Merge branch 'updated_wcwidth' of github.com:jerch/xterm.js into updated_wcwidth

src/common/services/OptionsService.ts

@@ -37,6 +37,7 @@ export const DEFAULT_OPTIONS: ITerminalOptions = Object.freeze({
   screenReaderMode: false,
   macOptionIsMeta: false,
   macOptionClickForcesSelection: false,
+  minimumContrastRatio: 1,
   disableStdin: false,
   allowTransparency: false,
   tabStopWidth: 8,
@@ -117,6 +118,8 @@ export class OptionsService implements IOptionsService {
           throw new Error(`${key} cannot be less than 1, value: ${value}`);
         }
         break;
+      case 'minimumContrastRatio':
+        value = Math.max(1, Math.min(21, Math.round(value * 10) / 10));
       case 'scrollback':
         value = Math.min(value, 4294967295);
         if (value < 0) {

src/common/services/Services.ts

@@ -237,6 +237,7 @@ export interface ITerminalOptions {
   logLevel: LogLevel;
   macOptionIsMeta: boolean;
   macOptionClickForcesSelection: boolean;
+  minimumContrastRatio: number;
   rendererType: RendererType;
   rightClickSelectsWord: boolean;
   rows: number;

src/common/services/UnicodeService.ts

@@ -0,0 +1,75 @@
+/**
+ * Copyright (c) 2019 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+import { IUnicodeService, IUnicodeVersionProvider } from 'common/services/Services';
+import { EventEmitter, IEvent } from 'common/EventEmitter';
+
+
+export class UnicodeService implements IUnicodeService {
+  private _providers: {[key: string]: IUnicodeVersionProvider} = Object.create(null);
+  private _active: string = '';
+  private _onRegister = new EventEmitter<string>();
+  public get onRegister(): IEvent<string> { return this._onRegister.event; }
+  private _onChange = new EventEmitter<string>();
+  public get onChange(): IEvent<string> { return this._onChange.event; }
+
+  public get versions(): string[] {
+    return Object.keys(this._providers);
+  }
+
+  public get activeVersion(): string {
+    return this._active;
+  }
+
+  public set activeVersion(version: string) {
+    if (!this._providers[version]) {
+      throw new Error(`unknown Unicode version "${version}"`);
+    }
+    this._active = version;
+    this.wcwidth = (num: number) => this._providers[version].wcwidth(num);  // perf an issue here?
+    this._onChange.fire(version);
+  }
+
+  public registerVersion(provider: IUnicodeVersionProvider): void {
+    this._providers[provider.version] = provider;
+    this._onRegister.fire(provider.version);
+    if (!this.activeVersion) {
+      this.activeVersion = provider.version;
+    }
+  }
+
+  /**
+   * Unicode version dependent interface.
+   */
+  public wcwidth: (num: number) => number = () => { throw new Error('no Unicode version registered and activated'); }
+
+  public getStringCellWidth(s: string): number {
+    let result = 0;
+    const length = s.length;
+    for (let i = 0; i < length; ++i) {
+      let code = s.charCodeAt(i);
+      // surrogate pair first
+      if (0xD800 <= code && code <= 0xDBFF) {
+        if (++i >= length) {
+          // this should not happen with strings retrieved from
+          // Buffer.translateToString as it converts from UTF-32
+          // and therefore always should contain the second part
+          // for any other string we still have to handle it somehow:
+          // simply treat the lonely surrogate first as a single char (UCS-2 behavior)
+          return result + this.wcwidth(code);
+        }
+        const second = s.charCodeAt(i);
+        // convert surrogate pair to high codepoint only for valid second part (UTF-16)
+        // otherwise treat them independently (UCS-2 behavior)
+        if (0xDC00 <= second && second <= 0xDFFF) {
+          code = (code - 0xD800) * 0x400 + second - 0xDC00 + 0x10000;
+        } else {
+          result += this.wcwidth(second);
+        }
+      }
+      result += this.wcwidth(code);
+    }
+    return result;
+  }
+}