAt([1, 0]);
@@ -95,7 +98,7 @@ describe('SelectionManager', () => {
     });
     it('should expand selection for wide characters', () => {
       // Wide characters use a special format
-      bufferLines.push([
+      bufferLines.set(0, [
         [null, '中', 2],
         [null, '', 0],
         [null, '文', 2],
@@ -147,7 +150,7 @@ describe('SelectionManager', () => {
       assert.equal(selectionManager.selectionText, 'foo');
     });
     it('should select up to non-path characters that are commonly adjacent to paths', () => {
-      bufferLines.push(stringToRow('(cd)[ef]{gh}\'ij"'));
+      bufferLines.set(0, stringToRow('(cd)[ef]{gh}\'ij"'));
       selectionManager.selectWordAt([0, 0]);
       assert.equal(selectionManager.selectionText, '(cd');
       selectionManager.selectWordAt([1, 0]);
@@ -185,7 +188,7 @@ describe('SelectionManager', () => {
 
   describe('_selectLineAt', () => {
     it('should select the entire line', () => {
-      bufferLines.push(stringToRow('foo bar'));
+      bufferLines.set(0, stringToRow('foo bar'));
       selectionManager.selectLineAt(0);
       assert.equal(selectionManager.selectionText, 'foo bar', 'The selected text is correct');
       assert.deepEqual(selectionManager.model.finalSelectionStart, [0, 0]);
@@ -195,11 +198,12 @@ describe('SelectionManager', () => {
 
   describe('selectAll', () => {
     it('should select the entire buffer, beyond the viewport', () => {
-      bufferLines.push(stringToRow('1'));
-      bufferLines.push(stringToRow('2'));
-      bufferLines.push(stringToRow('3'));
-      bufferLines.push(stringToRow('4'));
-      bufferLines.push(stringToRow('5'));
+      bufferLines.length = 5;
+      bufferLines.set(0, stringToRow('1'));
+      bufferLines.set(1, stringToRow('2'));
+      bufferLines.set(2, stringToRow('3'));
+      bufferLines.set(3, stringToRow('4'));
+      bufferLines.set(4, stringToRow('5'));
       selectionManager.selectAll();
       terminal.buffer.ybase = bufferLines.length - terminal.rows;
       assert.equal(selectionManager.selectionText, '1\n2\n3\n4\n5');

src/SelectionModel.test.ts

@@ -5,6 +5,7 @@ import { assert } from 'chai';
 import { ITerminal } from './Interfaces';
 import { SelectionModel } from './SelectionModel';
 import {BufferSet} from './BufferSet';
+import { MockTerminal } from './utils/TestUtils';
 
 class TestSelectionModel extends SelectionModel {
   constructor(
@@ -22,7 +23,9 @@ describe('SelectionManager', () => {
   let model: TestSelectionModel;
 
   beforeEach(() => {
-    terminal = <any>{ cols: 80, rows: 2, ybase: 0 };
+    terminal = new MockTerminal();
+    terminal.cols = 80;
+    terminal.rows = 2;
     terminal.scrollback = 10;
     terminal.buffers = new BufferSet(terminal);
     terminal.buffer = terminal.buffers.active;

src/utils/CircularList.ts

@@ -5,8 +5,9 @@
  * @license MIT
  */
 import { EventEmitter } from '../EventEmitter';
+import { ICircularList } from '../Interfaces';
 
-export class CircularList<T> extends EventEmitter {
+export class CircularList<T> extends EventEmitter implements ICircularList<T> {
   private _array: T[];
   private _startIndex: number;
   private _length: number;

src/utils/TestUtils.ts

@@ -0,0 +1,53 @@
+import { ITerminal, IBuffer, IBufferSet, IBrowser, ICharMeasure, ISelectionManager } from '../Interfaces';
+
+export class MockTerminal implements ITerminal {
+  public element: HTMLElement;
+  public rowContainer: HTMLElement;
+  public selectionContainer: HTMLElement;
+  public selectionManager: ISelectionManager;
+  public charMeasure: ICharMeasure;
+  public textarea: HTMLTextAreaElement;
+  public rows: number;
+  public cols: number;
+  public browser: IBrowser;
+  public writeBuffer: string[];
+  public children: HTMLElement[];
+  public cursorHidden: boolean;
+  public cursorState: number;
+  public defAttr: number;
+  public scrollback: number;
+  public buffers: IBufferSet;
+  public buffer: IBuffer;
+
+  handler(data: string) {
+    throw new Error('Method not implemented.');
+  }
+  on(event: string, callback: () => void) {
+    throw new Error('Method not implemented.');
+  }
+  scrollDisp(disp: number, suppressScrollEvent: boolean) {
+    throw new Error('Method not implemented.');
+  }
+  cancel(ev: Event, force?: boolean) {
+    throw new Error('Method not implemented.');
+  }
+  log(text: string): void {
+    throw new Error('Method not implemented.');
+  }
+  emit(event: string, data: any) {
+    throw new Error('Method not implemented.');
+  }
+  reset(): void {
+    throw new Error('Method not implemented.');
+  }
+  showCursor(): void {
+    throw new Error('Method not implemented.');
+  }
+  blankLine(cur?: boolean, isWrapped?: boolean) {
+    const line = [];
+    for (let i = 0; i < this.cols; i++) {
+      line.push([0, ' ', 1]);
+    }
+    return line;
+  }
+}

src/xterm.js

@@ -227,11 +227,6 @@ function Terminal(options) {
     this._terminal.buffer = buffer;
   });
 
-  var i = this.rows;
-
-  while (i--) {
-    this.buffer.lines.push(this.blankLine());
-  }
   // Ensure the selection manager has the correct buffer
   if (this.selectionManager) {
     this.selectionManager.setBuffer(this.buffer.lines);
@@ -1930,86 +1925,21 @@ Terminal.prototype.resize = function(x, y) {
   if (x < 1) x = 1;
   if (y < 1) y = 1;
 
-  // resize cols
-  j = this.cols;
-  if (j < x) {
-    ch = [this.defAttr, ' ', 1]; // does xterm use the default attr?
-    i = this.buffer.lines.length;
-    while (i--) {
-      if (this.buffer.lines.get(i) === undefined) {
-        this.buffer.lines.set(i, this.blankLine());
-      }
-      while (this.buffer.lines.get(i).length < x) {
-        this.buffer.lines.get(i).push(ch);
-      }
-    }
+  this.buffers.resize(x, y);
+
+  // Adjust rows in the DOM to accurately reflect the new dimensions
+  while (this.children.length < y) {
+    this.insertRow();
+  }
+  while (this.children.length > y) {
+    el = this.children.shift();
+    if (!el) continue;
+    el.parentNode.removeChild(el);
   }
 
   this.cols = x;
-  this.setupStops(this.cols);
-
-  // resize rows
-  j = this.rows;
-  addToY = 0;
-  if (j < y) {
-    el = this.element;
-    while (j++ < y) {
-      // y is rows, not this.buffer.y
-      if (this.buffer.lines.length < y + this.buffer.ybase) {
-        if (this.buffer.ybase > 0 && this.buffer.lines.length <= this.buffer.ybase + this.buffer.y + addToY + 1) {
-          // There is room above the buffer and there are no empty elements below the line,
-          // scroll up
-          this.buffer.ybase--;
-          addToY++;
-          if (this.buffer.ydisp > 0) {
-            // Viewport is at the top of the buffer, must increase downwards
-            this.buffer.ydisp--;
-          }
-        } else {
-          // Add a blank line if there is no buffer left at the top to scroll to, or if there
-          // are blank lines after the cursor
-          this.buffer.lines.push(this.blankLine());
-        }
-      }
-      if (this.children.length < y) {
-        this.insertRow();
-      }
-    }
-  } else { // (j > y)
-    while (j-- > y) {
-      if (this.buffer.lines.length > y + this.buffer.ybase) {
-        if (this.buffer.lines.length > this.buffer.ybase + this.buffer.y + 1) {
-          // The line is a blank line below the cursor, remove it
-          this.buffer.lines.pop();
-        } else {
-          // The line is the cursor, scroll down
-          this.buffer.ybase++;
-          this.buffer.ydisp++;
-        }
-      }
-      if (this.children.length > y) {
-        el = this.children.shift();
-        if (!el) continue;
-        el.parentNode.removeChild(el);
-      }
-    }
-  }
   this.rows = y;
-
-  // Make sure that the cursor stays on screen
-  if (this.buffer.y >= y) {
-    this.buffer.y = y - 1;
-  }
-  if (addToY) {
-    this.buffer.y += addToY;
-  }
-
-  if (this.buffer.x >= x) {
-    this.buffer.x = x - 1;
-  }
-
-  this.buffer.scrollTop = 0;
-  this.buffer.scrollBottom = y - 1;
+  this.setupStops(this.cols);
 
   this.charMeasure.measure();
 
@@ -2293,12 +2223,10 @@ Terminal.prototype.reset = function() {
   var customKeyEventHandler = this.customKeyEventHandler;
   var cursorBlinkInterval = this.cursorBlinkInterval;
   var inputHandler = this.inputHandler;
-  var buffers = this.buffers;
   Terminal.call(this, this.options);
   this.customKeyEventHandler = customKeyEventHandler;
   this.cursorBlinkInterval = cursorBlinkInterval;
   this.inputHandler = inputHandler;
-  this.buffers = buffers;
   this.refresh(0, this.rows - 1);
   this.viewport.syncScrollArea();
 };