easysync: add clear method to stringAssembler

Author: webzwo0i

src/static/js/Changeset.js

@@ -587,9 +587,11 @@ exports.stringAssembler = () => {
   };
 
   const toString = () => pieces.join('');
+  const clear = () => pieces.length = 0;
   return {
     append,
     toString,
+    clear,
   };
 };
 

src/tests/frontend/specs/easysync-assembler.js

@@ -171,7 +171,7 @@ describe('easysync', function () {
     expect(assem.toString()).to.equal('*3*4*5|3+f*1*4*5|1+1*1*4*5+4');
   });
 
-  xit('smartOpAssembler clear should empty internal assemblers', async function () {
+  it('smartOpAssembler clear should empty internal assemblers', async function () {
     const x = '-c*3*4+6|3=az*asdf0*1*2*3+1=1-1+1*0+1=1-1+1|c=c-1';
     const iter = Changeset.opIterator(x);
     const assem = Changeset.smartOpAssembler();