Add lint rule to ensure on prefix is only for event emitters

Fixes #4183

.eslintrc.json

@@ -96,7 +96,11 @@
       { "selector": "enumMember", "format": ["UPPER_CASE"] },
       // memberLike - Allow enum-like objects to use UPPER_CASE
       { "selector": "property", "modifiers": ["public"], "format": ["camelCase", "UPPER_CASE"] },
-      { "selector": "method", "modifiers": ["public"], "format": ["camelCase", "UPPER_CASE"] },
+      // restrict on* naming for events only
+      { "selector": "method", "modifiers": ["public"], "format": ["camelCase", "UPPER_CASE"], "custom": {
+        "regex": "^on[A-Z].+",
+        "match": false
+      } },
       // typeLike
       { "selector": "typeLike", "format": ["PascalCase"] },
       { "selector": "interface", "format": ["PascalCase"], "prefix": ["I"] }

addons/xterm-addon-canvas/src/BaseRenderLayer.ts

@@ -75,13 +75,13 @@ export abstract class BaseRenderLayer extends Disposable implements IRenderLayer
     }
   }
 
-  public onOptionsChanged(): void {}
-  public onBlur(): void {}
-  public onFocus(): void {}
-  public onCursorMove(): void {}
-  public onGridChanged(startRow: number, endRow: number): void {}
+  public handleOptionsChanged(): void {}
+  public handleBlur(): void {}
+  public handleFocus(): void {}
+  public handleCursorMove(): void {}
+  public handleGridChanged(startRow: number, endRow: number): void {}
 
-  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
+  public handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
     this._selectionModel.update(this._terminal, start, end, columnSelectMode);
   }
 
@@ -105,7 +105,7 @@ export abstract class BaseRenderLayer extends Disposable implements IRenderLayer
 
     // Regenerate char atlas and force a full redraw
     this._refreshCharAtlas(this._colors);
-    this.onGridChanged(0, this._bufferService.rows - 1);
+    this.handleGridChanged(0, this._bufferService.rows - 1);
   }
 
   /**

addons/xterm-addon-canvas/src/CanvasAddon.ts

@@ -45,11 +45,11 @@ export class CanvasAddon extends Disposable implements ITerminalAddon {
     this._renderer = new CanvasRenderer(terminal, colors, screenElement, linkifier, bufferService, charSizeService, optionsService, characterJoinerService, coreService, coreBrowserService, decorationService);
     this.register(forwardEvent(this._renderer.onChangeTextureAtlas, this._onChangeTextureAtlas));
     renderService.setRenderer(this._renderer);
-    renderService.onResize(bufferService.cols, bufferService.rows);
+    renderService.handleResize(bufferService.cols, bufferService.rows);
 
     this.register(toDisposable(() => {
       renderService.setRenderer((this._terminal as any)._core._createRenderer());
-      renderService.onResize(terminal.cols, terminal.rows);
+      renderService.handleResize(terminal.cols, terminal.rows);
       this._renderer?.dispose();
       this._renderer = undefined;
     }));

addons/xterm-addon-canvas/src/CanvasRenderer.ts

@@ -69,7 +69,7 @@ export class CanvasRenderer extends Disposable implements IRenderer {
 
     this.register(observeDevicePixelDimensions(this._renderLayers[0].canvas, this._coreBrowserService.window, (w, h) => this._setCanvasDevicePixelDimensions(w, h)));
 
-    this.onOptionsChanged();
+    this.handleOptionsChanged();
 
     this.register(toDisposable(() => {
       for (const l of this._renderLayers) {
@@ -83,12 +83,12 @@ export class CanvasRenderer extends Disposable implements IRenderer {
     return this._renderLayers[0].cacheCanvas;
   }
 
-  public onDevicePixelRatioChange(): void {
+  public handleDevicePixelRatioChange(): void {
     // If the device pixel ratio changed, the char atlas needs to be regenerated
     // and the terminal needs to refreshed
     if (this._devicePixelRatio !== this._coreBrowserService.dpr) {
       this._devicePixelRatio = this._coreBrowserService.dpr;
-      this.onResize(this._bufferService.cols, this._bufferService.rows);
+      this.handleResize(this._bufferService.cols, this._bufferService.rows);
     }
   }
 
@@ -101,7 +101,7 @@ export class CanvasRenderer extends Disposable implements IRenderer {
     }
   }
 
-  public onResize(cols: number, rows: number): void {
+  public handleResize(cols: number, rows: number): void {
     // Update character and canvas dimensions
     this._updateDimensions();
 
@@ -115,32 +115,32 @@ export class CanvasRenderer extends Disposable implements IRenderer {
     this._screenElement.style.height = `${this.dimensions.canvasHeight}px`;
   }
 
-  public onCharSizeChanged(): void {
-    this.onResize(this._bufferService.cols, this._bufferService.rows);
+  public handleCharSizeChanged(): void {
+    this.handleResize(this._bufferService.cols, this._bufferService.rows);
   }
 
-  public onBlur(): void {
-    this._runOperation(l => l.onBlur());
+  public handleBlur(): void {
+    this._runOperation(l => l.handleBlur());
   }
 
-  public onFocus(): void {
-    this._runOperation(l => l.onFocus());
+  public handleFocus(): void {
+    this._runOperation(l => l.handleFocus());
   }
 
-  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
-    this._runOperation(l => l.onSelectionChanged(start, end, columnSelectMode));
+  public handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {
+    this._runOperation(l => l.handleSelectionChanged(start, end, columnSelectMode));
     // Selection foreground requires a full re-render
     if (this._colors.selectionForeground) {
       this._onRequestRedraw.fire({ start: 0, end: this._bufferService.rows - 1 });
     }
   }
 
-  public onCursorMove(): void {
-    this._runOperation(l => l.onCursorMove());
+  public handleCursorMove(): void {
+    this._runOperation(l => l.handleCursorMove());
   }
 
-  public onOptionsChanged(): void {
-    this._runOperation(l => l.onOptionsChanged());
+  public handleOptionsChanged(): void {
+    this._runOperation(l => l.handleOptionsChanged());
   }
 
   public clear(): void {
@@ -159,7 +159,7 @@ export class CanvasRenderer extends Disposable implements IRenderer {
    */
   public renderRows(start: number, end: number): void {
     for (const l of this._renderLayers) {
-      l.onGridChanged(start, end);
+      l.handleGridChanged(start, end);
     }
   }
 

addons/xterm-addon-canvas/src/CursorRenderLayer.ts

@@ -79,20 +79,20 @@ export class CursorRenderLayer extends BaseRenderLayer {
   public reset(): void {
     this._clearCursor();
     this._cursorBlinkStateManager?.restartBlinkAnimation();
-    this.onOptionsChanged();
+    this.handleOptionsChanged();
   }
 
-  public onBlur(): void {
+  public handleBlur(): void {
     this._cursorBlinkStateManager?.pause();
     this._onRequestRedraw.fire({ start: this._bufferService.buffer.y, end: this._bufferService.buffer.y });
   }
 
-  public onFocus(): void {
+  public handleFocus(): void {
     this._cursorBlinkStateManager?.resume();
     this._onRequestRedraw.fire({ start: this._bufferService.buffer.y, end: this._bufferService.buffer.y });
   }
 
-  public onOptionsChanged(): void {
+  public handleOptionsChanged(): void {
     if (this._optionsService.rawOptions.cursorBlink) {
       if (!this._cursorBlinkStateManager) {
         this._cursorBlinkStateManager = new CursorBlinkStateManager(this._coreBrowserService.isFocused, () => {
@@ -108,11 +108,11 @@ export class CursorRenderLayer extends BaseRenderLayer {
     this._onRequestRedraw.fire({ start: this._bufferService.buffer.y, end: this._bufferService.buffer.y });
   }
 
-  public onCursorMove(): void {
+  public handleCursorMove(): void {
     this._cursorBlinkStateManager?.restartBlinkAnimation();
   }
 
-  public onGridChanged(startRow: number, endRow: number): void {
+  public handleGridChanged(startRow: number, endRow: number): void {
     if (!this._cursorBlinkStateManager || this._cursorBlinkStateManager.isPaused) {
       this._render(false);
     } else {

addons/xterm-addon-canvas/src/SelectionRenderLayer.ts

@@ -59,18 +59,18 @@ export class SelectionRenderLayer extends BaseRenderLayer {
     }
   }
 
-  public onBlur(): void {
+  public handleBlur(): void {
     this.reset();
     this._redrawSelection(this._selectionModel.selectionStart, this._selectionModel.selectionEnd, this._selectionModel.columnSelectMode);
   }
 
-  public onFocus(): void {
+  public handleFocus(): void {
     this.reset();
     this._redrawSelection(this._selectionModel.selectionStart, this._selectionModel.selectionEnd, this._selectionModel.columnSelectMode);
   }
 
-  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
-    super.onSelectionChanged(start, end, columnSelectMode);
+  public handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
+    super.handleSelectionChanged(start, end, columnSelectMode);
     this._redrawSelection(start, end, columnSelectMode);
   }
 

addons/xterm-addon-canvas/src/TextRenderLayer.ts

@@ -236,7 +236,7 @@ export class TextRenderLayer extends BaseRenderLayer {
     this._forEachCell(firstRow, lastRow, (cell, x, y) => this._drawChars(cell, x, y));
   }
 
-  public onGridChanged(firstRow: number, lastRow: number): void {
+  public handleGridChanged(firstRow: number, lastRow: number): void {
     // Resize has not been called yet
     if (this._state.cache.length === 0) {
       return;
@@ -251,7 +251,7 @@ export class TextRenderLayer extends BaseRenderLayer {
     this._drawForeground(firstRow, lastRow);
   }
 
-  public onOptionsChanged(): void {
+  public handleOptionsChanged(): void {
     this._setTransparency(this._optionsService.rawOptions.allowTransparency);
   }
 

addons/xterm-addon-canvas/src/Types.d.ts

@@ -42,14 +42,14 @@ export interface IRenderer extends IDisposable {
   readonly onRequestRedraw: IEvent<IRequestRedrawEvent>;
 
   setColors(colors: IColorSet): void;
-  onDevicePixelRatioChange(): void;
-  onResize(cols: number, rows: number): void;
-  onCharSizeChanged(): void;
-  onBlur(): void;
-  onFocus(): void;
-  onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
-  onCursorMove(): void;
-  onOptionsChanged(): void;
+  handleDevicePixelRatioChange(): void;
+  handleResize(cols: number, rows: number): void;
+  handleCharSizeChanged(): void;
+  handleBlur(): void;
+  handleFocus(): void;
+  handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
+  handleCursorMove(): void;
+  handleOptionsChanged(): void;
   clear(): void;
   renderRows(start: number, end: number): void;
   clearTextureAtlas?(): void;
@@ -62,22 +62,22 @@ export interface IRenderLayer extends IDisposable {
   /**
    * Called when the terminal loses focus.
    */
-  onBlur(): void;
+  handleBlur(): void;
 
   /**
    * * Called when the terminal gets focus.
    */
-  onFocus(): void;
+  handleFocus(): void;
 
   /**
    * Called when the cursor is moved.
    */
-  onCursorMove(): void;
+  handleCursorMove(): void;
 
   /**
    * Called when options change.
    */
-  onOptionsChanged(): void;
+  handleOptionsChanged(): void;
 
   /**
    * Called when the theme changes.
@@ -88,12 +88,12 @@ export interface IRenderLayer extends IDisposable {
    * Called when the data in the grid has changed (or needs to be rendered
    * again).
    */
-  onGridChanged(startRow: number, endRow: number): void;
+  handleGridChanged(startRow: number, endRow: number): void;
 
   /**
    * Calls when the selection changes.
    */
-  onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
+  handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
 
   /**
    * Resize the render layer.

addons/xterm-addon-webgl/src/GlyphRenderer.ts

@@ -167,7 +167,7 @@ export class GlyphRenderer extends Disposable {
     gl.blendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA);
 
     // Set viewport
-    this.onResize();
+    this.handleResize();
   }
 
   public beginFrame(): boolean {
@@ -263,7 +263,7 @@ export class GlyphRenderer extends Disposable {
     }
   }
 
-  public onResize(): void {
+  public handleResize(): void {
     const gl = this._gl;
     gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
     this.clear();

addons/xterm-addon-webgl/src/RectangleRenderer.ts

@@ -151,7 +151,7 @@ export class RectangleRenderer extends Disposable {
     gl.drawElementsInstanced(this._gl.TRIANGLES, 6, gl.UNSIGNED_BYTE, 0, this._vertices.count);
   }
 
-  public onResize(): void {
+  public handleResize(): void {
     this._updateViewportRectangle();
   }
 

addons/xterm-addon-webgl/src/WebglAddon.ts

@@ -51,7 +51,7 @@ export class WebglAddon extends Disposable implements ITerminalAddon {
     this.register(toDisposable(() => {
       const renderService: IRenderService = (this._terminal as any)._core._renderService;
       renderService.setRenderer((this._terminal as any)._core._createRenderer());
-      renderService.onResize(terminal.cols, terminal.rows);
+      renderService.handleResize(terminal.cols, terminal.rows);
     }));
   }
 

addons/xterm-addon-webgl/src/WebglRenderer.ts

@@ -162,16 +162,16 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._clearModel(true);
   }
 
-  public onDevicePixelRatioChange(): void {
+  public handleDevicePixelRatioChange(): void {
     // If the device pixel ratio changed, the char atlas needs to be regenerated
     // and the terminal needs to refreshed
     if (this._devicePixelRatio !== this._coreBrowserService.dpr) {
       this._devicePixelRatio = this._coreBrowserService.dpr;
-      this.onResize(this._terminal.cols, this._terminal.rows);
+      this.handleResize(this._terminal.cols, this._terminal.rows);
     }
   }
 
-  public onResize(cols: number, rows: number): void {
+  public handleResize(cols: number, rows: number): void {
     // Update character and canvas dimensions
     this._updateDimensions();
 
@@ -193,9 +193,9 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._core.screenElement!.style.height = `${this.dimensions.canvasHeight}px`;
 
     this._rectangleRenderer.setDimensions(this.dimensions);
-    this._rectangleRenderer.onResize();
+    this._rectangleRenderer.handleResize();
     this._glyphRenderer.setDimensions(this.dimensions);
-    this._glyphRenderer.onResize();
+    this._glyphRenderer.handleResize();
 
     this._refreshCharAtlas();
 
@@ -204,43 +204,43 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._clearModel(false);
   }
 
-  public onCharSizeChanged(): void {
-    this.onResize(this._terminal.cols, this._terminal.rows);
+  public handleCharSizeChanged(): void {
+    this.handleResize(this._terminal.cols, this._terminal.rows);
   }
 
-  public onBlur(): void {
+  public handleBlur(): void {
     for (const l of this._renderLayers) {
-      l.onBlur(this._terminal);
+      l.handleBlur(this._terminal);
     }
     // Request a redraw for active/inactive selection background
     this._requestRedrawViewport();
   }
 
-  public onFocus(): void {
+  public handleFocus(): void {
     for (const l of this._renderLayers) {
-      l.onFocus(this._terminal);
+      l.handleFocus(this._terminal);
     }
     // Request a redraw for active/inactive selection background
     this._requestRedrawViewport();
   }
 
-  public onSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
+  public handleSelectionChanged(start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void {
     for (const l of this._renderLayers) {
-      l.onSelectionChanged(this._terminal, start, end, columnSelectMode);
+      l.handleSelectionChanged(this._terminal, start, end, columnSelectMode);
     }
     this._model.selection.update(this._terminal, start, end, columnSelectMode);
     this._requestRedrawViewport();
   }
 
-  public onCursorMove(): void {
+  public handleCursorMove(): void {
     for (const l of this._renderLayers) {
-      l.onCursorMove(this._terminal);
+      l.handleCursorMove(this._terminal);
     }
   }
 
-  public onOptionsChanged(): void {
+  public handleOptionsChanged(): void {
     for (const l of this._renderLayers) {
-      l.onOptionsChanged(this._terminal);
+      l.handleOptionsChanged(this._terminal);
     }
     this._updateDimensions();
     this._refreshCharAtlas();
@@ -258,7 +258,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
     this._glyphRenderer = this.register(new GlyphRenderer(this._terminal, this._gl, this.dimensions));
 
     // Update dimensions and acquire char atlas
-    this.onCharSizeChanged();
+    this.handleCharSizeChanged();
   }
 
   /**
@@ -328,7 +328,7 @@ export class WebglRenderer extends Disposable implements IRenderer {
 
     // Update render layers
     for (const l of this._renderLayers) {
-      l.onGridChanged(this._terminal, start, end);
+      l.handleGridChanged(this._terminal, start, end);
     }
 
     // Tell renderer the frame is beginning

addons/xterm-addon-webgl/src/renderLayer/BaseRenderLayer.ts

@@ -54,12 +54,12 @@ export abstract class BaseRenderLayer extends Disposable implements IRenderLayer
     }
   }
 
-  public onOptionsChanged(terminal: Terminal): void {}
-  public onBlur(terminal: Terminal): void {}
-  public onFocus(terminal: Terminal): void {}
-  public onCursorMove(terminal: Terminal): void {}
-  public onGridChanged(terminal: Terminal, startRow: number, endRow: number): void {}
-  public onSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {}
+  public handleOptionsChanged(terminal: Terminal): void {}
+  public handleBlur(terminal: Terminal): void {}
+  public handleFocus(terminal: Terminal): void {}
+  public handleCursorMove(terminal: Terminal): void {}
+  public handleGridChanged(terminal: Terminal, startRow: number, endRow: number): void {}
+  public handleSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean = false): void {}
 
   public setColors(terminal: Terminal, colorSet: IColorSet): void {
     this._refreshCharAtlas(terminal, colorSet);
@@ -81,7 +81,7 @@ export abstract class BaseRenderLayer extends Disposable implements IRenderLayer
 
     // Regenerate char atlas and force a full redraw
     this._refreshCharAtlas(terminal, this._colors);
-    this.onGridChanged(terminal, 0, terminal.rows - 1);
+    this.handleGridChanged(terminal, 0, terminal.rows - 1);
   }
 
   /**

addons/xterm-addon-webgl/src/renderLayer/CursorRenderLayer.ts

@@ -55,7 +55,7 @@ export class CursorRenderLayer extends BaseRenderLayer {
       'block': this._renderBlockCursor.bind(this),
       'underline': this._renderUnderlineCursor.bind(this)
     };
-    this.onOptionsChanged(terminal);
+    this.handleOptionsChanged(terminal);
     this.register(toDisposable(() => {
       this._cursorBlinkStateManager?.dispose();
       this._cursorBlinkStateManager = undefined;
@@ -77,20 +77,20 @@ export class CursorRenderLayer extends BaseRenderLayer {
   public reset(terminal: Terminal): void {
     this._clearCursor();
     this._cursorBlinkStateManager?.restartBlinkAnimation(terminal);
-    this.onOptionsChanged(terminal);
+    this.handleOptionsChanged(terminal);
   }
 
-  public onBlur(terminal: Terminal): void {
+  public handleBlur(terminal: Terminal): void {
     this._cursorBlinkStateManager?.pause();
     this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
   }
 
-  public onFocus(terminal: Terminal): void {
+  public handleFocus(terminal: Terminal): void {
     this._cursorBlinkStateManager?.resume(terminal);
     this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
   }
 
-  public onOptionsChanged(terminal: Terminal): void {
+  public handleOptionsChanged(terminal: Terminal): void {
     if (terminal.options.cursorBlink) {
       if (!this._cursorBlinkStateManager) {
         this._cursorBlinkStateManager = new CursorBlinkStateManager(() => {
@@ -106,11 +106,11 @@ export class CursorRenderLayer extends BaseRenderLayer {
     this._onRequestRefreshRowsEvent.fire({ start: terminal.buffer.active.cursorY, end: terminal.buffer.active.cursorY });
   }
 
-  public onCursorMove(terminal: Terminal): void {
+  public handleCursorMove(terminal: Terminal): void {
     this._cursorBlinkStateManager?.restartBlinkAnimation(terminal);
   }
 
-  public onGridChanged(terminal: Terminal, startRow: number, endRow: number): void {
+  public handleGridChanged(terminal: Terminal, startRow: number, endRow: number): void {
     if (!this._cursorBlinkStateManager || this._cursorBlinkStateManager.isPaused) {
       this._render(terminal, false);
     } else {

addons/xterm-addon-webgl/src/renderLayer/Types.ts

@@ -11,22 +11,22 @@ export interface IRenderLayer extends IDisposable {
   /**
    * Called when the terminal loses focus.
    */
-  onBlur(terminal: Terminal): void;
+  handleBlur(terminal: Terminal): void;
 
   /**
    * * Called when the terminal gets focus.
    */
-  onFocus(terminal: Terminal): void;
+  handleFocus(terminal: Terminal): void;
 
   /**
    * Called when the cursor is moved.
    */
-  onCursorMove(terminal: Terminal): void;
+  handleCursorMove(terminal: Terminal): void;
 
   /**
    * Called when options change.
    */
-  onOptionsChanged(terminal: Terminal): void;
+  handleOptionsChanged(terminal: Terminal): void;
 
   /**
    * Called when the theme changes.
@@ -37,12 +37,12 @@ export interface IRenderLayer extends IDisposable {
    * Called when the data in the grid has changed (or needs to be rendered
    * again).
    */
-  onGridChanged(terminal: Terminal, startRow: number, endRow: number): void;
+  handleGridChanged(terminal: Terminal, startRow: number, endRow: number): void;
 
   /**
    * Calls when the selection changes.
    */
-  onSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
+  handleSelectionChanged(terminal: Terminal, start: [number, number] | undefined, end: [number, number] | undefined, columnSelectMode: boolean): void;
 
   /**
    * Registers a handler to join characters to render as a group

src/browser/ColorManager.ts

@@ -102,7 +102,7 @@ export class ColorManager implements IColorManager {
     this._updateRestoreColors();
   }
 
-  public onOptionsChange(key: string, value: any): void {
+  public handleOptionsChange(key: string, value: any): void {
     switch (key) {
       case 'minimumContrastRatio':
         this._contrastCache.clear();

src/browser/Terminal.ts

@@ -238,7 +238,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
       }
     }
     this._renderService?.setColors(this._colorManager.colors);
-    this.viewport?.onThemeChange(this._colorManager.colors);
+    this.viewport?.handleThemeChange(this._colorManager.colors);
   }
 
   protected _setup(): void {
@@ -289,7 +289,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
         // When the font changes the size of the cells may change which requires a renderer clear
         if (this._renderService) {
           this._renderService.clear();
-          this._renderService.onResize(this.cols, this.rows);
+          this._renderService.handleResize(this.cols, this.rows);
           this.refresh(0, this.rows - 1);
         }
         break;
@@ -500,7 +500,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
 
     this._theme = this.options.theme || this._theme;
     this._colorManager = new ColorManager();
-    this.register(this.optionsService.onOptionChange(e => this._colorManager!.onOptionsChange(e, this.optionsService.rawOptions[e])));
+    this.register(this.optionsService.onOptionChange(e => this._colorManager!.handleOptionsChange(e, this.optionsService.rawOptions[e])));
     this._colorManager.setTheme(this._theme);
 
     this._characterJoinerService = this._instantiationService.createInstance(CharacterJoinerService);
@@ -533,17 +533,17 @@ export class Terminal extends CoreTerminal implements ITerminal {
       this._viewportScrollArea,
       this.element
     );
-    this.viewport.onThemeChange(this._colorManager.colors);
+    this.viewport.handleThemeChange(this._colorManager.colors);
     this.register(this._inputHandler.onRequestSyncScrollBar(() => this.viewport!.syncScrollArea()));
     this.register(this.viewport);
 
     this.register(this.onCursorMove(() => {
-      this._renderService!.onCursorMove();
+      this._renderService!.handleCursorMove();
       this._syncTextArea();
     }));
-    this.register(this.onResize(() => this._renderService!.onResize(this.cols, this.rows)));
-    this.register(this.onBlur(() => this._renderService!.onBlur()));
-    this.register(this.onFocus(() => this._renderService!.onFocus()));
+    this.register(this.onResize(() => this._renderService!.handleResize(this.cols, this.rows)));
+    this.register(this.onBlur(() => this._renderService!.handleBlur()));
+    this.register(this.onFocus(() => this._renderService!.handleFocus()));
     this.register(this._renderService.onDimensionsChange(() => this.viewport!.syncScrollArea()));
 
     this._selectionService = this.register(this._instantiationService.createInstance(SelectionService,
@@ -554,7 +554,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
     this._instantiationService.setService(ISelectionService, this._selectionService);
     this.register(this._selectionService.onRequestScrollLines(e => this.scrollLines(e.amount, e.suppressScrollEvent)));
     this.register(this._selectionService.onSelectionChange(() => this._onSelectionChange.fire()));
-    this.register(this._selectionService.onRequestRedraw(e => this._renderService!.onSelectionChanged(e.start, e.end, e.columnSelectMode)));
+    this.register(this._selectionService.onRequestRedraw(e => this._renderService!.handleSelectionChanged(e.start, e.end, e.columnSelectMode)));
     this.register(this._selectionService.onLinuxMouseSelection(text => {
       // If there's a new selection, put it into the textarea, focus and select it
       // in order to register it as a selection on the OS. This event is fired
@@ -571,7 +571,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
 
     this.linkifier2.attachToDom(this.screenElement, this._mouseService, this._renderService);
     this.register(this._instantiationService.createInstance(BufferDecorationRenderer, this.screenElement));
-    this.register(addDisposableDomListener(this.element, 'mousedown', (e: MouseEvent) => this._selectionService!.onMouseDown(e)));
+    this.register(addDisposableDomListener(this.element, 'mousedown', (e: MouseEvent) => this._selectionService!.handleMouseDown(e)));
 
     // apply mouse event classes set by escape codes before terminal was attached
     if (this.coreMouseService.areMouseEventsActive) {
@@ -621,7 +621,7 @@ export class Terminal extends CoreTerminal implements ITerminal {
     this._theme = theme;
     this._colorManager?.setTheme(theme);
     this._renderService?.setColors(this._colorManager!.colors);
-    this.viewport?.onThemeChange(this._colorManager!.colors);
+    this.viewport?.handleThemeChange(this._colorManager!.colors);
   }
 
   /**
@@ -860,20 +860,20 @@ export class Terminal extends CoreTerminal implements ITerminal {
 
       // normal viewport scrolling
       // conditionally stop event, if the viewport still had rows to scroll within
-      if (this.viewport!.onWheel(ev)) {
+      if (this.viewport!.handleWheel(ev)) {
         return this.cancel(ev);
       }
     }, { passive: false }));
 
     this.register(addDisposableDomListener(el, 'touchstart', (ev: TouchEvent) => {
       if (this.coreMouseService.areMouseEventsActive) return;
-      this.viewport!.onTouchStart(ev);
+      this.viewport!.handleTouchStart(ev);
       return this.cancel(ev);
     }, { passive: true }));
 
     this.register(addDisposableDomListener(el, 'touchmove', (ev: TouchEvent) => {
       if (this.coreMouseService.areMouseEventsActive) return;
-      if (!this.viewport!.onTouchMove(ev)) {
+      if (!this.viewport!.handleTouchMove(ev)) {
         return this.cancel(ev);
       }
     }, { passive: false }));

src/browser/TestUtils.test.ts

@@ -285,14 +285,14 @@ export class MockRenderer implements IRenderer {
   public registerDecoration(decorationOptions: IDecorationOptions): IDecoration {
     throw new Error('Method not implemented.');
   }
-  public onResize(cols: number, rows: number): void { }
-  public onCharSizeChanged(): void { }
-  public onBlur(): void { }
-  public onFocus(): void { }
-  public onSelectionChanged(start: [number, number], end: [number, number]): void { }
-  public onCursorMove(): void { }
-  public onOptionsChanged(): void { }
-  public onDevicePixelRatioChange(): void { }
+  public handleResize(cols: number, rows: number): void { }
+  public handleCharSizeChanged(): void { }
+  public handleBlur(): void { }
+  public handleFocus(): void { }
+  public handleSelectionChanged(start: [number, number], end: [number, number]): void { }
+  public handleCursorMove(): void { }
+  public handleOptionsChanged(): void { }
+  public handleDevicePixelRatioChange(): void { }
   public clear(): void { }
   public renderRows(start: number, end: number): void { }
 }
@@ -302,16 +302,16 @@ export class MockViewport implements IViewport {
     throw new Error('Method not implemented.');
   }
   public scrollBarWidth: number = 0;
-  public onThemeChange(colors: IColorSet): void {
+  public handleThemeChange(colors: IColorSet): void {
     throw new Error('Method not implemented.');
   }
-  public onWheel(ev: WheelEvent): boolean {
+  public handleWheel(ev: WheelEvent): boolean {
     throw new Error('Method not implemented.');
   }
-  public onTouchStart(ev: TouchEvent): void {
+  public handleTouchStart(ev: TouchEvent): void {
     throw new Error('Method not implemented.');
   }
-  public onTouchMove(ev: TouchEvent): boolean {
+  public handleTouchMove(ev: TouchEvent): boolean {
     throw new Error('Method not implemented.');
   }
   public syncScrollArea(): void { }
@@ -410,25 +410,25 @@ export class MockRenderService implements IRenderService {
   public setColors(colors: IColorSet): void {
     throw new Error('Method not implemented.');
   }
-  public onDevicePixelRatioChange(): void {
+  public handleDevicePixelRatioChange(): void {
     throw new Error('Method not implemented.');
   }
-  public onResize(cols: number, rows: number): void {
+  public handleResize(cols: number, rows: number): void {
     throw new Error('Method not implemented.');
   }
-  public onCharSizeChanged(): void {
+  public handleCharSizeChanged(): void {
     throw new Error('Method not implemented.');
   }
-  public onBlur(): void {
+  public handleBlur(): void {
     throw new Error('Method not implemented.');
   }
-  public onFocus(): void {
+  public handleFocus(): void {
     throw new Error('Method not implemented.');
   }
-  public onSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
+  public handleSelectionChanged(start: [number, number], end: [number, number], columnSelectMode: boolean): void {
     throw new Error('Method not implemented.');
   }
-  public onCursorMove(): void {
+  public handleCursorMove(): void {
     throw new Error('Method not implemented.');
   }
   public clear(): void {
@@ -498,7 +498,7 @@ export class MockSelectionService implements ISelectionService {
   public refresh(isLinuxMouseSelection?: boolean): void {
     throw new Error('Method not implemented.');
   }
-  public onMouseDown(event: MouseEvent): void {
+  public handleMouseDown(event: MouseEvent): void {
     throw new Error('Method not implemented.');
   }
   public isCellInSelection(x: number, y: number): boolean {

src/browser/Types.d.ts

@@ -108,7 +108,7 @@ export interface IBrowser {
 
 export interface IColorManager {
   colors: IColorSet;
-  onOptionsChange(key: string, value: any): void;
+  handleOptionsChange(key: string, value: any): void;
 }
 
 export interface IColorSet {
@@ -147,10 +147,10 @@ export interface IViewport extends IDisposable {
   scrollBarWidth: number;
   syncScrollArea(immediate?: boolean): void;
   getLinesScrolled(ev: WheelEvent): number;
-  onWheel(ev: WheelEvent): boolean;
-  onTouchStart(ev: TouchEvent): void;
-  onTouchMove(ev: TouchEvent): boolean;
-  onThemeChange(colors: IColorSet): void;
+  handleWheel(ev: WheelEvent): boolean;
+  handleTouchStart(ev: TouchEvent): void;
+  handleTouchMove(ev: TouchEvent): boolean;
+  handleThemeChange(colors: IColorSet): void;
 }
 
 export interface ILinkifierEvent {

src/browser/Viewport.ts

@@ -77,7 +77,7 @@ export class Viewport extends Disposable implements IViewport {
     setTimeout(() => this.syncScrollArea(), 0);
   }
 
-  public onThemeChange(colors: IColorSet): void {
+  public handleThemeChange(colors: IColorSet): void {
     this._viewportElement.style.backgroundColor = colors.background.css;
   }
 
@@ -234,7 +234,7 @@ export class Viewport extends Disposable implements IViewport {
    * `Viewport`.
    * @param ev The mouse wheel event.
    */
-  public onWheel(ev: WheelEvent): boolean {
+  public handleWheel(ev: WheelEvent): boolean {
     const amount = this._getPixelsScrolled(ev);
     if (amount === 0) {
       return false;
@@ -315,7 +315,7 @@ export class Viewport extends Disposable implements IViewport {
    * Handles the touchstart event, recording the touch occurred.
    * @param ev The touch event.
    */
-  public onTouchStart(ev: TouchEvent): void {
+  public handleTouchStart(ev: TouchEvent): void {
     this._lastTouchY = ev.touches[0].pageY;
   }
 
@@ -323,7 +323,7 @@ export class Viewport extends Disposable implements IViewport {
    * Handles the touchmove event, scrolling the viewport if the position shifted.
    * @param ev The touch event.
    */
-  public onTouchMove(ev: TouchEvent): boolean {
+  public handleTouchMove(ev: TouchEvent): boolean {
     const deltaY = this._lastTouchY - ev.touches[0].pageY;
     this._lastTouchY = ev.touches[0].pageY;
     if (deltaY === 0) {