New unicode-graphemes addon.

Handle grapheme cluster lookup as well as wcwidth.
This is based on Unicode 15, and could replace the unicode11 addon.

src/common/services/UnicodeService.ts

@@ -2,7 +2,7 @@
  * Copyright (c) 2019 The xterm.js authors. All rights reserved.
  * @license MIT
  */
-import { IUnicodeService, IUnicodeVersionProvider } from 'common/services/Services';
+import { IUnicodeService, IUnicodeVersionProvider, UnicodeCharProperties, UnicodeCharWidth  } from 'common/services/Services';
 import { EventEmitter, IEvent } from 'common/EventEmitter';
 import { UnicodeV6 } from 'common/input/UnicodeV6';
 
@@ -16,6 +16,19 @@ export class UnicodeService implements IUnicodeService {
   private readonly _onChange = new EventEmitter<string>();
   public readonly onChange = this._onChange.event;
 
+  public static extractShouldJoin(value: UnicodeCharProperties): boolean {
+    return (value & 1) !== 0;
+  }
+  public static extractWidth(value: UnicodeCharProperties): UnicodeCharWidth {
+    return ((value >> 1) & 0x3) as UnicodeCharWidth;
+  }
+  public static extractCharKind(value: UnicodeCharProperties): number {
+    return value >> 3;
+  }
+  public static createPropertyValue(state: number, width: number, shouldJoin: boolean = false): UnicodeCharProperties {
+    return ((state & 0xffffff) << 3) | ((width & 3) << 1) | (shouldJoin?1:0);
+  }
+
   constructor() {
     const defaultProvider = new UnicodeV6();
     this.register(defaultProvider);
@@ -51,7 +64,7 @@ export class UnicodeService implements IUnicodeService {
   /**
    * Unicode version dependent interface.
    */
-  public wcwidth(num: number): number {
+  public wcwidth(num: number): UnicodeCharWidth {
     return this._activeProvider.wcwidth(num);
   }
 
@@ -83,4 +96,8 @@ export class UnicodeService implements IUnicodeService {
     }
     return result;
   }
+
+  charProperties(codepoint: number, preceding: UnicodeCharProperties): UnicodeCharProperties {
+    return this._activeProvider.charProperties(codepoint, preceding);
+  }
 }