Function createDeferredBlock

packages/compiler/src/render3/r3_deferred_blocks.ts:58–104

(
  ast: html.Block,
  connectedBlocks: html.Block[],
  visitor: html.Visitor,
  bindingParser: BindingParser,
)

/** Creates a deferred block from an HTML AST node. */
export function createDeferredBlock(
  ast: html.Block,
  connectedBlocks: html.Block[],
  visitor: html.Visitor,
  bindingParser: BindingParser,
): {node: t.DeferredBlock; errors: ParseError[]} {
  const errors: ParseError[] = [];
  const {placeholder, loading, error} = parseConnectedBlocks(connectedBlocks, errors, visitor);
  const {triggers, prefetchTriggers, hydrateTriggers} = parsePrimaryTriggers(
    ast,
    bindingParser,
    errors,
    placeholder,
  );

  // The `defer` block has a main span encompassing all of the connected branches as well.
  let lastEndSourceSpan = ast.endSourceSpan;
  let endOfLastSourceSpan = ast.sourceSpan.end;
  if (connectedBlocks.length > 0) {
    const lastConnectedBlock = connectedBlocks[connectedBlocks.length - 1];
    lastEndSourceSpan = lastConnectedBlock.endSourceSpan;
    endOfLastSourceSpan = lastConnectedBlock.sourceSpan.end;
  }

  const sourceSpanWithConnectedBlocks = new ParseSourceSpan(
    ast.sourceSpan.start,
    endOfLastSourceSpan,
  );

  const node = new t.DeferredBlock(
    html.visitAll(visitor, ast.children, ast.children),
    triggers,
    prefetchTriggers,
    hydrateTriggers,
    placeholder,
    loading,
    error,
    ast.nameSpan,
    sourceSpanWithConnectedBlocks,
    ast.sourceSpan,
    ast.startSourceSpan,
    lastEndSourceSpan,
    ast.i18n,
  );

  return {node, errors};
}

function parseConnectedBlocks(
  connectedBlocks: html.Block[],