Cleanup of MathML to avoids some common input errors.

Author: zorkow

lib/v3-lab.js

@@ -158,6 +158,21 @@ const Lab = window.Lab = {
         return math;
     },
 
+    readInput() {
+      let input = this.input.value;
+      if (this.format !== 'MathML') {
+        return input;
+      }
+      input = input.trim();
+      if (!input.match(/^<math/)) {
+        input = '<math>' + input;
+      }
+      if (!input.match(/\/math>$/)) {
+        input += '</math>';
+      }
+      return input;
+    },
+
     /**
      * Perform the typesetting of the math in the proper format
      */
@@ -175,7 +190,7 @@ const Lab = window.Lab = {
         //   set its metrics, and link it to the text element created above, then
         //   add it to the document's math list.
         //
-        this.mathItem = this.MathItem(this.input.value, this.output);
+        this.mathItem = this.MathItem(this.readInput(), this.output);
         this.doc.clear();
         this.doc.math.push(this.mathItem);