Merge remote-tracking branch 'origin/master' into pr/gou4shi1/1788

2026-08-05 13:43:48 -07:00 · 2018-12-09 10:02:55 -08:00
parent 6b9fb48898 b5f1c3384a
commit 48629e7eb2
62 changed files with 919 additions and 454 deletions
@@ -30,7 +30,8 @@ opening an issue, read these pointers.

 ## Contributing code

- Make sure you have a [GitHub account](https://github.com/join)
+You can find issues to work on by looking at the [help wanted](https://github.com/xtermjs/xterm.js/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) or [good first issue](https://github.com/xtermjs/xterm.js/issues?q=is%3Aissue+is%3Aopen+label%3A%22good+first+issue%22) issues. It's a good idea to comment on the issue saying that you're taking it, just in case someone else comes along and you duplicate work. Once you have your issue, here are the steps to contribute:
+
 - Fork [xterm.js](https://github.com/sourcelair/xterm.js/)
  ([how to fork a repo](https://help.github.com/articles/fork-a-repo))
 - Get the [xterm.js demo](https://github.com/xtermjs/xterm.js/wiki/Contributing#running-the-demo) running
@@ -172,6 +172,7 @@ computational environment for Jupyter, supporting interactive data science and s
 - [**Shellvault**](https://www.shellvault.io): The cloud-based SSH terminal you can access from anywhere.
 - [**Juno**](http://junolab.org/): A flexible Julia IDE, based on Atom.
 - [**webssh**](https://github.com/huashengdun/webssh): Web based ssh client.
+- [**info-beamer hosted**](https://info-beamer.com): Uses Xterm.js to manage digital signage devices from the web dashboard.

 [And much more...](https://github.com/xtermjs/xterm.js/network/dependents)

@@ -39,7 +39,7 @@
    "ts-loader": "^4.5.0",
    "tslint": "^5.9.1",
    "tslint-consistent-codestyle": "^1.13.0",
-    "typescript": "3.0",
+    "typescript": "3.1",
    "vinyl-buffer": "^1.0.0",
    "vinyl-source-stream": "^1.1.0",
    "webpack": "^4.17.1",
@@ -5,7 +5,7 @@

 import * as Strings from './Strings';
 import { ITerminal, IBuffer } from './Types';
-import { isMac } from './shared/utils/Browser';
+import { isMac } from './core/Platform';
 import { RenderDebouncer } from './ui/RenderDebouncer';
 import { addDisposableDomListener } from './ui/Lifecycle';
 import { Disposable } from './common/Lifecycle';
@@ -7,9 +7,10 @@ import { CircularList } from './common/CircularList';
 import { CharData, ITerminal, IBuffer, IBufferLine, BufferIndex, IBufferStringIterator, IBufferStringIteratorResult, IBufferLineConstructor } from './Types';
 import { EventEmitter } from './common/EventEmitter';
 import { IMarker } from 'xterm';
-import { BufferLine, BufferLineTypedArray } from './BufferLine';
+import { BufferLine, BufferLineJSArray } from './BufferLine';
+import { DEFAULT_COLOR } from './renderer/atlas/Types';

-export const DEFAULT_ATTR = (0 << 18) | (257 << 9) | (256 << 0);
+export const DEFAULT_ATTR = (0 << 18) | (DEFAULT_COLOR << 9) | (256 << 0);
 export const CHAR_DATA_ATTR_INDEX = 0;
 export const CHAR_DATA_CHAR_INDEX = 1;
 export const CHAR_DATA_WIDTH_INDEX = 2;
@@ -38,6 +39,7 @@ export class Buffer implements IBuffer {
  public tabs: any;
  public savedY: number;
  public savedX: number;
+  public savedCurAttr: number;
  public markers: Marker[] = [];
  private _bufferLineConstructor: IBufferLineConstructor;

@@ -55,9 +57,9 @@ export class Buffer implements IBuffer {
  }

  public setBufferLineFactory(type: string): void {
-    if (type === 'TypedArray') {
-      if (this._bufferLineConstructor !== BufferLineTypedArray) {
-        this._bufferLineConstructor = BufferLineTypedArray;
+    if (type === 'JsArray') {
+      if (this._bufferLineConstructor !== BufferLineJSArray) {
+        this._bufferLineConstructor = BufferLineJSArray;
        this._recreateLines();
      }
    } else {
@@ -113,11 +115,14 @@ export class Buffer implements IBuffer {
  /**
   * Fills the buffer's viewport with blank lines.
   */
-  public fillViewportRows(): void {
+  public fillViewportRows(fillAttr?: number): void {
    if (this.lines.length === 0) {
+      if (fillAttr === undefined) {
+        fillAttr = DEFAULT_ATTR;
+      }
      let i = this._terminal.rows;
      while (i--) {
-        this.lines.push(this.getBlankLine(DEFAULT_ATTR));
+        this.lines.push(this.getBlankLine(fillAttr));
      }
    }
  }
@@ -7,8 +7,10 @@ import { NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR } from './Buffer';

 /**
 * Class representing a terminal line.
+ *
+ * @deprecated to be removed with one of the next releases
 */
-export class BufferLine implements IBufferLine {
+export class BufferLineJSArray implements IBufferLine {
  protected _data: CharData[];
  public isWrapped = false;
  public length: number;
@@ -94,17 +96,14 @@ export class BufferLine implements IBufferLine {
    }
  }

-  public copyFrom(line: IBufferLine): void {
-    this._data = [];
-    for (let i = 0; i < line.length; ++i) {
-      this._push(line.get(i));
-    }
+  public copyFrom(line: BufferLineJSArray): void {
+    this._data = line._data.slice(0);
    this.length = line.length;
    this.isWrapped = line.isWrapped;
  }

  public clone(): IBufferLine {
-    const newLine = new BufferLine(0);
+    const newLine = new BufferLineJSArray(0);
    newLine.copyFrom(this);
    return newLine;
  }
@@ -122,17 +121,8 @@ const enum Cell {

 /**
 * Typed array based bufferline implementation.
- * Note:  Unlike the JS variant the access to the data
- *        via set/get is always a copy action.
- *        Sloppy ref style coding will not work anymore:
- *           line = new BufferLine(10);
- *           char = line.get(0);        // char is a copy
- *           char[some_index] = 123;    // will not update the line
- *           line.set(0, ch);           // do this to update line data
- * TODO:
- *    - provide getData/setData to directly access the data
 */
-export class BufferLineTypedArray implements IBufferLine {
+export class BufferLine implements IBufferLine {
  protected _data: Uint32Array | null = null;
  protected _combined: {[index: number]: string} = {};
  public length: number;
@@ -251,7 +241,7 @@ export class BufferLineTypedArray implements IBufferLine {
  }

  /** alter to a full copy of line  */
-  public copyFrom(line: BufferLineTypedArray): void {
+  public copyFrom(line: BufferLine): void {
    if (this.length !== line.length) {
      this._data = new Uint32Array(line._data);
    } else {
@@ -268,7 +258,7 @@ export class BufferLineTypedArray implements IBufferLine {

  /** create a new clone */
  public clone(): IBufferLine {
-    const newLine = new BufferLineTypedArray(0);
+    const newLine = new BufferLine(0);
    // creation of new typed array from another is actually pretty slow :(
    // still faster than copying values one by one
    newLine._data = new Uint32Array(this._data);
@@ -48,4 +48,30 @@ describe('BufferSet', () => {
      assert.equal(bufferSet.active, bufferSet.alt);
    });
  });
+
+  describe('cursor handling when swapping buffers', () => {
+    beforeEach(() => {
+      bufferSet.normal.x = 0;
+      bufferSet.normal.y = 0;
+      bufferSet.alt.x = 0;
+      bufferSet.alt.y = 0;
+    });
+
+    it('should keep the cursor stationary when activating alt buffer', () => {
+      bufferSet.activateNormalBuffer();
+      bufferSet.active.x = 30;
+      bufferSet.active.y = 10;
+      bufferSet.activateAltBuffer();
+      assert.equal(bufferSet.active.x, 30);
+      assert.equal(bufferSet.active.y, 10);
+    });
+    it('should keep the cursor stationary when activating normal buffer', () => {
+      bufferSet.activateAltBuffer();
+      bufferSet.active.x = 30;
+      bufferSet.active.y = 10;
+      bufferSet.activateNormalBuffer();
+      assert.equal(bufferSet.active.x, 30);
+      assert.equal(bufferSet.active.y, 10);
+    });
+  });
 });
@@ -61,6 +61,8 @@ export class BufferSet extends EventEmitter implements IBufferSet {
    if (this._activeBuffer === this._normal) {
      return;
    }
+    this._normal.x = this._alt.x;
+    this._normal.y = this._alt.y;
    // 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.
@@ -75,13 +77,15 @@ export class BufferSet extends EventEmitter implements IBufferSet {
  /**
   * Sets the alt Buffer of the BufferSet as its currently active Buffer
   */
-  public activateAltBuffer(): void {
+  public activateAltBuffer(fillAttr?: number): void {
    if (this._activeBuffer === this._alt) {
      return;
    }
    // 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._alt.fillViewportRows(fillAttr);
+    this._alt.x = this._normal.x;
+    this._alt.y = this._normal.y;
    this._activeBuffer = this._alt;
    this.emit('activate', {
      activeBuffer: this._alt,
@@ -5,7 +5,7 @@

 import { TestTerminal } from './utils/TestUtils.test';
 import { assert } from 'chai';
-import { getStringCellWidth } from './CharWidth';
+import { getStringCellWidth, wcwidth } from './CharWidth';
 import { IBuffer } from './Types';
 import { CHAR_DATA_WIDTH_INDEX, CHAR_DATA_CHAR_INDEX } from './Buffer';

@@ -77,3 +77,178 @@ describe('getStringCellWidth', function(): void {
  });
  // TODO: multiline tests once #1685 is resolved
 });
+
+it('wcwidth should match all values from the old implementation', function(): void {
+  // old implementation
+  const wcwidthOld = (function(opts: {nul: number, control: number}): (ucs: number) => number {
+    // extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
+    // combining characters
+    const COMBINING_BMP = [
+      [0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
+      [0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
+      [0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
+      [0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
+      [0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
+      [0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
+      [0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
+      [0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
+      [0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
+      [0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
+      [0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
+      [0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
+      [0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
+      [0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
+      [0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
+      [0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
+      [0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
+      [0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
+      [0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
+      [0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
+      [0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
+      [0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
+      [0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
+      [0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
+      [0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
+      [0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
+      [0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
+      [0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
+      [0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
+      [0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
+      [0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
+      [0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
+      [0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
+      [0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
+      [0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
+      [0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
+      [0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
+      [0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
+      [0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
+      [0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
+      [0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
+      [0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
+      [0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB]
+    ];
+    const COMBINING_HIGH = [
+      [0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
+      [0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
+      [0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
+      [0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
+      [0xE0100, 0xE01EF]
+    ];
+    // binary search
+    function bisearch(ucs: number, data: number[][]): boolean {
+      let min = 0;
+      let max = data.length - 1;
+      let mid;
+      if (ucs < data[0][0] || ucs > data[max][1]) {
+        return false;
+      }
+      while (max >= min) {
+        mid = (min + max) >> 1;
+        if (ucs > data[mid][1]) {
+          min = mid + 1;
+        } else if (ucs < data[mid][0]) {
+          max = mid - 1;
+        } else {
+          return true;
+        }
+      }
+      return false;
+    }
+    function wcwidthBMP(ucs: number): number {
+      // test for 8-bit control characters
+      if (ucs === 0) {
+        return opts.nul;
+      }
+      if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0)) {
+        return opts.control;
+      }
+      // binary search in table of non-spacing characters
+      if (bisearch(ucs, COMBINING_BMP)) {
+        return 0;
+      }
+      // if we arrive here, ucs is not a combining or C0/C1 control character
+      if (isWideBMP(ucs)) {
+        return 2;
+      }
+      return 1;
+    }
+    function isWideBMP(ucs: number): boolean {
+      return (
+        ucs >= 0x1100 && (
+        ucs <= 0x115f ||                // Hangul Jamo init. consonants
+        ucs === 0x2329 ||
+        ucs === 0x232a ||
+        (ucs >= 0x2e80 && ucs <= 0xa4cf && ucs !== 0x303f) ||  // CJK..Yi
+        (ucs >= 0xac00 && ucs <= 0xd7a3) ||    // Hangul Syllables
+        (ucs >= 0xf900 && ucs <= 0xfaff) ||    // CJK Compat Ideographs
+        (ucs >= 0xfe10 && ucs <= 0xfe19) ||    // Vertical forms
+        (ucs >= 0xfe30 && ucs <= 0xfe6f) ||    // CJK Compat Forms
+        (ucs >= 0xff00 && ucs <= 0xff60) ||    // Fullwidth Forms
+        (ucs >= 0xffe0 && ucs <= 0xffe6)));
+    }
+    function wcwidthHigh(ucs: number): 0 | 1 | 2 {
+      if (bisearch(ucs, COMBINING_HIGH)) {
+        return 0;
+      }
+      if ((ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd)) {
+        return 2;
+      }
+      return 1;
+    }
+    const control = opts.control | 0;
+    let table: number[] | Uint32Array = null;
+    function initTable(): number[] | Uint32Array {
+      // lookup table for BMP
+      const CODEPOINTS = 65536;  // BMP holds 65536 codepoints
+      const BITWIDTH = 2;        // a codepoint can have a width of 0, 1 or 2
+      const ITEMSIZE = 32;       // using uint32_t
+      const CONTAINERSIZE = CODEPOINTS * BITWIDTH / ITEMSIZE;
+      const CODEPOINTS_PER_ITEM = ITEMSIZE / BITWIDTH;
+      table = (typeof Uint32Array === 'undefined')
+        ? new Array(CONTAINERSIZE)
+        : new Uint32Array(CONTAINERSIZE);
+      for (let i = 0; i < CONTAINERSIZE; ++i) {
+        let num = 0;
+        let pos = CODEPOINTS_PER_ITEM;
+        while (pos--) {
+          num = (num << 2) | wcwidthBMP(CODEPOINTS_PER_ITEM * i + pos);
+        }
+        table[i] = num;
+      }
+      return table;
+    }
+    // get width from lookup table
+    //   position in container   : num / CODEPOINTS_PER_ITEM
+    //     ==> n = table[Math.floor(num / 16)]
+    //     ==> n = table[num >> 4]
+    //   16 codepoints per number:       FFEEDDCCBBAA99887766554433221100
+    //   position in number      : (num % CODEPOINTS_PER_ITEM) * BITWIDTH
+    //     ==> m = (n % 16) * 2
+    //     ==> m = (num & 15) << 1
+    //   right shift to position m
+    //     ==> n = n >> m     e.g. m=12  000000000000FFEEDDCCBBAA99887766
+    //   we are only interested in 2 LSBs, cut off higher bits
+    //     ==> n = n & 3      e.g.       000000000000000000000000000000XX
+    return function (num: number): number {
+      num = num | 0;  // get asm.js like optimization under V8
+      if (num < 32) {
+        return control | 0;
+      }
+      if (num < 127) {
+        return 1;
+      }
+      const t = table || initTable();
+      if (num < 65536) {
+        return t[num >> 4] >> ((num & 15) << 1) & 3;
+      }
+      // do a full search for high codepoints
+      return wcwidthHigh(num);
+    };
+  })({nul: 0, control: 0}); // configurable options
+
+  // test full BMP range old vs new implmenetation
+  for (let i = 0; i < 65536; ++i) {
+    assert.equal(wcwidth(i), wcwidthOld(i), `mismatch for i: ${i}`);
+  }
+});
@@ -3,171 +3,139 @@
 * @license MIT
 */

+import { fill } from './common/TypedArrayUtils';
+
 export const wcwidth = (function(opts: {nul: number, control: number}): (ucs: number) => number {
-    // extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
-    // combining characters
-    const COMBINING_BMP = [
-      [0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
-      [0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
-      [0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
-      [0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
-      [0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
-      [0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
-      [0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
-      [0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
-      [0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
-      [0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
-      [0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
-      [0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
-      [0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
-      [0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
-      [0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
-      [0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
-      [0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
-      [0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
-      [0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
-      [0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
-      [0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
-      [0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
-      [0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
-      [0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
-      [0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
-      [0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
-      [0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
-      [0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
-      [0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
-      [0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
-      [0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
-      [0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
-      [0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
-      [0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
-      [0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
-      [0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
-      [0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
-      [0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
-      [0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
-      [0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
-      [0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
-      [0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
-      [0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB]
-    ];
-    const COMBINING_HIGH = [
-      [0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
-      [0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
-      [0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
-      [0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
-      [0xE0100, 0xE01EF]
-    ];
-    // binary search
-    function bisearch(ucs: number, data: number[][]): boolean {
-      let min = 0;
-      let max = data.length - 1;
-      let mid;
-      if (ucs < data[0][0] || ucs > data[max][1]) {
-        return false;
-      }
-      while (max >= min) {
-        mid = (min + max) >> 1;
-        if (ucs > data[mid][1]) {
-          min = mid + 1;
-        } else if (ucs < data[mid][0]) {
-          max = mid - 1;
-        } else {
-          return true;
-        }
-      }
+  // extracted from https://www.cl.cam.ac.uk/%7Emgk25/ucs/wcwidth.c
+  // combining characters
+  const COMBINING_BMP = [
+    [0x0300, 0x036F], [0x0483, 0x0486], [0x0488, 0x0489],
+    [0x0591, 0x05BD], [0x05BF, 0x05BF], [0x05C1, 0x05C2],
+    [0x05C4, 0x05C5], [0x05C7, 0x05C7], [0x0600, 0x0603],
+    [0x0610, 0x0615], [0x064B, 0x065E], [0x0670, 0x0670],
+    [0x06D6, 0x06E4], [0x06E7, 0x06E8], [0x06EA, 0x06ED],
+    [0x070F, 0x070F], [0x0711, 0x0711], [0x0730, 0x074A],
+    [0x07A6, 0x07B0], [0x07EB, 0x07F3], [0x0901, 0x0902],
+    [0x093C, 0x093C], [0x0941, 0x0948], [0x094D, 0x094D],
+    [0x0951, 0x0954], [0x0962, 0x0963], [0x0981, 0x0981],
+    [0x09BC, 0x09BC], [0x09C1, 0x09C4], [0x09CD, 0x09CD],
+    [0x09E2, 0x09E3], [0x0A01, 0x0A02], [0x0A3C, 0x0A3C],
+    [0x0A41, 0x0A42], [0x0A47, 0x0A48], [0x0A4B, 0x0A4D],
+    [0x0A70, 0x0A71], [0x0A81, 0x0A82], [0x0ABC, 0x0ABC],
+    [0x0AC1, 0x0AC5], [0x0AC7, 0x0AC8], [0x0ACD, 0x0ACD],
+    [0x0AE2, 0x0AE3], [0x0B01, 0x0B01], [0x0B3C, 0x0B3C],
+    [0x0B3F, 0x0B3F], [0x0B41, 0x0B43], [0x0B4D, 0x0B4D],
+    [0x0B56, 0x0B56], [0x0B82, 0x0B82], [0x0BC0, 0x0BC0],
+    [0x0BCD, 0x0BCD], [0x0C3E, 0x0C40], [0x0C46, 0x0C48],
+    [0x0C4A, 0x0C4D], [0x0C55, 0x0C56], [0x0CBC, 0x0CBC],
+    [0x0CBF, 0x0CBF], [0x0CC6, 0x0CC6], [0x0CCC, 0x0CCD],
+    [0x0CE2, 0x0CE3], [0x0D41, 0x0D43], [0x0D4D, 0x0D4D],
+    [0x0DCA, 0x0DCA], [0x0DD2, 0x0DD4], [0x0DD6, 0x0DD6],
+    [0x0E31, 0x0E31], [0x0E34, 0x0E3A], [0x0E47, 0x0E4E],
+    [0x0EB1, 0x0EB1], [0x0EB4, 0x0EB9], [0x0EBB, 0x0EBC],
+    [0x0EC8, 0x0ECD], [0x0F18, 0x0F19], [0x0F35, 0x0F35],
+    [0x0F37, 0x0F37], [0x0F39, 0x0F39], [0x0F71, 0x0F7E],
+    [0x0F80, 0x0F84], [0x0F86, 0x0F87], [0x0F90, 0x0F97],
+    [0x0F99, 0x0FBC], [0x0FC6, 0x0FC6], [0x102D, 0x1030],
+    [0x1032, 0x1032], [0x1036, 0x1037], [0x1039, 0x1039],
+    [0x1058, 0x1059], [0x1160, 0x11FF], [0x135F, 0x135F],
+    [0x1712, 0x1714], [0x1732, 0x1734], [0x1752, 0x1753],
+    [0x1772, 0x1773], [0x17B4, 0x17B5], [0x17B7, 0x17BD],
+    [0x17C6, 0x17C6], [0x17C9, 0x17D3], [0x17DD, 0x17DD],
+    [0x180B, 0x180D], [0x18A9, 0x18A9], [0x1920, 0x1922],
+    [0x1927, 0x1928], [0x1932, 0x1932], [0x1939, 0x193B],
+    [0x1A17, 0x1A18], [0x1B00, 0x1B03], [0x1B34, 0x1B34],
+    [0x1B36, 0x1B3A], [0x1B3C, 0x1B3C], [0x1B42, 0x1B42],
+    [0x1B6B, 0x1B73], [0x1DC0, 0x1DCA], [0x1DFE, 0x1DFF],
+    [0x200B, 0x200F], [0x202A, 0x202E], [0x2060, 0x2063],
+    [0x206A, 0x206F], [0x20D0, 0x20EF], [0x302A, 0x302F],
+    [0x3099, 0x309A], [0xA806, 0xA806], [0xA80B, 0xA80B],
+    [0xA825, 0xA826], [0xFB1E, 0xFB1E], [0xFE00, 0xFE0F],
+    [0xFE20, 0xFE23], [0xFEFF, 0xFEFF], [0xFFF9, 0xFFFB]
+  ];
+  const COMBINING_HIGH = [
+    [0x10A01, 0x10A03], [0x10A05, 0x10A06], [0x10A0C, 0x10A0F],
+    [0x10A38, 0x10A3A], [0x10A3F, 0x10A3F], [0x1D167, 0x1D169],
+    [0x1D173, 0x1D182], [0x1D185, 0x1D18B], [0x1D1AA, 0x1D1AD],
+    [0x1D242, 0x1D244], [0xE0001, 0xE0001], [0xE0020, 0xE007F],
+    [0xE0100, 0xE01EF]
+  ];
+  // binary search
+  function bisearch(ucs: number, data: number[][]): boolean {
+    let min = 0;
+    let max = data.length - 1;
+    let mid;
+    if (ucs < data[0][0] || ucs > data[max][1]) {
      return false;
    }
-    function wcwidthBMP(ucs: number): number {
-      // test for 8-bit control characters
-      if (ucs === 0) {
-        return opts.nul;
-      }
-      if (ucs < 32 || (ucs >= 0x7f && ucs < 0xa0)) {
-        return opts.control;
-      }
-      // binary search in table of non-spacing characters
-      if (bisearch(ucs, COMBINING_BMP)) {
-        return 0;
-      }
-      // if we arrive here, ucs is not a combining or C0/C1 control character
-      if (isWideBMP(ucs)) {
-        return 2;
+    while (max >= min) {
+      mid = (min + max) >> 1;
+      if (ucs > data[mid][1]) {
+        min = mid + 1;
+      } else if (ucs < data[mid][0]) {
+        max = mid - 1;
+      } else {
+        return true;
      }
+    }
+    return false;
+  }
+  function wcwidthHigh(ucs: number): 0 | 1 | 2 {
+    if (bisearch(ucs, COMBINING_HIGH)) {
+      return 0;
+    }
+    if ((ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd)) {
+      return 2;
+    }
+    return 1;
+  }
+  const control = opts.control | 0;
+
+  // create lookup table for BMP plane
+  const table = new Uint8Array(65536);
+  fill(table, 1);
+  table[0] = opts.nul;
+  // control chars
+  fill(table, opts.control, 1, 32);
+  fill(table, opts.control, 0x7f, 0xa0);
+
+  // apply wide char rules first
+  // wide chars
+  fill(table, 2, 0x1100, 0x1160);
+  table[0x2329] = 2;
+  table[0x232a] = 2;
+  fill(table, 2, 0x2e80, 0xa4d0);
+  table[0x303f] = 1;  // wrongly in last line
+
+  fill(table, 2, 0xac00, 0xd7a4);
+  fill(table, 2, 0xf900, 0xfb00);
+  fill(table, 2, 0xfe10, 0xfe1a);
+  fill(table, 2, 0xfe30, 0xfe70);
+  fill(table, 2, 0xff00, 0xff61);
+  fill(table, 2, 0xffe0, 0xffe7);
+
+  // apply combining last to ensure we overwrite
+  // wrongly wide set chars:
+  //    the original algo evals combining first and falls
+  //    through to wide check so we simply do here the opposite
+  // combining 0
+  for (let r = 0; r < COMBINING_BMP.length; ++r) {
+    fill(table, 0, COMBINING_BMP[r][0], COMBINING_BMP[r][1] + 1);
+  }
+
+  return function (num: number): number {
+    if (num < 32) {
+      return control | 0;
+    }
+    if (num < 127) {
      return 1;
    }
-    function isWideBMP(ucs: number): boolean {
-      return (
-        ucs >= 0x1100 && (
-        ucs <= 0x115f ||                // Hangul Jamo init. consonants
-        ucs === 0x2329 ||
-        ucs === 0x232a ||
-        (ucs >= 0x2e80 && ucs <= 0xa4cf && ucs !== 0x303f) ||  // CJK..Yi
-        (ucs >= 0xac00 && ucs <= 0xd7a3) ||    // Hangul Syllables
-        (ucs >= 0xf900 && ucs <= 0xfaff) ||    // CJK Compat Ideographs
-        (ucs >= 0xfe10 && ucs <= 0xfe19) ||    // Vertical forms
-        (ucs >= 0xfe30 && ucs <= 0xfe6f) ||    // CJK Compat Forms
-        (ucs >= 0xff00 && ucs <= 0xff60) ||    // Fullwidth Forms
-        (ucs >= 0xffe0 && ucs <= 0xffe6)));
+    if (num < 65536) {
+      return table[num];
    }
-    function wcwidthHigh(ucs: number): 0 | 1 | 2 {
-      if (bisearch(ucs, COMBINING_HIGH)) {
-        return 0;
-      }
-      if ((ucs >= 0x20000 && ucs <= 0x2fffd) || (ucs >= 0x30000 && ucs <= 0x3fffd)) {
-        return 2;
-      }
-      return 1;
-    }
-    const control = opts.control | 0;
-    let table: number[] | Uint32Array = null;
-    function initTable(): number[] | Uint32Array {
-      // lookup table for BMP
-      const CODEPOINTS = 65536;  // BMP holds 65536 codepoints
-      const BITWIDTH = 2;        // a codepoint can have a width of 0, 1 or 2
-      const ITEMSIZE = 32;       // using uint32_t
-      const CONTAINERSIZE = CODEPOINTS * BITWIDTH / ITEMSIZE;
-      const CODEPOINTS_PER_ITEM = ITEMSIZE / BITWIDTH;
-      table = (typeof Uint32Array === 'undefined')
-        ? new Array(CONTAINERSIZE)
-        : new Uint32Array(CONTAINERSIZE);
-      for (let i = 0; i < CONTAINERSIZE; ++i) {
-        let num = 0;
-        let pos = CODEPOINTS_PER_ITEM;
-        while (pos--) {
-          num = (num << 2) | wcwidthBMP(CODEPOINTS_PER_ITEM * i + pos);
-        }
-        table[i] = num;
-      }
-      return table;
-    }
-    // get width from lookup table
-    //   position in container   : num / CODEPOINTS_PER_ITEM
-    //     ==> n = table[Math.floor(num / 16)]
-    //     ==> n = table[num >> 4]
-    //   16 codepoints per number:       FFEEDDCCBBAA99887766554433221100
-    //   position in number      : (num % CODEPOINTS_PER_ITEM) * BITWIDTH
-    //     ==> m = (n % 16) * 2
-    //     ==> m = (num & 15) << 1
-    //   right shift to position m
-    //     ==> n = n >> m     e.g. m=12  000000000000FFEEDDCCBBAA99887766
-    //   we are only interested in 2 LSBs, cut off higher bits
-    //     ==> n = n & 3      e.g.       000000000000000000000000000000XX
-    return function (num: number): number {
-      num = num | 0;  // get asm.js like optimization under V8
-      if (num < 32) {
-        return control | 0;
-      }
-      if (num < 127) {
-        return 1;
-      }
-      const t = table || initTable();
-      if (num < 65536) {
-        return t[num >> 4] >> ((num & 15) << 1) & 3;
-      }
-      // do a full search for high codepoints
-      return wcwidthHigh(num);
-    };
+    // do a full search for high codepoints
+    return wcwidthHigh(num);
+  };
 })({nul: 0, control: 0});  // configurable options

 /**
@@ -175,17 +143,27 @@ export const wcwidth = (function(opts: {nul: number, control: number}): (ucs: nu
 */
 export function getStringCellWidth(s: string): number {
  let result = 0;
-  for (let i = 0; i < s.length; ++i) {
+  const length = s.length;
+  for (let i = 0; i < length; ++i) {
    let code = s.charCodeAt(i);
+    // surrogate pair first
    if (0xD800 <= code && code <= 0xDBFF) {
-      const low = s.charCodeAt(i + 1);
-      if (isNaN(low)) {
-        return result;
+      if (++i >= length) {
+        // this should not happen with strings retrieved from
+        // Buffer.translateToString as it converts from UTF-32
+        // and therefore always should contain the second part
+        // for any other string we still have to handle it somehow:
+        // simply treat the lonely surrogate first as a single char (UCS-2 behavior)
+        return result + wcwidth(code);
+      }
+      const second = s.charCodeAt(i);
+      // convert surrogate pair to high codepoint only for valid second part (UTF-16)
+      // otherwise treat them independently (UCS-2 behavior)
+      if (0xDC00 <= second && second <= 0xDFFF) {
+        code = (code - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
+      } else {
+        result += wcwidth(second);
      }
-      code = ((code - 0xD800) * 0x400) + (low - 0xDC00) + 0x10000;
-    }
-    if (0xDC00 <= code && code <= 0xDFFF) {
-      continue;
    }
    result += wcwidth(code);
  }
@@ -6,7 +6,7 @@
 import { assert, expect } from 'chai';
 import { InputHandler } from './InputHandler';
 import { MockInputHandlingTerminal } from './utils/TestUtils.test';
-import { NULL_CELL_CHAR, NULL_CELL_CODE, NULL_CELL_WIDTH, CHAR_DATA_CHAR_INDEX } from './Buffer';
+import { NULL_CELL_CHAR, NULL_CELL_CODE, NULL_CELL_WIDTH, CHAR_DATA_CHAR_INDEX, CHAR_DATA_ATTR_INDEX, DEFAULT_ATTR } from './Buffer';
 import { Terminal } from './Terminal';
 import { IBufferLine } from './Types';

@@ -506,4 +506,65 @@ describe('InputHandler', () => {
      inputHandler.print(String.fromCharCode(0x200B), 0, 1);
    });
  });
+
+  describe('alt screen', () => {
+    let term: Terminal;
+    let handler: InputHandler;
+
+    function lineContent(line: IBufferLine): string {
+      let content = '';
+      for (let i = 0; i < line.length; ++i) content += line.get(i)[CHAR_DATA_CHAR_INDEX];
+      return content;
+    }
+
+    beforeEach(() => {
+      term = new Terminal();
+      handler = new InputHandler(term);
+    });
+    it('should handle DECSET/DECRST 47 (alt screen buffer)', () => {
+      handler.parse('\x1b[?47h\r\n\x1b[31mJUNK\x1b[?47lTEST');
+      expect(lineContent(term.buffer.lines.get(0))).to.equal(Array(term.cols + 1).join(' '));
+      expect(lineContent(term.buffer.lines.get(1))).to.equal('    TEST' + Array(term.cols - 7).join(' '));
+      // Text color of 'TEST' should be red
+      expect((term.buffer.lines.get(1).get(4)[CHAR_DATA_ATTR_INDEX] >> 9) & 0x1ff).to.equal(1);
+    });
+    it('should handle DECSET/DECRST 1047 (alt screen buffer)', () => {
+      handler.parse('\x1b[?1047h\r\n\x1b[31mJUNK\x1b[?1047lTEST');
+      expect(lineContent(term.buffer.lines.get(0))).to.equal(Array(term.cols + 1).join(' '));
+      expect(lineContent(term.buffer.lines.get(1))).to.equal('    TEST' + Array(term.cols - 7).join(' '));
+      // Text color of 'TEST' should be red
+      expect((term.buffer.lines.get(1).get(4)[CHAR_DATA_ATTR_INDEX] >> 9) & 0x1ff).to.equal(1);
+    });
+    it('should handle DECSET/DECRST 1048 (alt screen cursor)', () => {
+      handler.parse('\x1b[?1048h\r\n\x1b[31mJUNK\x1b[?1048lTEST');
+      expect(lineContent(term.buffer.lines.get(0))).to.equal('TEST' + Array(term.cols - 3).join(' '));
+      expect(lineContent(term.buffer.lines.get(1))).to.equal('JUNK' + Array(term.cols - 3).join(' '));
+      // Text color of 'TEST' should be default
+      expect(term.buffer.lines.get(0).get(0)[CHAR_DATA_ATTR_INDEX]).to.equal(DEFAULT_ATTR);
+      // Text color of 'JUNK' should be red
+      expect((term.buffer.lines.get(1).get(0)[CHAR_DATA_ATTR_INDEX] >> 9) & 0x1ff).to.equal(1);
+    });
+    it('should handle DECSET/DECRST 1049 (alt screen buffer+cursor)', () => {
+      handler.parse('\x1b[?1049h\r\n\x1b[31mJUNK\x1b[?1049lTEST');
+      expect(lineContent(term.buffer.lines.get(0))).to.equal('TEST' + Array(term.cols - 3).join(' '));
+      expect(lineContent(term.buffer.lines.get(1))).to.equal(Array(term.cols + 1).join(' '));
+      // Text color of 'TEST' should be default
+      expect(term.buffer.lines.get(0).get(0)[CHAR_DATA_ATTR_INDEX]).to.equal(DEFAULT_ATTR);
+    });
+    it('should handle DECSET/DECRST 1049 - maintains saved cursor for alt buffer', () => {
+      handler.parse('\x1b[?1049h\r\n\x1b[31m\x1b[s\x1b[?1049lTEST');
+      expect(lineContent(term.buffer.lines.get(0))).to.equal('TEST' + Array(term.cols - 3).join(' '));
+      // Text color of 'TEST' should be default
+      expect(term.buffer.lines.get(0).get(0)[CHAR_DATA_ATTR_INDEX]).to.equal(DEFAULT_ATTR);
+      handler.parse('\x1b[?1049h\x1b[uTEST');
+      expect(lineContent(term.buffer.lines.get(1))).to.equal('TEST' + Array(term.cols - 3).join(' '));
+      // Text color of 'TEST' should be red
+      expect((term.buffer.lines.get(1).get(0)[CHAR_DATA_ATTR_INDEX] >> 9) & 0x1ff).to.equal(1);
+    });
+    it('should handle DECSET/DECRST 1049 - clears alt buffer with erase attributes', () => {
+      handler.parse('\x1b[42m\x1b[?1049h');
+      // Buffer should be filled with green background
+      expect(term.buffer.lines.get(20).get(10)[CHAR_DATA_ATTR_INDEX] & 0x1ff).to.equal(2);
+    });
+  });
 });
@@ -113,7 +113,7 @@ class DECRQSS implements IDcsHandler {
 * each function's header comment.
 */
 export class InputHandler extends Disposable implements IInputHandler {
-  private _surrogateHigh: string;
+  private _surrogateFirst: string;

  constructor(
      protected _terminal: IInputHandlingTerminal,
@@ -123,7 +123,7 @@ export class InputHandler extends Disposable implements IInputHandler {

    this.register(this._parser);

-    this._surrogateHigh = '';
+    this._surrogateFirst = '';

    /**
     * custom fallback handlers
@@ -311,9 +311,9 @@ export class InputHandler extends Disposable implements IInputHandler {
    }

    // apply leftover surrogate high from last write
-    if (this._surrogateHigh) {
-      data = this._surrogateHigh + data;
-      this._surrogateHigh = '';
+    if (this._surrogateFirst) {
+      data = this._surrogateFirst + data;
+      this._surrogateFirst = '';
    }

    this._parser.parse(data);
@@ -327,7 +327,6 @@ export class InputHandler extends Disposable implements IInputHandler {
  public print(data: string, start: number, end: number): void {
    let char: string;
    let code: number;
-    let low: number;
    let chWidth: number;
    const buffer: IBuffer = this._terminal.buffer;
    const charset: ICharset = this._terminal.charset;
@@ -345,20 +344,25 @@ export class InputHandler extends Disposable implements IInputHandler {

      // surrogate pair handling
      if (0xD800 <= code && code <= 0xDBFF) {
-        // we got a surrogate high
-        // get surrogate low (next 2 bytes)
-        low = data.charCodeAt(stringPosition + 1);
-        if (isNaN(low)) {
-          // end of data stream, save surrogate high
-          this._surrogateHigh = char;
+        if (++stringPosition >= end) {
+          // end of input:
+          // handle pairs as true UTF-16 and wait for the second part
+          // since we expect the input comming from a stream there is
+          // a small chance that the surrogate pair got split
+          // therefore we dont process the first char here, instead
+          // it gets added as first char to the next processed chunk
+          this._surrogateFirst = char;
          continue;
        }
-        code = ((code - 0xD800) * 0x400) + (low - 0xDC00) + 0x10000;
-        char += data.charAt(stringPosition + 1);
-      }
-      // surrogate low - already handled above
-      if (0xDC00 <= code && code <= 0xDFFF) {
-        continue;
+        const second = data.charCodeAt(stringPosition);
+        // if the second part is in surrogate pair range create the high codepoint
+        // otherwise fall back to UCS-2 behavior (handle codepoints independently)
+        if (0xDC00 <= second && second <= 0xDFFF) {
+          code = (code - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
+          char += data.charAt(stringPosition);
+        } else {
+          stringPosition--;
+        }
      }

      // calculate print space
@@ -1280,7 +1284,9 @@ export class InputHandler extends Disposable implements IInputHandler {
        case 66:
          this._terminal.log('Serial port requested application keypad.');
          this._terminal.applicationKeypad = true;
-          this._terminal.viewport.syncScrollArea();
+          if (this._terminal.viewport) {
+            this._terminal.viewport.syncScrollArea();
+          }
          break;
        case 9: // X10 Mouse
          // no release, no motion, no wheel, no modifiers.
@@ -1329,14 +1335,19 @@ export class InputHandler extends Disposable implements IInputHandler {
        case 25: // show cursor
          this._terminal.cursorHidden = false;
          break;
+        case 1048: // alt screen cursor
+          this.saveCursor(params);
+          break;
        case 1049: // alt screen buffer cursor
-          // TODO: Not sure if we need to save/restore after switching the buffer
-          // this.saveCursor(params);
+          this.saveCursor(params);
          // FALL-THROUGH
        case 47: // alt screen buffer
        case 1047: // alt screen buffer
-          this._terminal.buffers.activateAltBuffer();
-          this._terminal.viewport.syncScrollArea();
+          this._terminal.buffers.activateAltBuffer(this._terminal.eraseAttr());
+          this._terminal.refresh(0, this._terminal.rows - 1);
+          if (this._terminal.viewport) {
+            this._terminal.viewport.syncScrollArea();
+          }
          this._terminal.showCursor();
          break;
        case 2004: // bracketed paste mode (https://cirw.in/blog/bracketed-paste)
@@ -1469,7 +1480,9 @@ export class InputHandler extends Disposable implements IInputHandler {
        case 66:
          this._terminal.log('Switching back to normal keypad.');
          this._terminal.applicationKeypad = false;
-          this._terminal.viewport.syncScrollArea();
+          if (this._terminal.viewport) {
+            this._terminal.viewport.syncScrollArea();
+          }
          break;
        case 9: // X10 Mouse
        case 1000: // vt200 mouse
@@ -1497,18 +1510,22 @@ export class InputHandler extends Disposable implements IInputHandler {
        case 25: // hide cursor
          this._terminal.cursorHidden = true;
          break;
+        case 1048: // alt screen cursor
+          this.restoreCursor(params);
+          break;
        case 1049: // alt screen buffer cursor
           // FALL-THROUGH
        case 47: // normal screen buffer
        case 1047: // normal screen buffer - clearing it first
          // Ensure the selection manager has the correct buffer
          this._terminal.buffers.activateNormalBuffer();
-          // TODO: Not sure if we need to save/restore after switching the buffer
-          // if (params[0] === 1049) {
-          //   this.restoreCursor(params);
-          // }
+          if (params[0] === 1049) {
+            this.restoreCursor(params);
+          }
          this._terminal.refresh(0, this._terminal.rows - 1);
-          this._terminal.viewport.syncScrollArea();
+          if (this._terminal.viewport) {
+            this._terminal.viewport.syncScrollArea();
+          }
          this._terminal.showCursor();
          break;
        case 2004: // bracketed paste mode (https://cirw.in/blog/bracketed-paste)
@@ -1787,7 +1804,9 @@ export class InputHandler extends Disposable implements IInputHandler {
      this._terminal.originMode = false;
      this._terminal.wraparoundMode = true;  // defaults: xterm - true, vt100 - false
      this._terminal.applicationKeypad = false; // ?
-      this._terminal.viewport.syncScrollArea();
+      if (this._terminal.viewport) {
+        this._terminal.viewport.syncScrollArea();
+      }
      this._terminal.applicationCursor = false;
      this._terminal.buffer.scrollTop = 0;
      this._terminal.buffer.scrollBottom = this._terminal.rows - 1;
@@ -1854,7 +1873,7 @@ export class InputHandler extends Disposable implements IInputHandler {
  public saveCursor(params: number[]): void {
    this._terminal.buffer.savedX = this._terminal.buffer.x;
    this._terminal.buffer.savedY = this._terminal.buffer.y;
-    this._terminal.savedCurAttr = this._terminal.curAttr;
+    this._terminal.buffer.savedCurAttr = this._terminal.curAttr;
  }


@@ -1866,7 +1885,7 @@ export class InputHandler extends Disposable implements IInputHandler {
  public restoreCursor(params: number[]): void {
    this._terminal.buffer.x = this._terminal.buffer.savedX || 0;
    this._terminal.buffer.y = this._terminal.buffer.savedY || 0;
-    this._terminal.curAttr = this._terminal.savedCurAttr || DEFAULT_ATTR;
+    this._terminal.curAttr = this._terminal.buffer.savedCurAttr || DEFAULT_ATTR;
  }


@@ -30,6 +30,7 @@ class TestSelectionManager extends SelectionManager {

  public selectLineAt(line: number): void { this._selectLineAt(line); }
  public selectWordAt(coords: [number, number]): void { this._selectWordAt(coords, true); }
+  public areCoordsInSelection(coords: [number, number], start: [number, number], end: [number, number]): boolean { return this._areCoordsInSelection(coords, start, end); }

  // Disable DOM interaction
  public enable(): void {}
@@ -478,5 +479,17 @@ describe('SelectionManager', () => {
      assert.equal(selectionManager.selectionText, 'a\n😁\nc');
    });
  });
+
+  describe('_areCoordsInSelection', () => {
+    it('should return whether coords are in the selection', () => {
+      assert.isFalse(selectionManager.areCoordsInSelection([0, 0], [2, 0], [2, 1]));
+      assert.isFalse(selectionManager.areCoordsInSelection([1, 0], [2, 0], [2, 1]));
+      assert.isTrue(selectionManager.areCoordsInSelection([2, 0], [2, 0], [2, 1]));
+      assert.isTrue(selectionManager.areCoordsInSelection([10, 0], [2, 0], [2, 1]));
+      assert.isTrue(selectionManager.areCoordsInSelection([0, 1], [2, 0], [2, 1]));
+      assert.isTrue(selectionManager.areCoordsInSelection([1, 1], [2, 0], [2, 1]));
+      assert.isFalse(selectionManager.areCoordsInSelection([2, 1], [2, 0], [2, 1]));
+    });
+  });
 });

@@ -6,7 +6,7 @@
 import { ITerminal, ISelectionManager, IBuffer, CharData, IBufferLine } from './Types';
 import { XtermListener } from './common/Types';
 import { MouseHelper } from './utils/MouseHelper';
-import * as Browser from './shared/utils/Browser';
+import * as Browser from './core/Platform';
 import { CharMeasure } from './ui/CharMeasure';
 import { EventEmitter } from './common/EventEmitter';
 import { SelectionModel } from './SelectionModel';
@@ -289,9 +289,14 @@ export class SelectionManager extends EventEmitter implements ISelectionManager
      return false;
    }

+    return this._areCoordsInSelection(coords, start, end);
+  }
+
+  protected _areCoordsInSelection(coords: [number, number], start: [number, number], end: [number, number]): boolean {
    return (coords[1] > start[1] && coords[1] < end[1]) ||
-        (start[1] === end[1] && coords[1] === start[1] && coords[0] > start[0] && coords[0] < end[0]) ||
-        (start[1] < end[1] && coords[1] === end[1] && coords[0] < end[0]);
+        (start[1] === end[1] && coords[1] === start[1] && coords[0] >= start[0] && coords[0] < end[0]) ||
+        (start[1] < end[1] && coords[1] === end[1] && coords[0] < end[0]) ||
+        (start[1] < end[1] && coords[1] === start[1] && coords[0] >= start[0]);
  }

  /**
@@ -342,7 +347,7 @@ export class SelectionManager extends EventEmitter implements ISelectionManager
   * @param event The mouse event.
   */
  private _getMouseBufferCoords(event: MouseEvent): [number, number] {
-    const coords = this._terminal.mouseHelper.getCoords(event, this._terminal.screenElement, this._charMeasure, this._terminal.options.lineHeight, this._terminal.cols, this._terminal.rows, true);
+    const coords = this._terminal.mouseHelper.getCoords(event, this._terminal.screenElement, this._charMeasure, this._terminal.cols, this._terminal.rows, true);
    if (!coords) {
      return null;
    }
@@ -12,7 +12,19 @@ import { ITerminal, ISoundManager } from './Types';
 export const DEFAULT_BELL_SOUND = 'data:audio/wav;base64,UklGRigBAABXQVZFZm10IBAAAAABAAEARKwAAIhYAQACABAAZGF0YQQBAADpAFgCwAMlBZoG/wdmCcoKRAypDQ8PbRDBEQQTOxRtFYcWlBePGIUZXhoiG88bcBz7HHIdzh0WHlMeZx51HmkeUx4WHs8dah0AHXwc3hs9G4saxRnyGBIYGBcQFv8U4RPAEoYRQBACD70NWwwHC6gJOwjWBloF7gOBAhABkf8b/qv8R/ve+Xf4Ife79W/0JfPZ8Z/wde9N7ijtE+wU6xvqM+lb6H7nw+YX5mrlxuQz5Mzje+Ma49fioeKD4nXiYeJy4pHitOL04j/jn+MN5IPkFOWs5U3mDefM55/ogOl36m7rdOyE7abuyu8D8Unyj/Pg9D/2qfcb+Yn6/vuK/Qj/lAAlAg==';

 export class SoundManager implements ISoundManager {
-  private _audioContext: AudioContext;
+  private static _audioContext: AudioContext;
+
+  static get audioContext(): AudioContext | null {
+    if (!SoundManager._audioContext) {
+      const audioContextCtor: typeof AudioContext = (<any>window).AudioContext || (<any>window).webkitAudioContext;
+      if (!audioContextCtor) {
+        console.warn('Web Audio API is not supported by this browser. Consider upgrading to the latest version');
+        return null;
+      }
+      SoundManager._audioContext = new audioContextCtor();
+    }
+    return SoundManager._audioContext;
+  }

  constructor(
    private _terminal: ITerminal
@@ -20,22 +32,16 @@ export class SoundManager implements ISoundManager {
  }

  public playBellSound(): void {
-    const audioContextCtor: typeof AudioContext = (<any>window).AudioContext || (<any>window).webkitAudioContext;
-    if (!this._audioContext && audioContextCtor) {
-      this._audioContext = new audioContextCtor();
-    }
-
-    if (this._audioContext) {
-      const bellAudioSource = this._audioContext.createBufferSource();
-      const context = this._audioContext;
-      this._audioContext.decodeAudioData(this._base64ToArrayBuffer(this._removeMimeType(this._terminal.options.bellSound)), (buffer) => {
-        bellAudioSource.buffer = buffer;
-        bellAudioSource.connect(context.destination);
-        bellAudioSource.start(0);
-      });
-    } else {
-      console.warn('Sorry, but the Web Audio API is not supported by your browser. Please, consider upgrading to the latest version');
+    const ctx = SoundManager.audioContext;
+    if (!ctx) {
+      return;
    }
+    const bellAudioSource = ctx.createBufferSource();
+    ctx.decodeAudioData(this._base64ToArrayBuffer(this._removeMimeType(this._terminal.options.bellSound)), (buffer) => {
+      bellAudioSource.buffer = buffer;
+      bellAudioSource.connect(ctx.destination);
+      bellAudioSource.start(0);
+    });
  }

  private _base64ToArrayBuffer(base64: string): ArrayBuffer {
@@ -21,22 +21,22 @@
 *   http://linux.die.net/man/7/urxvt
 */

-import { IInputHandlingTerminal, IViewport, ICompositionHelper, ITerminalOptions, ITerminal, IBrowser, ILinkifier, ILinkMatcherOptions, CustomKeyEventHandler, LinkMatcherHandler, CharData, CharacterJoinerHandler } from './Types';
+import { IInputHandlingTerminal, IViewport, ICompositionHelper, ITerminalOptions, ITerminal, IBrowser, ILinkifier, ILinkMatcherOptions, CustomKeyEventHandler, LinkMatcherHandler, CharData, CharacterJoinerHandler, IBufferLine } from './Types';
 import { IMouseZoneManager } from './ui/Types';
 import { IRenderer } from './renderer/Types';
 import { BufferSet } from './BufferSet';
-import { Buffer, MAX_BUFFER_SIZE, DEFAULT_ATTR, NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR } from './Buffer';
+import { Buffer, MAX_BUFFER_SIZE, DEFAULT_ATTR, NULL_CELL_CODE, NULL_CELL_WIDTH, NULL_CELL_CHAR, CHAR_DATA_ATTR_INDEX } from './Buffer';
 import { CompositionHelper } from './CompositionHelper';
 import { EventEmitter } from './common/EventEmitter';
 import { Viewport } from './Viewport';
-import { rightClickHandler, moveTextAreaUnderMouseCursor, pasteHandler, copyHandler } from './handlers/Clipboard';
+import { rightClickHandler, moveTextAreaUnderMouseCursor, pasteHandler, copyHandler } from './ui/Clipboard';
 import { C0 } from './common/data/EscapeSequences';
 import { InputHandler } from './InputHandler';
 import { Renderer } from './renderer/Renderer';
 import { Linkifier } from './Linkifier';
 import { SelectionManager } from './SelectionManager';
 import { CharMeasure } from './ui/CharMeasure';
-import * as Browser from './shared/utils/Browser';
+import * as Browser from './core/Platform';
 import { addDisposableDomListener } from './ui/Lifecycle';
 import * as Strings from './Strings';
 import { MouseHelper } from './utils/MouseHelper';
@@ -106,7 +106,7 @@ const DEFAULT_OPTIONS: ITerminalOptions = {
  theme: null,
  rightClickSelectsWord: Browser.isMac,
  rendererType: 'canvas',
-  experimentalBufferLineImpl: 'JsArray'
+  experimentalBufferLineImpl: 'TypedArray'
 };

 export class Terminal extends EventEmitter implements ITerminal, IDisposable, IInputHandlingTerminal {
@@ -170,7 +170,6 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
  public savedCols: number;

  public curAttr: number;
-  public savedCurAttr: number;

  public params: (string | number)[];
  public currentParam: string | number;
@@ -208,6 +207,9 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
  private _screenDprMonitor: ScreenDprMonitor;
  private _theme: ITheme;

+  // bufferline to clone/copy from for new blank lines
+  private _blankLine: IBufferLine = null;
+
  public cols: number;
  public rows: number;

@@ -497,6 +499,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
      case 'experimentalBufferLineImpl':
        this.buffers.normal.setBufferLineFactory(value);
        this.buffers.alt.setBufferLineFactory(value);
+        this._blankLine = null;
        break;
    }
    // Inform renderer of changes
@@ -804,7 +807,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
      button = getButton(ev);

      // get mouse coordinates
-      pos = self.mouseHelper.getRawByteCoords(ev, self.screenElement, self.charMeasure, self.options.lineHeight, self.cols, self.rows);
+      pos = self.mouseHelper.getRawByteCoords(ev, self.screenElement, self.charMeasure, self.cols, self.rows);
      if (!pos) return;

      sendEvent(button, pos);
@@ -830,7 +833,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
    // ^[[M 3<^[[M@4<^[[M@5<^[[M@6<^[[M@7<^[[M#7<
    function sendMove(ev: MouseEvent): void {
      let button = pressed;
-      const pos = self.mouseHelper.getRawByteCoords(ev, self.screenElement, self.charMeasure, self.options.lineHeight, self.cols, self.rows);
+      const pos = self.mouseHelper.getRawByteCoords(ev, self.screenElement, self.charMeasure, self.cols, self.rows);
      if (!pos) return;

      // buttons marked as motions
@@ -1154,9 +1157,9 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
   */
  public updateCursorStyle(ev: KeyboardEvent): void {
    if (this.selectionManager && this.selectionManager.shouldColumnSelect(ev)) {
-      this.element.classList.add('xterm-cursor-crosshair');
+      this.element.classList.add('column-select');
    } else {
-      this.element.classList.remove('xterm-cursor-crosshair');
+      this.element.classList.remove('column-select');
    }
  }

@@ -1174,20 +1177,40 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
   * Scroll the terminal down 1 row, creating a blank line.
   * @param isWrapped Whether the new line is wrapped from the previous line.
   */
-  public scroll(isWrapped?: boolean): void {
-    const newLine = this.buffer.getBlankLine(this.eraseAttr(), isWrapped);
+  public scroll(isWrapped: boolean = false): void {
+    let newLine: IBufferLine;
+    const useRecycling = this.options.experimentalBufferLineImpl !== 'JsArray';
+    if (useRecycling) {
+      newLine = this._blankLine;
+      if (!newLine || newLine.length !== this.cols || newLine.get(0)[CHAR_DATA_ATTR_INDEX] !== this.eraseAttr()) {
+        newLine = this.buffer.getBlankLine(this.eraseAttr(), isWrapped);
+        this._blankLine = newLine;
+      }
+      newLine.isWrapped = isWrapped;
+    } else {
+      newLine = this.buffer.getBlankLine(this.eraseAttr(), isWrapped);
+    }
+
    const topRow = this.buffer.ybase + this.buffer.scrollTop;
    const bottomRow = this.buffer.ybase + this.buffer.scrollBottom;

    if (this.buffer.scrollTop === 0) {
      // Determine whether the buffer is going to be trimmed after insertion.
-      const willBufferBeTrimmed = this.buffer.lines.length === this.buffer.lines.maxLength;
+      const willBufferBeTrimmed = this.buffer.lines.isFull;

      // Insert the line using the fastest method
      if (bottomRow === this.buffer.lines.length - 1) {
-        this.buffer.lines.push(newLine);
+        if (useRecycling) {
+          if (willBufferBeTrimmed) {
+            this.buffer.lines.recycle().copyFrom(newLine);
+          } else {
+            this.buffer.lines.push(newLine.clone());
+          }
+        } else {
+          this.buffer.lines.push(newLine);
+        }
      } else {
-        this.buffer.lines.splice(bottomRow + 1, 0, newLine);
+        this.buffer.lines.splice(bottomRow + 1, 0, (useRecycling) ? newLine.clone() : newLine);
      }

      // Only adjust ybase and ydisp when the buffer is not trimmed
@@ -1209,7 +1232,7 @@ export class Terminal extends EventEmitter implements ITerminal, IDisposable, II
      // scrollback, instead we can just shift them in-place.
      const scrollRegionHeight = bottomRow - topRow + 1/*as it's zero-based*/;
      this.buffer.lines.shiftElements(topRow + 1, scrollRegionHeight - 1, -1);
-      this.buffer.lines.set(bottomRow, newLine);
+      this.buffer.lines.set(bottomRow, (useRecycling) ? newLine.clone() : newLine);
    }

    // Move the viewport to the bottom of the buffer unless the user is
@@ -49,7 +49,6 @@ export interface IInputHandlingTerminal extends IEventEmitter {
  wraparoundMode: boolean;
  bracketedPasteMode: boolean;
  curAttr: number;
-  savedCurAttr: number;
  savedCols: number;
  x10Mouse: boolean;
  vt200Mouse: boolean;
@@ -246,8 +245,8 @@ export interface ILinkifierAccessor {
 }

 export interface IMouseHelper {
-  getCoords(event: { clientX: number, clientY: number }, element: HTMLElement, charMeasure: ICharMeasure, lineHeight: number, colCount: number, rowCount: number, isSelection?: boolean): [number, number];
-  getRawByteCoords(event: MouseEvent, element: HTMLElement, charMeasure: ICharMeasure, lineHeight: number, colCount: number, rowCount: number): { x: number, y: number };
+  getCoords(event: { clientX: number, clientY: number }, element: HTMLElement, charMeasure: ICharMeasure, colCount: number, rowCount: number, isSelection?: boolean): [number, number];
+  getRawByteCoords(event: MouseEvent, element: HTMLElement, charMeasure: ICharMeasure, colCount: number, rowCount: number): { x: number, y: number };
 }

 export interface ICharMeasure {
@@ -290,6 +289,7 @@ export interface IBuffer {
  hasScrollback: boolean;
  savedY: number;
  savedX: number;
+  savedCurAttr: number;
  isCursorInViewport: boolean;
  translateBufferLineToString(lineIndex: number, trimRight: boolean, startCol?: number, endCol?: number): string;
  getWrappedRangeForLine(y: number): { first: number, last: number };
@@ -306,7 +306,7 @@ export interface IBufferSet extends IEventEmitter {
  active: IBuffer;

  activateNormalBuffer(): void;
-  activateAltBuffer(): void;
+  activateAltBuffer(fillAttr?: number): void;
 }

 export interface ISelectionManager {
@@ -3,7 +3,7 @@
 * @license MIT
 */

-import { assert, expect } from 'chai';
+import { assert } from 'chai';

 import * as attach from './attach';

@@ -3,7 +3,7 @@
 * @license MIT
 */

-import { assert, expect } from 'chai';
+import { assert } from 'chai';

 import * as fit from './fit';

@@ -3,7 +3,7 @@
 * @license MIT
 */

-import { assert, expect } from 'chai';
+import { assert } from 'chai';

 import * as fullscreen from './fullscreen';

--- a/Show More
+++ b/Show More