docs(ScreenshotStream API): change isRecording to canCapture for clarity

packages/core/src/provenance/screenshot-stream.ts

@@ -110,6 +110,15 @@ export function intitializeScreenshotStream(): ScreenshotStream {
  }
  }
 
+ /**
+ * False if the MediaStream has not been initialized via start(), or has been stopped.
+ * True if we have a MediaStream and can capture screenshots.
+ * @returns Whether a screenshot can be captured.
+ */
+ function canCapture(): boolean {
+ return video !== null;
+ }
+
  /**
  * Captures a screenshot and stores it in the screenshots array.
  * Also pushes the screenshot to the newScreenshotCallback if available.
@@ -118,7 +127,9 @@ export function intitializeScreenshotStream(): ScreenshotStream {
  * @returns The captured screenshot.
  */
  function capture(): ImageData {
- if (!video) {
+ // We need the null check for ts, but canCapture() does that check already.
+ // We include canCapture() in case the implementation changes.
+ if (!canCapture() || !video) {
  throw new Error('Recording not started');
  }
 
@@ -197,14 +208,6 @@ export function intitializeScreenshotStream(): ScreenshotStream {
  return [...screenshots];
  }
 
- /**
- * Returns whether the screenshot stream is currently recording.
- * @returns Whether the screenshot stream is currently recording.
- */
- function isRecording(): boolean {
- return video !== null;
- }
-
  /**
  * Registers a listener to be called when a new screenshot is captured.
  * @param listener - The listener to be called when a new screenshot is captured.
@@ -230,7 +233,7 @@ export function intitializeScreenshotStream(): ScreenshotStream {
  getNth,
  count,
  getAll,
- isRecording,
+ canCapture: canCapture,
  registerScreenshotListener,
  };
 }

packages/core/src/provenance/trrack.ts

@@ -307,7 +307,7 @@ export function initializeTrrack<State = any, Event extends string = string>({
  });
  }
 
- if (screenshots.isRecording() && action.triggersScreenshot)
+ if (screenshots.canCapture() && action.triggersScreenshot)
  screenshots.delayCapture(action.transitionTime);
  },
  async to(node: NodeId) {
@@ -327,7 +327,7 @@ export function initializeTrrack<State = any, Event extends string = string>({
  for (let i = 0; i < path.length - 1; ++i) {
  const currentNode = getNode(path[i]);
 
- if (screenshots.isRecording()) {
+ if (screenshots.canCapture()) {
  const action = registry.get(currentNode.event);
  if (
  action.triggersScreenshot &&
@@ -359,7 +359,7 @@ export function initializeTrrack<State = any, Event extends string = string>({
 
  graph.update(graph.changeCurrent(node));
 
- if (screenshots.isRecording() && maxTimer >= 0) {
+ if (screenshots.canCapture() && maxTimer >= 0) {
  screenshots.delayCapture(maxTimer);
  }
 
@@ -396,7 +396,7 @@ export function initializeTrrack<State = any, Event extends string = string>({
  });
  },
  done() {
- if (screenshots.isRecording()) screenshots.stop();
+ if (screenshots.canCapture()) screenshots.stop();
  console.log('Setup later for URL sharing.');
  },
  tree() {

packages/core/src/provenance/types.ts

@@ -57,9 +57,9 @@ export interface ScreenshotStream {
  */
  getAll(): ImageData[];
  /**
- * Returns whether the screenshot stream is currently recording.
+ * @returns whether capturing is allowed. Generally is false before start() is called and after stop() is called.
  */
- isRecording(): boolean;
+ canCapture(): boolean;
  /**
  * Registers a listener to be called when a screenshot is captured.
  * @param listener - The listener to register.