1585497 - Memoize inline preview per call stack item

Status: RESOLVED DUPLICATE of bug 1585515

(DevTools :: Debugger, enhancement, P1)

Description

[David Walsh :davidwalsh]

Consider: with inline preview on and the following change...

diff --git a/devtools/client/debugger/src/actions/pause/inlinePreview.js b/devtools/client/debugger/src/actions/pause/inlinePreview.js
--- a/devtools/client/debugger/src/actions/pause/inlinePreview.js
+++ b/devtools/client/debugger/src/actions/pause/inlinePreview.js
@@ -27,6 +27,9 @@ function getLocalScopeLevels(originalAst
 
 export function generateInlinePreview(cx: ThreadContext, frame: ?Frame) {
   return async function({ dispatch, getState, parser, client }: ThunkArgs) {
+
+    console.log("Getting inline previews!");
+
     if (!frame || !features.inlinePreview) {
       return;
     }
@@ -128,7 +131,6 @@ function getBindingValues(
   properties: Array<Object> | null
 ): Previews {
   const previews: Previews = {};
   const binding =
     originalAstScopes[curLevel] && originalAstScopes[curLevel].bindings[name];
   if (!binding) {

When paused, you can continually click the same function in the Call Stack panel and the inline preview is fetched over and over again.

We should try to memoize the result of generateInlinePreview to prevent the need for this.