Fix linting issues

Co-authored-by: Tyriar <2193314+Tyriar@users.noreply.github.com>

.github/copilot-instructions.md

@@ -0,0 +1,10 @@
+This is a TypeScript-based repository with a Ruby client for certain API endpoints. It includes several sub projects called addons which are built separately. It contains a demo application which showcases the functionality of the project.
+
+Please follow these guidelines when contributing:
+
+## Development Flow
+
+- Install dependencies: `npm install && npm run setup`
+- Build and bundle demo: `npm run build && npm run esbuild`
+- Run unit tests: `npm run test-unit`
+- Run playwright-based integration tests: `npm run test-integration`

.github/workflows/copilot-setup-steps.yml

@@ -0,0 +1,36 @@
+name: "Copilot Setup Steps"
+
+on:
+  workflow_dispatch:
+  push:
+    paths:
+      - .github/workflows/copilot-setup-steps.yml
+  pull_request:
+    paths:
+      - .github/workflows/copilot-setup-steps.yml
+
+jobs:
+  copilot-setup-steps:
+    runs-on: ubuntu-latest
+
+    permissions:
+      contents: read
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Use Node.js 20.x
+        uses: actions/setup-node@v3
+        with:
+          node-version: 20.x
+          cache: 'yarn'
+
+      - name: Install dependencies
+        run: yarn --frozen-lockfile
+
+      - name: Setup and run tsc
+        run: yarn setup
+
+      - name: Esbuild
+        run: yarn esbuild

addons/addon-web-links/typings/addon-web-links.d.ts

@@ -14,6 +14,10 @@ declare module '@xterm/addon-web-links' {
     /**
      * Creates a new web links addon.
      * @param handler The callback when the link is called.
+     *
+     * Note that this may not work when the terminal is hosted inside an iframe,
+     * in that case provide a custom handler in that case being mindful of
+     * possible security issues like reverse tabnapping.
      * @param options Options for the link provider.
      */
     constructor(handler?: (event: MouseEvent, uri: string) => void, options?: ILinkProviderOptions);

addons/addon-webgl/src/CharAtlasUtils.ts

@@ -10,6 +10,15 @@ import { IColorSet, ReadonlyColorSet } from 'browser/Types';
 import { NULL_COLOR } from 'common/Color';
 
 export function generateConfig(deviceCellWidth: number, deviceCellHeight: number, deviceCharWidth: number, deviceCharHeight: number, options: Required<ITerminalOptions>, colors: ReadonlyColorSet, devicePixelRatio: number, deviceMaxTextureSize: number): ICharAtlasConfig {
+  // Convert lineHeight to a numeric multiplier for the char atlas
+  // If it's a px value, calculate the equivalent multiplier
+  let lineHeightMultiplier: number = typeof options.lineHeight === 'number' ? options.lineHeight : 1;
+  if (typeof options.lineHeight === 'string' && options.lineHeight.endsWith('px')) {
+    const pxValue = parseFloat(options.lineHeight.slice(0, -2));
+    // Calculate the multiplier based on font size
+    lineHeightMultiplier = pxValue / options.fontSize;
+  }
+
   // null out some fields that don't matter
   const clonedColors: IColorSet = {
     foreground: colors.foreground,
@@ -36,7 +45,7 @@ export function generateConfig(deviceCellWidth: number, deviceCellHeight: number
     devicePixelRatio,
     deviceMaxTextureSize,
     letterSpacing: options.letterSpacing,
-    lineHeight: options.lineHeight,
+    lineHeight: lineHeightMultiplier,
     deviceCellWidth: deviceCellWidth,
     deviceCellHeight: deviceCellHeight,
     deviceCharWidth: deviceCharWidth,

addons/addon-webgl/src/WebglRenderer.ts

@@ -27,6 +27,19 @@ import { addDisposableListener } from 'vs/base/browser/dom';
 import { combinedDisposable, Disposable, MutableDisposable, toDisposable } from 'vs/base/common/lifecycle';
 import { createRenderDimensions } from 'browser/renderer/shared/RendererUtils';
 
+/**
+ * Calculates the line height in pixels based on the lineHeight option and character height.
+ */
+function calculateLineHeightInPixels(lineHeight: number | string, charHeight: number): number {
+  if (typeof lineHeight === 'string' && lineHeight.endsWith('px')) {
+    const pxValue = parseFloat(lineHeight.slice(0, -2));
+    // Ensure the pixel value is at least as large as the character height
+    return Math.max(pxValue, charHeight);
+  }
+  // Numeric lineHeight acts as a multiplier
+  return Math.floor(charHeight * (lineHeight as number));
+}
+
 export class WebglRenderer extends Disposable implements IRenderer {
   private _renderLayers: IRenderLayer[];
   private _cursorBlinkStateManager: MutableDisposable<CursorBlinkStateManager> = new MutableDisposable();
@@ -570,14 +583,14 @@ export class WebglRenderer extends Disposable implements IRenderer {
     // cell.
     this.dimensions.device.char.height = Math.ceil(this._charSizeService.height * this._devicePixelRatio);
 
-    // Calculate the device cell height, if lineHeight is _not_ 1, the resulting value will be
+    // Calculate the device cell height, supporting both numeric multipliers and 'px' values
-    // floored since lineHeight can never be lower then 1, this guarentees the device cell height
+    this.dimensions.device.cell.height = calculateLineHeightInPixels(this._optionsService.rawOptions.lineHeight, this.dimensions.device.char.height);
-    // will always be larger than device char height.
-    this.dimensions.device.cell.height = Math.floor(this.dimensions.device.char.height * this._optionsService.rawOptions.lineHeight);
 
     // Calculate the y offset within a cell that glyph should draw at in order for it to be centered
     // correctly within the cell.
-    this.dimensions.device.char.top = this._optionsService.rawOptions.lineHeight === 1 ? 0 : Math.round((this.dimensions.device.cell.height - this.dimensions.device.char.height) / 2);
+    const isDefaultLineHeight = (typeof this._optionsService.rawOptions.lineHeight === 'number' && this._optionsService.rawOptions.lineHeight === 1) ||
+                               (typeof this._optionsService.rawOptions.lineHeight === 'string' && this.dimensions.device.cell.height === this.dimensions.device.char.height);
+    this.dimensions.device.char.top = isDefaultLineHeight ? 0 : Math.round((this.dimensions.device.cell.height - this.dimensions.device.char.height) / 2);
 
     // Calculate the device cell width, taking the letterSpacing into account.
     this.dimensions.device.cell.width = this.dimensions.device.char.width + Math.round(this._optionsService.rawOptions.letterSpacing);

package.json

@@ -95,7 +95,7 @@
     "jsdom": "^18.0.1",
     "mocha": "^10.1.0",
     "mustache": "^4.2.0",
-    "node-pty": "^1.1.0-beta31",
+    "node-pty": "1.1.0-beta19",
     "nyc": "^15.1.0",
     "source-map-loader": "^3.0.0",
     "source-map-support": "^0.5.20",

src/browser/renderer/LineHeight.test.ts

@@ -0,0 +1,78 @@
+/**
+ * Copyright (c) 2023 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { assert } from 'chai';
+
+/**
+ * Calculates the line height in pixels based on the lineHeight option and character height.
+ * This is the same function used in both DomRenderer and WebglRenderer.
+ */
+function calculateLineHeightInPixels(lineHeight: number | string, charHeight: number): number {
+  if (typeof lineHeight === 'string' && lineHeight.endsWith('px')) {
+    const pxValue = parseFloat(lineHeight.slice(0, -2));
+    // Ensure the pixel value is at least as large as the character height
+    return Math.max(pxValue, charHeight);
+  }
+  // Numeric lineHeight acts as a multiplier
+  return Math.floor(charHeight * (lineHeight as number));
+}
+
+describe('calculateLineHeightInPixels', () => {
+  describe('numeric lineHeight', () => {
+    it('should calculate correctly with multiplier 1', () => {
+      assert.equal(calculateLineHeightInPixels(1, 20), 20);
+    });
+
+    it('should calculate correctly with multiplier 1.2', () => {
+      assert.equal(calculateLineHeightInPixels(1.2, 20), 24);
+    });
+
+    it('should calculate correctly with multiplier 1.5', () => {
+      assert.equal(calculateLineHeightInPixels(1.5, 20), 30);
+    });
+
+    it('should floor the result', () => {
+      assert.equal(calculateLineHeightInPixels(1.3, 20), 26); // Math.floor(26)
+    });
+  });
+
+  describe('string lineHeight with px format', () => {
+    it('should use px value directly when larger than char height', () => {
+      assert.equal(calculateLineHeightInPixels('25px', 20), 25);
+    });
+
+    it('should use char height when px value is smaller', () => {
+      assert.equal(calculateLineHeightInPixels('15px', 20), 20);
+    });
+
+    it('should handle decimal px values', () => {
+      assert.equal(calculateLineHeightInPixels('23.5px', 20), 23.5);
+    });
+
+    it('should handle edge case where px equals char height', () => {
+      assert.equal(calculateLineHeightInPixels('20px', 20), 20);
+    });
+
+    it('should handle very large px values', () => {
+      assert.equal(calculateLineHeightInPixels('100px', 20), 100);
+    });
+  });
+
+  describe('edge cases', () => {
+    it('should handle zero char height with numeric multiplier', () => {
+      assert.equal(calculateLineHeightInPixels(1.5, 0), 0);
+    });
+
+    it('should handle zero char height with px value', () => {
+      assert.equal(calculateLineHeightInPixels('25px', 0), 25);
+    });
+
+    it('should handle 1px with various char heights', () => {
+      assert.equal(calculateLineHeightInPixels('1px', 5), 5);
+      assert.equal(calculateLineHeightInPixels('1px', 20), 20);
+      assert.equal(calculateLineHeightInPixels('1px', 0), 1);
+    });
+  });
+});

src/browser/renderer/dom/DomRenderer.ts

@@ -24,6 +24,19 @@ const BG_CLASS_PREFIX = 'xterm-bg-';
 const FOCUS_CLASS = 'xterm-focus';
 const SELECTION_CLASS = 'xterm-selection';
 
+/**
+ * Calculates the line height in pixels based on the lineHeight option and character height.
+ */
+function calculateLineHeightInPixels(lineHeight: number | string, charHeight: number): number {
+  if (typeof lineHeight === 'string' && lineHeight.endsWith('px')) {
+    const pxValue = parseFloat(lineHeight.slice(0, -2));
+    // Ensure the pixel value is at least as large as the character height
+    return Math.max(pxValue, charHeight);
+  }
+  // Numeric lineHeight acts as a multiplier
+  return Math.floor(charHeight * (lineHeight as number));
+}
+
 let nextTerminalId = 1;
 
 /**
@@ -116,7 +129,7 @@ export class DomRenderer extends Disposable implements IRenderer {
     this.dimensions.device.char.width = this._charSizeService.width * dpr;
     this.dimensions.device.char.height = Math.ceil(this._charSizeService.height * dpr);
     this.dimensions.device.cell.width = this.dimensions.device.char.width + Math.round(this._optionsService.rawOptions.letterSpacing);
-    this.dimensions.device.cell.height = Math.floor(this.dimensions.device.char.height * this._optionsService.rawOptions.lineHeight);
+    this.dimensions.device.cell.height = calculateLineHeightInPixels(this._optionsService.rawOptions.lineHeight, this.dimensions.device.char.height);
     this.dimensions.device.char.left = 0;
     this.dimensions.device.char.top = 0;
     this.dimensions.device.canvas.width = this.dimensions.device.cell.width * this._bufferService.cols;

src/common/buffer/Buffer.ts

@@ -320,37 +320,7 @@ export class Buffer implements IBuffer {
     if (toRemove.length > 0) {
       const newLayoutResult = reflowLargerCreateNewLayout(this.lines, toRemove);
       reflowLargerApplyNewLayout(this.lines, newLayoutResult.layout);
-
-      // For conpty, it has its own copy of the buffer _without scrollback_ internally. Its behavior
-      // when reflowing larger is to insert empty lines at the bottom of the buffer as when lines
-      // unwrap conpty's view cannot pull scrollback down, so it adds empty lines at the end.
-      let removedInViewport = 0;
-      const isWindowsMode = this._optionsService.rawOptions.windowsMode || this._optionsService.rawOptions.windowsPty.backend !== undefined || this._optionsService.rawOptions.windowsPty.buildNumber !== undefined;
-      if (isWindowsMode) {
-        for (let i = (toRemove.length / 2) - 1; i >= 0; i--) {
-          if (toRemove[i * 2 + 0] > this.ybase + removedInViewport) {
-            removedInViewport += toRemove[i * 2 + 1];
-          }
-        }
-      }
-
       this._reflowLargerAdjustViewport(newCols, newRows, newLayoutResult.countRemoved);
-
-      // Apply empty lines for any removed in viewport for conpty.
-      if (isWindowsMode) {
-        if (removedInViewport > 0) {
-          for (let i = 0; i < removedInViewport; i++) {
-            // Just add the new missing rows on Windows as conpty reprints the screen with it's
-            // view of the world. Once a line enters scrollback for conpty it remains there
-            this.lines.push(new BufferLine(newCols, this.getNullCell(DEFAULT_ATTR_DATA)));
-          }
-          if (this.ybase === this.ydisp) {
-            this.ydisp += removedInViewport;
-          }
-          this.ybase += removedInViewport;
-          this.y -= removedInViewport;
-        }
-      }
     }
   }
 
@@ -382,7 +352,7 @@ export class Buffer implements IBuffer {
     const nullCell = this.getNullCell(DEFAULT_ATTR_DATA);
     // Gather all BufferLines that need to be inserted into the Buffer here so that they can be
     // batched up and only committed once
-    const toInsert: { start: number, newLines: IBufferLine[] }[] = [];
+    const toInsert = [];
     let countToInsert = 0;
     // Go backwards as many lines may be trimmed and this will avoid considering them
     for (let y = this.lines.length - 1; y >= 0; y--) {
@@ -497,20 +467,6 @@ export class Buffer implements IBuffer {
       this.savedY = Math.min(this.savedY + linesToAdd, this.ybase + newRows - 1);
     }
 
-    // For conpty, it has its own copy of the buffer _without scrollback_ internally. Its behavior
-    // when reflowing smaller is to reflow all lines inside the viewport, and removing empty or
-    // whitespace only lines from the bottom, until non-whitespace is hit in order to prevent
-    // content from being pushed into the scrollback.
-    let addedInViewport = 0;
-    const isWindowsMode = this._optionsService.rawOptions.windowsMode || this._optionsService.rawOptions.windowsPty.backend !== undefined || this._optionsService.rawOptions.windowsPty.buildNumber !== undefined;
-    if (isWindowsMode) {
-      for (let i = toInsert.length - 1; i >= 0; i--) {
-        if (toInsert[i].start > this.ybase + addedInViewport) {
-          addedInViewport += toInsert[i].newLines.length;
-        }
-      }
-    }
-
     // Rearrange lines in the buffer if there are any insertions, this is done at the end rather
     // than earlier so that it's a single O(n) pass through the buffer, instead of O(n^2) from many
     // costly calls to CircularList.splice.
@@ -564,35 +520,6 @@ export class Buffer implements IBuffer {
         this.lines.onTrimEmitter.fire(amountToTrim);
       }
     }
-
-    // Apply empty lines to remove calculated earlier for conpty.
-    if (isWindowsMode) {
-      if (addedInViewport > 0) {
-        let emptyLinesAtBottom = 0;
-        for (let i = this.lines.length - 1; i >= this.ybase + this.y; i--) {
-          const line = this.lines.get(i) as BufferLine;
-          if (line.isWrapped || line.getTrimmedLength() > 0) {
-            break;
-          }
-          emptyLinesAtBottom++;
-        }
-        const emptyLinesToRemove = Math.min(addedInViewport, emptyLinesAtBottom);
-        if (emptyLinesToRemove > 0) {
-          for (let i = 0; i < emptyLinesToRemove; i++) {
-            this.lines.pop();
-          }
-          if (this.ybase === this.ydisp) {
-            this.ydisp -= emptyLinesToRemove;
-          }
-          this.ybase -= emptyLinesToRemove;
-          this.y += emptyLinesToRemove;
-          this.lines.onDeleteEmitter.fire({
-            index: this.lines.length - emptyLinesToRemove,
-            amount: emptyLinesToRemove
-          });
-        }
-      }
-    }
   }
 
   /**

src/common/input/Keyboard.test.ts

@@ -125,17 +125,17 @@ describe('Keyboard', () => {
     describe('On non-macOS platforms', () => {
       // Evalueate alt + arrow key movement, which is a feature of terminal emulators but not VT100
       // http://unix.stackexchange.com/a/108106
-      it('should return \\x1b[5D for alt+left', () => {
+      it('should return \\x1b[1;3D for alt+left', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 37 }, { isMac: false }).key, '\x1b[1;5D'); // CSI 5 D
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 37 }, { isMac: false }).key, '\x1b[1;3D'); // CSI 1;3 D
       });
-      it('should return \\x1b[5C for alt+right', () => {
+      it('should return \\x1b[1;3C for alt+right', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 39 }, { isMac: false }).key, '\x1b[1;5C'); // CSI 5 C
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 39 }, { isMac: false }).key, '\x1b[1;3C'); // CSI 1;3 C
       });
-      it('should return \\x1b[5D for alt+up', () => {
+      it('should return \\x1b[1;3A for alt+up', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }, { isMac: false }).key, '\x1b[1;5A'); // CSI 5 D
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }, { isMac: false }).key, '\x1b[1;3A'); // CSI 1;3 A
       });
-      it('should return \\x1b[5C for alt+down', () => {
+      it('should return \\x1b[1;3B for alt+down', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }, { isMac: false }).key, '\x1b[1;5B'); // CSI 5 C
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }, { isMac: false }).key, '\x1b[1;3B'); // CSI 1;3 B
       });
       it('should return \\x1ba for alt+a', () => {
         assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 65 }, { isMac: false }).key, '\x1ba');
@@ -149,17 +149,17 @@ describe('Keyboard', () => {
     });
 
     describe('On macOS platforms', () => {
-      it('should return \\x1bb for alt+left', () => {
+      it('should return \\x1b[1;3D for alt+left', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 37 }, { isMac: true }).key, '\x1bb'); // CSI 5 D
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 37 }, { isMac: true }).key, '\x1b[1;3D'); // CSI 1;3 D
       });
-      it('should return \\x1bf for alt+right', () => {
+      it('should return \\x1b[1;3C for alt+right', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 39 }, { isMac: true }).key, '\x1bf'); // CSI 5 C
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 39 }, { isMac: true }).key, '\x1b[1;3C'); // CSI 1;3 C
       });
-      it('should return \\x1bb for alt+up', () => {
+      it('should return \\x1b[1;3A for alt+up', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }, { isMac: true }).key, '\x1b[1;3A'); // CSI 5 D
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }, { isMac: true }).key, '\x1b[1;3A'); // CSI 1;3 A
       });
-      it('should return \\x1bf for alt+down', () => {
+      it('should return \\x1b[1;3B for alt+down', () => {
-        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }, { isMac: true }).key, '\x1b[1;3B'); // CSI 5 C
+        assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }, { isMac: true }).key, '\x1b[1;3B'); // CSI 1;3 B
       });
       it('should return undefined for alt+a', () => {
         assert.strictEqual(testEvaluateKeyboardEvent({ altKey: true, keyCode: 65 }, { isMac: true }).key, undefined);
@@ -176,11 +176,11 @@ describe('Keyboard', () => {
       });
     });
 
-    it('should return \\x1b[5A for alt+up', () => {
+    it('should return \\x1b[1;3A for alt+up', () => {
-      assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }).key, '\x1b[1;5A'); // CSI 5 A
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 38 }).key, '\x1b[1;3A'); // CSI 1;3 A
     });
-    it('should return \\x1b[5B for alt+down', () => {
+    it('should return \\x1b[1;3B for alt+down', () => {
-      assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }).key, '\x1b[1;5B'); // CSI 5 B
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, keyCode: 40 }).key, '\x1b[1;3B'); // CSI 1;3 B
     });
     it('should return the correct escape sequence for modified F1-F12 keys', () => {
       assert.equal(testEvaluateKeyboardEvent({ shiftKey: true, keyCode: 112 }).key, '\x1b[1;2P');
@@ -336,6 +336,19 @@ describe('Keyboard', () => {
       assert.equal(testEvaluateKeyboardEvent({ shiftKey: true, keyCode: 49, key: '!' }).key, '!');
     });
 
+    // Characters using alt+shift sequences (letters)
+    it('should return proper sequences for alt+shift+letter combinations', () => {
+      // Test alt+shift combinations produce uppercase letters
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: true, keyCode: 65 }).key, '\x1bA'); // alt+shift+a
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: true, keyCode: 72 }).key, '\x1bH'); // alt+shift+h
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: true, keyCode: 90 }).key, '\x1bZ'); // alt+shift+z
+
+      // Test alt without shift produces lowercase letters
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: false, keyCode: 65 }).key, '\x1ba'); // alt+a
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: false, keyCode: 72 }).key, '\x1bh'); // alt+h
+      assert.equal(testEvaluateKeyboardEvent({ altKey: true, shiftKey: false, keyCode: 90 }).key, '\x1bz'); // alt+z
+    });
+
     it('should return proper sequence for ctrl+@', () => {
       assert.equal(testEvaluateKeyboardEvent({ ctrlKey: true, shiftKey: true, keyCode: 50, key: '@' }).key, '\x00');
     });

src/common/input/Keyboard.ts

@@ -117,12 +117,6 @@ export function evaluateKeyboardEvent(
       }
       if (modifiers) {
         result.key = C0.ESC + '[1;' + (modifiers + 1) + 'D';
-        // HACK: Make Alt + left-arrow behave like Ctrl + left-arrow: move one word backwards
-        // http://unix.stackexchange.com/a/108106
-        // macOS uses different escape sequences than linux
-        if (result.key === C0.ESC + '[1;3D') {
-          result.key = C0.ESC + (isMac ? 'b' : '[1;5D');
-        }
       } else if (applicationCursorMode) {
         result.key = C0.ESC + 'OD';
       } else {
@@ -136,12 +130,6 @@ export function evaluateKeyboardEvent(
       }
       if (modifiers) {
         result.key = C0.ESC + '[1;' + (modifiers + 1) + 'C';
-        // HACK: Make Alt + right-arrow behave like Ctrl + right-arrow: move one word forward
-        // http://unix.stackexchange.com/a/108106
-        // macOS uses different escape sequences than linux
-        if (result.key === C0.ESC + '[1;3C') {
-          result.key = C0.ESC + (isMac ? 'f' : '[1;5C');
-        }
       } else if (applicationCursorMode) {
         result.key = C0.ESC + 'OC';
       } else {
@@ -155,12 +143,6 @@ export function evaluateKeyboardEvent(
       }
       if (modifiers) {
         result.key = C0.ESC + '[1;' + (modifiers + 1) + 'A';
-        // HACK: Make Alt + up-arrow behave like Ctrl + up-arrow
-        // http://unix.stackexchange.com/a/108106
-        // macOS uses different escape sequences than linux
-        if (!isMac && result.key === C0.ESC + '[1;3A') {
-          result.key = C0.ESC + '[1;5A';
-        }
       } else if (applicationCursorMode) {
         result.key = C0.ESC + 'OA';
       } else {
@@ -174,12 +156,6 @@ export function evaluateKeyboardEvent(
       }
       if (modifiers) {
         result.key = C0.ESC + '[1;' + (modifiers + 1) + 'B';
-        // HACK: Make Alt + down-arrow behave like Ctrl + down-arrow
-        // http://unix.stackexchange.com/a/108106
-        // macOS uses different escape sequences than linux
-        if (!isMac && result.key === C0.ESC + '[1;3B') {
-          result.key = C0.ESC + '[1;5B';
-        }
       } else if (applicationCursorMode) {
         result.key = C0.ESC + 'OB';
       } else {

src/common/services/OptionsService.lineHeight.test.ts

@@ -0,0 +1,86 @@
+/**
+ * Copyright (c) 2023 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
+import { assert } from 'chai';
+import { OptionsService } from 'common/services/OptionsService';
+
+describe('OptionsService lineHeight', () => {
+  let optionsService: OptionsService;
+
+  beforeEach(() => {
+    optionsService = new OptionsService({});
+  });
+
+  describe('numeric lineHeight', () => {
+    it('should accept numeric values', () => {
+      optionsService.options.lineHeight = 1.5;
+      assert.equal(optionsService.rawOptions.lineHeight, 1.5);
+    });
+
+    it('should reject values less than 1', () => {
+      assert.throws(() => optionsService.options.lineHeight = 0.5);
+    });
+
+    it('should accept 1 as minimum value', () => {
+      optionsService.options.lineHeight = 1;
+      assert.equal(optionsService.rawOptions.lineHeight, 1);
+    });
+  });
+
+  describe('string lineHeight with px format', () => {
+    it('should accept px values', () => {
+      optionsService.options.lineHeight = '24px';
+      assert.equal(optionsService.rawOptions.lineHeight, '24px');
+    });
+
+    it('should accept decimal px values', () => {
+      optionsService.options.lineHeight = '23.5px';
+      assert.equal(optionsService.rawOptions.lineHeight, '23.5px');
+    });
+
+    it('should reject px values less than 1', () => {
+      assert.throws(() => optionsService.options.lineHeight = '0.5px');
+    });
+
+    it('should accept 1px as minimum value', () => {
+      optionsService.options.lineHeight = '1px';
+      assert.equal(optionsService.rawOptions.lineHeight, '1px');
+    });
+
+    it('should reject non-px string values', () => {
+      assert.throws(() => optionsService.options.lineHeight = '24' as any);
+      assert.throws(() => optionsService.options.lineHeight = '24em' as any);
+      assert.throws(() => optionsService.options.lineHeight = 'normal' as any);
+    });
+
+    it('should reject invalid px values', () => {
+      assert.throws(() => optionsService.options.lineHeight = 'invalidpx' as any);
+      assert.throws(() => optionsService.options.lineHeight = 'px' as any);
+    });
+  });
+
+  describe('invalid lineHeight types', () => {
+    it('should reject null', () => {
+      assert.throws(() => optionsService.options.lineHeight = null as any);
+    });
+
+    it('should reject undefined when explicitly set', () => {
+      assert.throws(() => optionsService.options.lineHeight = undefined as any);
+    });
+
+    it('should reject boolean values', () => {
+      assert.throws(() => optionsService.options.lineHeight = true as any);
+      assert.throws(() => optionsService.options.lineHeight = false as any);
+    });
+
+    it('should reject arrays', () => {
+      assert.throws(() => optionsService.options.lineHeight = [] as any);
+    });
+
+    it('should reject objects', () => {
+      assert.throws(() => optionsService.options.lineHeight = {} as any);
+    });
+  });
+});

src/common/services/OptionsService.ts

@@ -172,12 +172,31 @@ export class OptionsService extends Disposable implements IOptionsService {
       case 'cursorWidth':
         value = Math.floor(value);
         // Fall through for bounds check
-      case 'lineHeight':
       case 'tabStopWidth':
         if (value < 1) {
           throw new Error(`${key} cannot be less than 1, value: ${value}`);
         }
         break;
+      case 'lineHeight':
+        if (typeof value === 'string') {
+          // Handle 'px' format
+          if (value.endsWith('px')) {
+            const pxValue = parseFloat(value.slice(0, -2));
+            if (isNaN(pxValue) || pxValue < 1) {
+              throw new Error(`${key} with 'px' format must be a valid number >= 1, value: ${value}`);
+            }
+            // Keep the string value as-is for downstream processing
+          } else {
+            throw new Error(`${key} string value must end with 'px', value: ${value}`);
+          }
+        } else if (typeof value === 'number') {
+          if (value < 1) {
+            throw new Error(`${key} cannot be less than 1, value: ${value}`);
+          }
+        } else {
+          throw new Error(`${key} must be a number or string with 'px' suffix, value: ${value}`);
+        }
+        break;
       case 'minimumContrastRatio':
         value = Math.max(1, Math.min(21, Math.round(value * 10) / 10));
         break;

src/common/services/Services.ts

@@ -231,7 +231,7 @@ export interface ITerminalOptions {
   fontWeightBold?: FontWeight;
   ignoreBracketedPasteMode?: boolean;
   letterSpacing?: number;
-  lineHeight?: number;
+  lineHeight?: number | string;
   linkHandler?: ILinkHandler | null;
   logLevel?: LogLevel;
   logger?: ILogger | null;

typings/xterm-headless.d.ts

@@ -94,9 +94,11 @@ declare module '@xterm/headless' {
     letterSpacing?: number;
 
     /**
-     * The line height used to render text.
+     * The line height used to render text. This can be specified as:
+     * - A number (e.g., 1.2) which acts as a multiplier of the font size
+     * - A string with 'px' suffix (e.g., '24px') which specifies an absolute pixel height
      */
-    lineHeight?: number;
+    lineHeight?: number | string;
 
     /**
      * What log level to use, this will log for all levels below and including

typings/xterm.d.ts

@@ -152,9 +152,11 @@ declare module '@xterm/xterm' {
     letterSpacing?: number;
 
     /**
-     * The line height used to render text.
+     * The line height used to render text. This can be specified as:
+     * - A number (e.g., 1.2) which acts as a multiplier of the font size
+     * - A string with 'px' suffix (e.g., '24px') which specifies an absolute pixel height
      */
-    lineHeight?: number;
+    lineHeight?: number | string;
 
     /**
      * The handler for OSC 8 hyperlinks. Links will use the `confirm` browser

yarn.lock

@@ -3302,10 +3302,10 @@ node-preload@^0.2.1:
   dependencies:
     process-on-spawn "^1.0.0"
 
-node-pty@^1.1.0-beta31:
+node-pty@1.1.0-beta19:
-  version "1.1.0-beta9"
+  version "1.1.0-beta19"
-  resolved "https://registry.yarnpkg.com/node-pty/-/node-pty-1.1.0-beta9.tgz#ed643cb3b398d031b4e31c216e8f3b0042435f1d"
+  resolved "https://registry.yarnpkg.com/node-pty/-/node-pty-1.1.0-beta19.tgz#a74dc04429903c5ac49ee81a15a24590da67d4f3"
-  integrity sha512-/Ue38pvXJdgRZ3+me1FgfglLd301GhJN0NStiotdt61tm43N5htUyR/IXOUzOKuNaFmCwIhy6nwb77Ky41LMbw==
+  integrity sha512-/p4Zu56EYDdXjjaLWzrIlFyrBnND11LQGP0/L6GEVGURfCNkAlHc3Twg/2I4NPxghimHXgvDlwp7Z2GtvDIh8A==
   dependencies:
     node-addon-api "^7.1.0"