function getMarkedFunctionId()

in packages/transform/src/visit.js [266:310]

• 33 lines of code
• 4 McCabe index (conditional complexity)

function getMarkedFunctionId(funPath) {
  const t = util.getTypes();
  const node = funPath.node;
  t.assertIdentifier(node.id);

  const blockPath = funPath.findParent(function (path) {
    return path.isProgram() || path.isBlockStatement();
  });

  if (!blockPath) {
    return node.id;
  }

  const block = blockPath.node;
  assert.ok(Array.isArray(block.body));

  const info = getMarkInfo(block);
  if (!info.decl) {
    info.decl = t.variableDeclaration("var", []);
    blockPath.unshiftContainer("body", info.decl);
    info.declPath = blockPath.get("body.0");
  }

  assert.strictEqual(info.declPath.node, info.decl);

  // Get a new unique identifier for our marked variable.
  const markedId = blockPath.scope.generateUidIdentifier("marked");
  const markCallExp = t.callExpression(
    util.runtimeProperty("mark"),
    [t.clone(node.id)]
  );

  const index = info.decl.declarations.push(
    t.variableDeclarator(markedId, markCallExp)
  ) - 1;

  const markCallExpPath =
    info.declPath.get("declarations." + index + ".init");

  assert.strictEqual(markCallExpPath.node, markCallExp);

  markCallExpPath.addComment("leading", "#__PURE__");

  return t.clone(markedId);
}