Convert xterm.js to TypeScript

src/Buffer.test.ts

@@ -1,31 +1,148 @@
 /**
  * @license MIT
  */
+
 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.options.scrollback = 1000;
     buffer = new Buffer(terminal);
   });
 
   describe('constructor', () => {
     it('should create a CircularList with max length equal to scrollback, for its lines', () => {
       assert.instanceOf(buffer.lines, CircularList);
-      assert.equal(buffer.lines.maxLength, terminal.scrollback);
+      assert.equal(buffer.lines.maxLength, terminal.options.scrollback);
     });
     it('should set the Buffer\'s scrollBottom value equal to the terminal\'s rows -1', () => {
       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

@@ -2,8 +2,9 @@
  * @license MIT
  */
 
-import { ITerminal } from './Interfaces';
+import { ITerminal, IBuffer } from './Interfaces';
 import { CircularList } from './utils/CircularList';
+import { LineData, CharData } from './Types';
 
 /**
  * This class represents a terminal buffer (an internal state of the terminal), where the
@@ -12,31 +13,126 @@ 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<LineData>;
 
+  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<LineData> {
+    return this._lines;
+  }
+
+  public fillViewportRows(): void {
+    if (this._lines.length === 0) {
+      let i = this._terminal.rows;
+      while (i--) {
+        this.lines.push(this._terminal.blankLine());
+      }
+    }
+  }
+
+  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<LineData>(this._terminal.options.scrollback);
+    this.scrollBottom = this._terminal.rows - 1;
+  }
+
+  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: CharData = [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

@@ -1,21 +1,22 @@
 /**
  * @license MIT
  */
+
 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.options.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 +68,16 @@ 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);
   }
+
+  public resize(newCols: number, newRows: number): void {
+    this._normal.resize(newCols, newRows);
+    this._alt.resize(newCols, newRows);
+  }
 }

src/Charsets.ts

@@ -2,17 +2,19 @@
  * @license MIT
  */
 
+import { Charset } from './Types';
+
 /**
  * The character sets supported by the terminal. These enable several languages
  * to be represented within the terminal with only 8-bit encoding. See ISO 2022
  * for a discussion on character sets. Only VT100 character sets are supported.
  */
-export const CHARSETS: {[key: string]: {[key: string]: string}} = {};
+export const CHARSETS: { [key: string]: Charset } = {};
 
 /**
  * The default character set, US.
  */
-export const DEFAULT_CHARSET = CHARSETS['B'];
+export const DEFAULT_CHARSET: Charset = CHARSETS['B'];
 
 /**
  * DEC Special Character and Line Drawing Set.