src/vs/workbench/services/textMate/browser/abstractTextMateService.ts/AbstractTextMateService/equalsTokenRules
class AbstractTextMateService:	private static equalsTokenRules(a: ITextMateThemingRule[] | null, b: ITextMateThemingRule[] | null): boolean {
		if (!b || !a || b.length !== a.length) {
			return false;
		}
		for (let i = b.length - 1; i >= 0; i--) {
			let r1 = b[i];
			let r2 = a[i];
			if (r1.scope !== r2.scope) {
				return false;
			}
			let s1 = r1.settings;
			let s2 = r2.settings;
			if (s1 && s2) {
				if (s1.fontStyle !== s2.fontStyle || s1.foreground !== s2.foreground || s1.background !== s2.background) {
					return false;
				}
			} else if (!s1 || !s2) {
				return false;
			}
		}
		return true;
	}