Bringing the XSLT version to the context, to be used to implement `up…

…per-case` and `lower-case` functions. (#33)

src/xpath/expr-context.ts

@@ -7,7 +7,8 @@ import { TOK_NUMBER } from './tokens';
 import { XNode } from '../dom';
 import { XsltDecimalFormatSettings } from '../xslt/xslt-decimal-format-settings';
 
-/** XPath expression evaluation context. An XPath context consists of a
+/**
+ * XPath expression evaluation context. An XPath context consists of a
  * DOM node, a list of DOM nodes that contains this node, a number
  * that represents the position of the single node in the list, and a
  * current set of variable bindings. (See XPath spec.)
@@ -46,6 +47,7 @@ export class ExprContext {
     outputPosition: number;
     outputNodeList: XNode[];
     outputDepth: number;
+    xsltVersion: '1.0' | '2.0' | '3.0';
 
     variables: { [name: string]: any };
     knownNamespaces: { [alias: string]: string };

src/xslt/xslt.ts

@@ -606,6 +606,7 @@ export class Xslt {
                             `XSLT version not defined or invalid. Actual resolved version: ${this.version || '(none)'}.`
                         );
                     }
+                    context.xsltVersion = this.version as any;
                     break;
                 default:
                     if (stylesheetAttribute.prefix === 'xmlns') {