src/SelectionManager.ts

   1 /**
   2  * @license MIT
   3  */
   4
   5 import * as Mouse from './utils/Mouse';
   6 import * as Browser from './utils/Browser';
   7 import { CharMeasure } from './utils/CharMeasure';
   8 import { CircularList } from './utils/CircularList';
   9 import { EventEmitter } from './EventEmitter';
  10 import { ITerminal } from './Interfaces';
  11 import { SelectionModel } from './SelectionModel';
  12
  13 /**
  14  * The number of pixels the mouse needs to be above or below the viewport in
  15  * order to scroll at the maximum speed.
  16  */
  17 const DRAG_SCROLL_MAX_THRESHOLD = 50;
  18
  19 /**
  20  * The maximum scrolling speed
  21  */
  22 const DRAG_SCROLL_MAX_SPEED = 15;
  23
  24 /**
  25  * The number of milliseconds between drag scroll updates.
  26  */
  27 const DRAG_SCROLL_INTERVAL = 50;
  28
  29 /**
  30  * The amount of time before mousedown events are no longer stacked to create
  31  * double/triple click events.
  32  */
  33 const CLEAR_MOUSE_DOWN_TIME = 400;
  34
  35 /**
  36  * The number of pixels in each direction that the mouse must move before
  37  * mousedown events are no longer stacked to create double/triple click events.
  38  */
  39 const CLEAR_MOUSE_DISTANCE = 10;
  40
  41 /**
  42  * A string containing all characters that are considered word separated by the
  43  * double click to select work logic.
  44  */
  45 const WORD_SEPARATORS = ' ()[]{}:\'"';
  46
  47 // TODO: Move these constants elsewhere, they belong in a buffer or buffer
  48 //       data/line class.
  49 const LINE_DATA_CHAR_INDEX = 1;
  50 const LINE_DATA_WIDTH_INDEX = 2;
  51
  52 const NON_BREAKING_SPACE_CHAR = String.fromCharCode(160);
  53 const ALL_NON_BREAKING_SPACE_REGEX = new RegExp(NON_BREAKING_SPACE_CHAR, 'g');
  54
  55 /**
  56  * Represents a position of a word on a line.
  57  */
  58 interface IWordPosition {
  59   start: number;
  60   length: number;
  61 }
  62
  63 /**
  64  * A selection mode, this drives how the selection behaves on mouse move.
  65  */
  66 enum SelectionMode {
  67   NORMAL,
  68   WORD,
  69   LINE
  70 }
  71
  72 /**
  73  * A class that manages the selection of the terminal. With help from
  74  * SelectionModel, SelectionManager handles with all logic associated with
  75  * dealing with the selection, including handling mouse interaction, wide
  76  * characters and fetching the actual text within the selection. Rendering is
  77  * not handled by the SelectionManager but a 'refresh' event is fired when the
  78  * selection is ready to be redrawn.
  79  */
  80 export class SelectionManager extends EventEmitter {
  81   protected _model: SelectionModel;
  82
  83   /**
  84    * The amount to scroll every drag scroll update (depends on how far the mouse
  85    * drag is above or below the terminal).
  86    */
  87   private _dragScrollAmount: number;
  88
  89   /**
  90    * The last time the mousedown event fired, this is used to track double and
  91    * triple clicks.
  92    */
  93   private _lastMouseDownTime: number;
  94
  95   /**
  96    * The last position the mouse was clicked [x, y].
  97    */
  98   private _lastMousePosition: [number, number];
  99
 100   /**
 101    * The number of clicks of the mousedown event. This is used to keep track of
 102    * double and triple clicks.
 103    */
 104   private _clickCount: number;
 105
 106   /**
 107    * The current selection mode.
 108    */
 109   private _activeSelectionMode: SelectionMode;
 110
 111   /**
 112    * A setInterval timer that is active while the mouse is down whose callback
 113    * scrolls the viewport when necessary.
 114    */
 115   private _dragScrollIntervalTimer: NodeJS.Timer;
 116
 117   /**
 118    * The animation frame ID used for refreshing the selection.
 119    */
 120   private _refreshAnimationFrame: number;
 121
 122   private _bufferTrimListener: any;
 123   private _mouseMoveListener: EventListener;
 124   private _mouseDownListener: EventListener;
 125   private _mouseUpListener: EventListener;
 126
 127   constructor(
 128     private _terminal: ITerminal,
 129     private _buffer: CircularList<any>,
 130     private _rowContainer: HTMLElement,
 131     private _charMeasure: CharMeasure
 132   ) {
 133     super();
 134     this._initListeners();
 135     this.enable();
 136
 137     this._model = new SelectionModel(_terminal);
 138     this._lastMouseDownTime = 0;
 139     this._activeSelectionMode = SelectionMode.NORMAL;
 140   }
 141
 142   /**
 143    * Initializes listener variables.
 144    */
 145   private _initListeners() {
 146     this._bufferTrimListener = (amount: number) => this._onTrim(amount);
 147     this._mouseMoveListener = event => this._onMouseMove(<MouseEvent>event);
 148     this._mouseDownListener = event => this._onMouseDown(<MouseEvent>event);
 149     this._mouseUpListener = event => this._onMouseUp(<MouseEvent>event);
 150   }
 151
 152   /**
 153    * Disables the selection manager. This is useful for when terminal mouse
 154    * are enabled.
 155    */
 156   public disable() {
 157     this.clearSelection();
 158     this._buffer.off('trim', this._bufferTrimListener);
 159     this._rowContainer.removeEventListener('mousedown', this._mouseDownListener);
 160   }
 161
 162   /**
 163    * Enable the selection manager.
 164    */
 165   public enable() {
 166     // Only adjust the selection on trim, shiftElements is rarely used (only in
 167     // reverseIndex) and delete in a splice is only ever used when the same
 168     // number of elements was just added. Given this is could actually be
 169     // beneficial to leave the selection as is for these cases.
 170     this._buffer.on('trim', this._bufferTrimListener);
 171     this._rowContainer.addEventListener('mousedown', this._mouseDownListener);
 172   }
 173
 174   /**
 175    * Sets the active buffer, this should be called when the alt buffer is
 176    * switched in or out.
 177    * @param buffer The active buffer.
 178    */
 179   public setBuffer(buffer: CircularList<any>): void {
 180     this._buffer = buffer;
 181   }
 182
 183   /**
 184    * Gets whether there is an active text selection.
 185    */
 186   public get hasSelection(): boolean {
 187     const start = this._model.finalSelectionStart;
 188     const end = this._model.finalSelectionEnd;
 189     if (!start || !end) {
 190       return false;
 191     }
 192     return start[0] !== end[0] || start[1] !== end[1];
 193   }
 194
 195   /**
 196    * Gets the text currently selected.
 197    */
 198   public get selectionText(): string {
 199     const start = this._model.finalSelectionStart;
 200     const end = this._model.finalSelectionEnd;
 201     if (!start || !end) {
 202       return '';
 203     }
 204
 205     // Get first row
 206     const startRowEndCol = start[1] === end[1] ? end[0] : null;
 207     let result: string[] = [];
 208     result.push(this._translateBufferLineToString(this._buffer.get(start[1]), true, start[0], startRowEndCol));
 209
 210     // Get middle rows
 211     for (let i = start[1] + 1; i <= end[1] - 1; i++) {
 212       const bufferLine = this._buffer.get(i);
 213       const lineText = this._translateBufferLineToString(bufferLine, true);
 214       if (bufferLine.isWrapped) {
 215         result[result.length - 1] += lineText;
 216       } else {
 217         result.push(lineText);
 218       }
 219     }
 220
 221     // Get final row
 222     if (start[1] !== end[1]) {
 223       const bufferLine = this._buffer.get(end[1]);
 224       const lineText = this._translateBufferLineToString(bufferLine, true, 0, end[0]);
 225       if (bufferLine.isWrapped) {
 226         result[result.length - 1] += lineText;
 227       } else {
 228         result.push(lineText);
 229       }
 230     }
 231
 232     // Format string by replacing non-breaking space chars with regular spaces
 233     // and joining the array into a multi-line string.
 234     const formattedResult = result.map(line => {
 235       return line.replace(ALL_NON_BREAKING_SPACE_REGEX, ' ');
 236     }).join('\n');
 237
 238     return formattedResult;
 239   }
 240
 241   /**
 242    * Clears the current terminal selection.
 243    */
 244   public clearSelection(): void {
 245     this._model.clearSelection();
 246     this._removeMouseDownListeners();
 247     this.refresh();
 248   }
 249
 250   /**
 251    * Translates a buffer line to a string, with optional start and end columns.
 252    * Wide characters will count as two columns in the resulting string. This
 253    * function is useful for getting the actual text underneath the raw selection
 254    * position.
 255    * @param line The line being translated.
 256    * @param trimRight Whether to trim whitespace to the right.
 257    * @param startCol The column to start at.
 258    * @param endCol The column to end at.
 259    */
 260   private _translateBufferLineToString(line: any, trimRight: boolean, startCol: number = 0, endCol: number = null): string {
 261     // TODO: This function should live in a buffer or buffer line class
 262
 263     // Get full line
 264     let lineString = '';
 265     let widthAdjustedStartCol = startCol;
 266     let widthAdjustedEndCol = endCol;
 267     for (let i = 0; i < line.length; i++) {
 268       const char = line[i];
 269       lineString += char[LINE_DATA_CHAR_INDEX];
 270       // Adjust start and end cols for wide characters if they affect their
 271       // column indexes
 272       if (char[LINE_DATA_WIDTH_INDEX] === 0) {
 273         if (startCol >= i) {
 274           widthAdjustedStartCol--;
 275         }
 276         if (endCol >= i) {
 277           widthAdjustedEndCol--;
 278         }
 279       }
 280     }
 281
 282     // Calculate the final end col by trimming whitespace on the right of the
 283     // line if needed.
 284     let finalEndCol = widthAdjustedEndCol || line.length;
 285     if (trimRight) {
 286       const rightWhitespaceIndex = lineString.search(/\s+$/);
 287       if (rightWhitespaceIndex !== -1) {
 288         finalEndCol = Math.min(finalEndCol, rightWhitespaceIndex);
 289       }
 290       // Return the empty string if only trimmed whitespace is selected
 291       if (finalEndCol <= widthAdjustedStartCol) {
 292         return '';
 293       }
 294     }
 295
 296     return lineString.substring(widthAdjustedStartCol, finalEndCol);
 297   }
 298
 299   /**
 300    * Queues a refresh, redrawing the selection on the next opportunity.
 301    * @param isNewSelection Whether the selection should be registered as a new
 302    * selection on Linux.
 303    */
 304   public refresh(isNewSelection?: boolean): void {
 305     // Queue the refresh for the renderer
 306     if (!this._refreshAnimationFrame) {
 307       this._refreshAnimationFrame = window.requestAnimationFrame(() => this._refresh());
 308     }
 309
 310     // If the platform is Linux and the refresh call comes from a mouse event,
 311     // we need to update the selection for middle click to paste selection.
 312     if (Browser.isLinux && isNewSelection) {
 313       const selectionText = this.selectionText;
 314       if (selectionText.length) {
 315         this.emit('newselection', this.selectionText);
 316       }
 317     }
 318   }
 319
 320   /**
 321    * Fires the refresh event, causing consumers to pick it up and redraw the
 322    * selection state.
 323    */
 324   private _refresh(): void {
 325     this._refreshAnimationFrame = null;
 326     this.emit('refresh', { start: this._model.finalSelectionStart, end: this._model.finalSelectionEnd });
 327   }
 328
 329   /**
 330    * Selects all text within the terminal.
 331    */
 332   public selectAll(): void {
 333     this._model.isSelectAllActive = true;
 334     this.refresh();
 335   }
 336
 337   /**
 338    * Handle the buffer being trimmed, adjust the selection position.
 339    * @param amount The amount the buffer is being trimmed.
 340    */
 341   private _onTrim(amount: number) {
 342     const needsRefresh = this._model.onTrim(amount);
 343     if (needsRefresh) {
 344       this.refresh();
 345     }
 346   }
 347
 348   /**
 349    * Gets the 0-based [x, y] buffer coordinates of the current mouse event.
 350    * @param event The mouse event.
 351    */
 352   private _getMouseBufferCoords(event: MouseEvent): [number, number] {
 353     const coords = Mouse.getCoords(event, this._rowContainer, this._charMeasure, this._terminal.cols, this._terminal.rows, true);
 354     // Convert to 0-based
 355     coords[0]--;
 356     coords[1]--;
 357     // Convert viewport coords to buffer coords
 358     coords[1] += this._terminal.ydisp;
 359     return coords;
 360   }
 361
 362   /**
 363    * Gets the amount the viewport should be scrolled based on how far out of the
 364    * terminal the mouse is.
 365    * @param event The mouse event.
 366    */
 367   private _getMouseEventScrollAmount(event: MouseEvent): number {
 368     let offset = Mouse.getCoordsRelativeToElement(event, this._rowContainer)[1];
 369     const terminalHeight = this._terminal.rows * this._charMeasure.height;
 370     if (offset >= 0 && offset <= terminalHeight) {
 371       return 0;
 372     }
 373     if (offset > terminalHeight) {
 374       offset -= terminalHeight;
 375     }
 376
 377     offset = Math.min(Math.max(offset, -DRAG_SCROLL_MAX_THRESHOLD), DRAG_SCROLL_MAX_THRESHOLD);
 378     offset /= DRAG_SCROLL_MAX_THRESHOLD;
 379     return (offset / Math.abs(offset)) + Math.round(offset * (DRAG_SCROLL_MAX_SPEED - 1));
 380   }
 381
 382   /**
 383    * Handles te mousedown event, setting up for a new selection.
 384    * @param event The mousedown event.
 385    */
 386   private _onMouseDown(event: MouseEvent) {
 387     // Only action the primary button
 388     if (event.button !== 0) {
 389       return;
 390     }
 391
 392     // Tell the browser not to start a regular selection
 393     event.preventDefault();
 394
 395     // Reset drag scroll state
 396     this._dragScrollAmount = 0;
 397
 398     this._setMouseClickCount(event);
 399
 400     if (event.shiftKey) {
 401       this._onShiftClick(event);
 402     } else {
 403       if (this._clickCount === 1) {
 404           this._onSingleClick(event);
 405       } else if (this._clickCount === 2) {
 406           this._onDoubleClick(event);
 407       } else if (this._clickCount === 3) {
 408           this._onTripleClick(event);
 409       }
 410     }
 411
 412     this._addMouseDownListeners();
 413     this.refresh(true);
 414   }
 415
 416   /**
 417    * Adds listeners when mousedown is triggered.
 418    */
 419   private _addMouseDownListeners(): void {
 420     // Listen on the document so that dragging outside of viewport works
 421     this._rowContainer.ownerDocument.addEventListener('mousemove', this._mouseMoveListener);
 422     this._rowContainer.ownerDocument.addEventListener('mouseup', this._mouseUpListener);
 423     this._dragScrollIntervalTimer = setInterval(() => this._dragScroll(), DRAG_SCROLL_INTERVAL);
 424   }
 425
 426   /**
 427    * Removes the listeners that are registered when mousedown is triggered.
 428    */
 429   private _removeMouseDownListeners(): void {
 430     this._rowContainer.ownerDocument.removeEventListener('mousemove', this._mouseMoveListener);
 431     this._rowContainer.ownerDocument.removeEventListener('mouseup', this._mouseUpListener);
 432     clearInterval(this._dragScrollIntervalTimer);
 433     this._dragScrollIntervalTimer = null;
 434   }
 435
 436   /**
 437    * Performs a shift click, setting the selection end position to the mouse
 438    * position.
 439    * @param event The mouse event.
 440    */
 441   private _onShiftClick(event: MouseEvent): void {
 442     if (this._model.selectionStart) {
 443       this._model.selectionEnd = this._getMouseBufferCoords(event);
 444     }
 445   }
 446
 447   /**
 448    * Performs a single click, resetting relevant state and setting the selection
 449    * start position.
 450    * @param event The mouse event.
 451    */
 452   private _onSingleClick(event: MouseEvent): void {
 453     this._model.selectionStartLength = 0;
 454     this._model.isSelectAllActive = false;
 455     this._activeSelectionMode = SelectionMode.NORMAL;
 456     this._model.selectionStart = this._getMouseBufferCoords(event);
 457     if (this._model.selectionStart) {
 458       this._model.selectionEnd = null;
 459       // If the mouse is over the second half of a wide character, adjust the
 460       // selection to cover the whole character
 461       const char = this._buffer.get(this._model.selectionStart[1])[this._model.selectionStart[0]];
 462       if (char[LINE_DATA_WIDTH_INDEX] === 0) {
 463         this._model.selectionStart[0]++;
 464       }
 465     }
 466   }
 467
 468   /**
 469    * Performs a double click, selecting the current work.
 470    * @param event The mouse event.
 471    */
 472   private _onDoubleClick(event: MouseEvent): void {
 473     const coords = this._getMouseBufferCoords(event);
 474     if (coords) {
 475       this._activeSelectionMode = SelectionMode.WORD;
 476       this._selectWordAt(coords);
 477     }
 478   }
 479
 480   /**
 481    * Performs a triple click, selecting the current line and activating line
 482    * select mode.
 483    * @param event The mouse event.
 484    */
 485   private _onTripleClick(event: MouseEvent): void {
 486     const coords = this._getMouseBufferCoords(event);
 487     if (coords) {
 488       this._activeSelectionMode = SelectionMode.LINE;
 489       this._selectLineAt(coords[1]);
 490     }
 491   }
 492
 493   /**
 494    * Sets the number of clicks for the current mousedown event based on the time
 495    * and position of the last mousedown event.
 496    * @param event The mouse event.
 497    */
 498   private _setMouseClickCount(event: MouseEvent): void {
 499     let currentTime = (new Date()).getTime();
 500     if (currentTime - this._lastMouseDownTime > CLEAR_MOUSE_DOWN_TIME || this._distanceFromLastMousePosition(event) > CLEAR_MOUSE_DISTANCE) {
 501       this._clickCount = 0;
 502     }
 503     this._lastMouseDownTime = currentTime;
 504     this._lastMousePosition = [event.pageX, event.pageY];
 505     this._clickCount++;
 506   }
 507
 508   /**
 509    * Gets the maximum number of pixels in each direction the mouse has moved.
 510    * @param event The mouse event.
 511    */
 512   private _distanceFromLastMousePosition(event: MouseEvent): number {
 513     const result = Math.max(
 514         Math.abs(this._lastMousePosition[0] - event.pageX),
 515         Math.abs(this._lastMousePosition[1] - event.pageY));
 516     return result;
 517   }
 518
 519   /**
 520    * Handles the mousemove event when the mouse button is down, recording the
 521    * end of the selection and refreshing the selection.
 522    * @param event The mousemove event.
 523    */
 524   private _onMouseMove(event: MouseEvent) {
 525     // Record the previous position so we know whether to redraw the selection
 526     // at the end.
 527     const previousSelectionEnd = this._model.selectionEnd ? [this._model.selectionEnd[0], this._model.selectionEnd[1]] : null;
 528
 529     // Set the initial selection end based on the mouse coordinates
 530     this._model.selectionEnd = this._getMouseBufferCoords(event);
 531
 532     // Select the entire line if line select mode is active.
 533     if (this._activeSelectionMode === SelectionMode.LINE) {
 534       if (this._model.selectionEnd[1] < this._model.selectionStart[1]) {
 535         this._model.selectionEnd[0] = 0;
 536       } else {
 537         this._model.selectionEnd[0] = this._terminal.cols;
 538       }
 539     } else if (this._activeSelectionMode === SelectionMode.WORD) {
 540       this._selectToWordAt(this._model.selectionEnd);
 541     }
 542
 543     // Determine the amount of scrolling that will happen.
 544     this._dragScrollAmount = this._getMouseEventScrollAmount(event);
 545
 546     // If the cursor was above or below the viewport, make sure it's at the
 547     // start or end of the viewport respectively.
 548     if (this._dragScrollAmount > 0) {
 549       this._model.selectionEnd[0] = this._terminal.cols - 1;
 550     } else if (this._dragScrollAmount < 0) {
 551       this._model.selectionEnd[0] = 0;
 552     }
 553
 554     // If the character is a wide character include the cell to the right in the
 555     // selection. Note that selections at the very end of the line will never
 556     // have a character.
 557     if (this._model.selectionEnd[1] < this._buffer.length) {
 558       const char = this._buffer.get(this._model.selectionEnd[1])[this._model.selectionEnd[0]];
 559       if (char && char[2] === 0) {
 560         this._model.selectionEnd[0]++;
 561       }
 562     }
 563
 564     // Only draw here if the selection changes.
 565     if (!previousSelectionEnd ||
 566         previousSelectionEnd[0] !== this._model.selectionEnd[0] ||
 567         previousSelectionEnd[1] !== this._model.selectionEnd[1]) {
 568       this.refresh(true);
 569     }
 570   }
 571
 572   /**
 573    * The callback that occurs every DRAG_SCROLL_INTERVAL ms that does the
 574    * scrolling of the viewport.
 575    */
 576   private _dragScroll() {
 577     if (this._dragScrollAmount) {
 578       this._terminal.scrollDisp(this._dragScrollAmount, false);
 579       // Re-evaluate selection
 580       if (this._dragScrollAmount > 0) {
 581         this._model.selectionEnd = [this._terminal.cols - 1, this._terminal.ydisp + this._terminal.rows];
 582       } else {
 583         this._model.selectionEnd = [0, this._terminal.ydisp];
 584       }
 585       this.refresh();
 586     }
 587   }
 588
 589   /**
 590    * Handles the mouseup event, removing the mousedown listeners.
 591    * @param event The mouseup event.
 592    */
 593   private _onMouseUp(event: MouseEvent) {
 594     this._removeMouseDownListeners();
 595   }
 596
 597   /**
 598    * Converts a viewport column to the character index on the buffer line, the
 599    * latter takes into account wide characters.
 600    * @param coords The coordinates to find the 2 index for.
 601    */
 602   private _convertViewportColToCharacterIndex(bufferLine: any, coords: [number, number]): number {
 603     let charIndex = coords[0];
 604     for (let i = 0; coords[0] >= i; i++) {
 605       const char = bufferLine[i];
 606       if (char[LINE_DATA_WIDTH_INDEX] === 0) {
 607         charIndex--;
 608       }
 609     }
 610     return charIndex;
 611   }
 612
 613   /**
 614    * Gets positional information for the word at the coordinated specified.
 615    * @param coords The coordinates to get the word at.
 616    */
 617   private _getWordAt(coords: [number, number]): IWordPosition {
 618     const bufferLine = this._buffer.get(coords[1]);
 619     const line = this._translateBufferLineToString(bufferLine, false);
 620
 621     // Get actual index, taking into consideration wide characters
 622     let endIndex = this._convertViewportColToCharacterIndex(bufferLine, coords);
 623     let startIndex = endIndex;
 624
 625     // Record offset to be used later
 626     const charOffset = coords[0] - startIndex;
 627     let leftWideCharCount = 0;
 628     let rightWideCharCount = 0;
 629
 630     if (line.charAt(startIndex) === ' ') {
 631       // Expand until non-whitespace is hit
 632       while (startIndex > 0 && line.charAt(startIndex - 1) === ' ') {
 633         startIndex--;
 634       }
 635       while (endIndex < line.length && line.charAt(endIndex + 1) === ' ') {
 636         endIndex++;
 637       }
 638     } else {
 639       // Expand until whitespace is hit. This algorithm works by scanning left
 640       // and right from the starting position, keeping both the index format
 641       // (line) and the column format (bufferLine) in sync. When a wide
 642       // character is hit, it is recorded and the column index is adjusted.
 643       let startCol = coords[0];
 644       let endCol = coords[0];
 645       // Consider the initial position, skip it and increment the wide char
 646       // variable
 647       if (bufferLine[startCol][LINE_DATA_WIDTH_INDEX] === 0) {
 648         leftWideCharCount++;
 649         startCol--;
 650       }
 651       if (bufferLine[endCol][LINE_DATA_WIDTH_INDEX] === 2) {
 652         rightWideCharCount++;
 653         endCol++;
 654       }
 655       // Expand the string in both directions until a space is hit
 656       while (startIndex > 0 && !this._isCharWordSeparator(line.charAt(startIndex - 1))) {
 657         if (bufferLine[startCol - 1][LINE_DATA_WIDTH_INDEX] === 0) {
 658           // If the next character is a wide char, record it and skip the column
 659           leftWideCharCount++;
 660           startCol--;
 661         }
 662         startIndex--;
 663         startCol--;
 664       }
 665       while (endIndex + 1 < line.length && !this._isCharWordSeparator(line.charAt(endIndex + 1))) {
 666         if (bufferLine[endCol + 1][LINE_DATA_WIDTH_INDEX] === 2) {
 667           // If the next character is a wide char, record it and skip the column
 668           rightWideCharCount++;
 669           endCol++;
 670         }
 671         endIndex++;
 672         endCol++;
 673       }
 674     }
 675
 676     const start = startIndex + charOffset - leftWideCharCount;
 677     const length = Math.min(endIndex - startIndex + leftWideCharCount + rightWideCharCount + 1/*include endIndex char*/, this._terminal.cols);
 678     return {start, length};
 679   }
 680
 681   /**
 682    * Selects the word at the coordinates specified.
 683    * @param coords The coordinates to get the word at.
 684    */
 685   protected _selectWordAt(coords: [number, number]): void {
 686     const wordPosition = this._getWordAt(coords);
 687     this._model.selectionStart = [wordPosition.start, coords[1]];
 688     this._model.selectionStartLength = wordPosition.length;
 689   }
 690
 691   /**
 692    * Sets the selection end to the word at the coordinated specified.
 693    * @param coords The coordinates to get the word at.
 694    */
 695   private _selectToWordAt(coords: [number, number]): void {
 696     const wordPosition = this._getWordAt(coords);
 697     this._model.selectionEnd = [this._model.areSelectionValuesReversed() ? wordPosition.start : (wordPosition.start + wordPosition.length), coords[1]];
 698   }
 699
 700   /**
 701    * Gets whether the character is considered a word separator by the select
 702    * word logic.
 703    * @param char The character to check.
 704    */
 705   private _isCharWordSeparator(char: string): boolean {
 706     return WORD_SEPARATORS.indexOf(char) >= 0;
 707   }
 708
 709   /**
 710    * Selects the line specified.
 711    * @param line The line index.
 712    */
 713   protected _selectLineAt(line: number): void {
 714     this._model.selectionStart = [0, line];
 715     this._model.selectionStartLength = this._terminal.cols;
 716   }
 717 }