tricu

syntax-probe.mjs (3002B)

---

 // CodeMirror document, selection, highlighting and viewport checks.
 import {sourceEditor as editor,el,wait,status,pause} from './source-probe-helpers.mjs';
 const assert=(ok,message)=>{if(!ok)throw Error(message);};
 export async function syntaxProbe(){
  for(let i=0;editor.isDisabled;i++){assert(i<3600,'Source editable');await pause(25);}
  const initiallyPublished=el('status').textContent==='Ready';
  const dom=editor.dom,saved=editor.getSource(),frame=()=>new Promise(r=>requestAnimationFrame(()=>requestAnimationFrame(r)));
  assert(dom.querySelector('.syntax-definition'),'Loaded declarations highlighted');
  assert(dom.querySelector('[contenteditable=true][aria-label]')&&!dom.querySelector('textarea,.syntax-viewport'),'Single accessible editing surface');
  assert(document.querySelector('#source .syntax-definition'),'Read-only source shares tokens');
  const set=value=>editor.replaceSource(value,true),caret=position=>editor.select(position);
  set('let named x = [x (t)] in named "λ🙂["');
  assert(dom.querySelector('.syntax-definition').textContent==='named','Local declaration color');
  assert(getComputedStyle(dom.querySelector('.syntax-definition')).color!==getComputedStyle(dom.querySelector('.syntax-name')).color,'Definition color');
  caret(editor.getSource().indexOf('['));assert(dom.querySelectorAll('.bracket-match').length===2,'Bracket pair');
  caret(editor.getSource().lastIndexOf('['));assert(!dom.querySelector('.bracket-match'),'String brackets ignored');
  editor.select(0,4);assert(!dom.querySelector('.bracket-match'),'Range has no caret match');
  set('(t');caret(0);assert(dom.querySelector('.bracket-unmatched'),'Unclosed delimiter');
  set('<img src=x onerror="throw 1">');assert(!dom.querySelector('img')&&editor.getSource()==='<img src=x onerror="throw 1">','Source markup remains literal text');
  dom.dispatchEvent(new CompositionEvent('compositionstart'));
  assert(dom.classList.contains('composing'),'Composition lifecycle observed');
  set('"λ🙂"');dom.dispatchEvent(new CompositionEvent('compositionend'));assert(!dom.classList.contains('composing'),'Composition lifecycle ends');
  const large=Array.from({length:1000},(_,i)=>`x${i} = ${i}`).join('\n')+'\n';set(large);await frame();
  assert(editor.getSource()===large&&dom.querySelectorAll('.cm-line').length<1000,'Virtualization preserves complete document and trailing newline');
  editor.select(large.length);await frame();assert(editor.getSelection().to===large.length,'Selection uses canonical UTF-16 offsets beyond viewport');
  set(saved);editor.view.contentDOM.blur();editor.view.scrollDOM.scrollTop=0;
  await pause(0);await wait(()=>['Compiled','Ready'].includes(el('status').textContent)&&!editor.isDisabled,'source restoration');
  // A slow engine can finish a compilation during the rendering stress check.
  // Restore the original published session after that compilation completes.
  if(initiallyPublished&&el('status').textContent==='Compiled'){el('restore-source').click();await status('Ready');}
 }