Function pushImg

packages/react-dom-bindings/src/server/ReactFizzConfigDOM.js:3300–3461

(
  target: Array<Chunk | PrecomputedChunk>,
  props: Object,
  resumableState: ResumableState,
  renderState: RenderState,
  hoistableState: null | HoistableState,
  formatContext: FormatContext,
)

}

function pushImg(
  target: Array<Chunk | PrecomputedChunk>,
  props: Object,
  resumableState: ResumableState,
  renderState: RenderState,
  hoistableState: null | HoistableState,
  formatContext: FormatContext,
): null {
  const pictureOrNoScriptTagInScope =
    formatContext.tagScope & (PICTURE_SCOPE | NOSCRIPT_SCOPE);
  const {src, srcSet} = props;
  if (
    props.loading !== 'lazy' &&
    (src || srcSet) &&
    (typeof src === 'string' || src == null) &&
    (typeof srcSet === 'string' || srcSet == null) &&
    props.fetchPriority !== 'low' &&
    !pictureOrNoScriptTagInScope &&
    // We exclude data URIs in src and srcSet since these should not be preloaded
    !(
      typeof src === 'string' &&
      src[4] === ':' &&
      (src[0] === 'd' || src[0] === 'D') &&
      (src[1] === 'a' || src[1] === 'A') &&
      (src[2] === 't' || src[2] === 'T') &&
      (src[3] === 'a' || src[3] === 'A')
    ) &&
    !(
      typeof srcSet === 'string' &&
      srcSet[4] === ':' &&
      (srcSet[0] === 'd' || srcSet[0] === 'D') &&
      (srcSet[1] === 'a' || srcSet[1] === 'A') &&
      (srcSet[2] === 't' || srcSet[2] === 'T') &&
      (srcSet[3] === 'a' || srcSet[3] === 'A')
    )
  ) {
    // We have a suspensey image and ought to preload it to optimize the loading of display blocking
    // resumableState.

    if (hoistableState !== null) {
      // Mark this boundary's state as having suspensey images.
      // Only do that if we have a ViewTransition that might trigger a parent Suspense boundary
      // to animate its appearing. Since that's the only case we'd actually apply suspensey images
      // for SSR reveals.
      const isInSuspenseWithEnterViewTransition =
        formatContext.tagScope & APPEARING_SCOPE;
      if (isInSuspenseWithEnterViewTransition) {
        hoistableState.suspenseyImages = true;
      }
    }

    const sizes = typeof props.sizes === 'string' ? props.sizes : undefined;
    const key = getImageResourceKey(src, srcSet, sizes);

    const promotablePreloads = renderState.preloads.images;

    let resource = promotablePreloads.get(key);
    if (resource) {