[breakpoints] Fix timing issue with syncing breakpoints (firefox-devtools#6553)

Author: jasonLaster

src/actions/breakpoints.js

@@ -52,14 +52,20 @@ export function syncBreakpoint(
   pendingBreakpoint: PendingBreakpoint
 ) {
   return async ({ dispatch, getState, client, sourceMaps }: ThunkArgs) => {
-    const { breakpoint, previousLocation } = await syncClientBreakpoint(
+    const response = await syncClientBreakpoint(
       getState,
       client,
       sourceMaps,
       sourceId,
       pendingBreakpoint
     );
 
+    if (!response) {
+      return;
+    }
+
+    const { breakpoint, previousLocation } = response;
+
     return dispatch(
       ({
         type: "SYNC_BREAKPOINT",

src/actions/breakpoints/syncBreakpoint.js

@@ -14,7 +14,7 @@ import {
 import { getGeneratedLocation } from "../../utils/source-maps";
 import { getTextAtPosition } from "../../utils/source";
 import { originalToGeneratedId } from "devtools-source-map";
-import { getSourceFromId } from "../../selectors";
+import { getSource } from "../../selectors";
 import type {
   Location,
   ASTLocation,
@@ -76,16 +76,20 @@ export async function syncClientBreakpoint(
   sourceMaps: Object,
   sourceId: SourceId,
   pendingBreakpoint: PendingBreakpoint
-): Promise<BreakpointSyncData> {
+): Promise<BreakpointSyncData | null> {
   assertPendingBreakpoint(pendingBreakpoint);
 
-  const source = getSourceFromId(getState(), sourceId);
+  const source = getSource(getState(), sourceId);
 
   const generatedSourceId = sourceMaps.isOriginalId(sourceId)
     ? originalToGeneratedId(sourceId)
     : sourceId;
 
-  const generatedSource = getSourceFromId(getState(), generatedSourceId);
+  const generatedSource = getSource(getState(), generatedSourceId);
+
+  if (!source) {
+    return null;
+  }
 
   const { location, astLocation } = pendingBreakpoint;
   const previousLocation = { ...location, sourceId };

src/actions/sources/newSources.js

@@ -136,10 +136,10 @@ function checkPendingBreakpoints(sourceId: string) {
     // load the source text if there is a pending breakpoint for it
     await dispatch(loadSourceText(source));
 
-    const pendingBreakpointsArray = pendingBreakpoints.valueSeq().toJS();
-    for (const pendingBreakpoint of pendingBreakpointsArray) {
-      await dispatch(syncBreakpoint(sourceId, pendingBreakpoint));
-    }
+    const breakpoints = pendingBreakpoints.valueSeq().toJS();
+    await Promise.all(
+      breakpoints.map(bp => dispatch(syncBreakpoint(sourceId, bp)))
+    );
   };
 }
 

src/utils/source.js

@@ -334,7 +334,7 @@ export function isLoading(source: Source) {
   return source.loadedState === "loading";
 }
 
-export function getTextAtPosition(source: Source, location: Location) {
+export function getTextAtPosition(source: ?Source, location: Location) {
   if (!source || !source.text || source.isWasm) {
     return "";
   }