From 7be3d1cbafa4434b05b8ae5b3ec2ba08a5edac9c Mon Sep 17 00:00:00 2001
From: Rafael Oleza <rafeca@fb.com>
Date: Fri, 2 Mar 2018 02:47:42 -0800
Subject: [PATCH] Make the chrome debugger handle dynamic delta ids

Differential Revision: D7112419

fbshipit-source-id: 1d80c0c13144dd19bbcd5535383befc6567cacf7
---
 .../server/util/debugger-ui/DeltaPatcher.js   |  8 +++++++
 .../util/debugger-ui/deltaUrlToBlobUrl.js     | 24 +++++++++----------
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/local-cli/server/util/debugger-ui/DeltaPatcher.js b/local-cli/server/util/debugger-ui/DeltaPatcher.js
index c137894942c51c..ecc92dce7b0ec1 100644
--- a/local-cli/server/util/debugger-ui/DeltaPatcher.js
+++ b/local-cli/server/util/debugger-ui/DeltaPatcher.js
@@ -30,6 +30,7 @@
         pre: new Map(),
         post: new Map(),
         modules: new Map(),
+        id: undefined,
       };
       this._initialized = false;
       this._lastNumModifiedFiles = 0;
@@ -66,6 +67,7 @@
           pre: new Map(),
           post: new Map(),
           modules: new Map(),
+          id: undefined,
         };
       }
 
@@ -80,9 +82,15 @@
       this._patchMap(this._lastBundle.post, deltaBundle.post);
       this._patchMap(this._lastBundle.modules, deltaBundle.delta);
 
+      this._lastBundle.id = deltaBundle.id;
+
       return this;
     }
 
+    getLastBundleId() {
+      return this._lastBundle.id;
+    }
+
     /**
      * Returns the number of modified files in the last received Delta. This is
      * currently used to populate the `X-Metro-Files-Changed-Count` HTTP header
diff --git a/local-cli/server/util/debugger-ui/deltaUrlToBlobUrl.js b/local-cli/server/util/debugger-ui/deltaUrlToBlobUrl.js
index afc1dd5caea3d6..d611062952aa22 100644
--- a/local-cli/server/util/debugger-ui/deltaUrlToBlobUrl.js
+++ b/local-cli/server/util/debugger-ui/deltaUrlToBlobUrl.js
@@ -20,31 +20,34 @@
    * whole JS bundle Blob.
    */
   async function deltaUrlToBlobUrl(deltaUrl) {
-    let cachedBundle = cachedBundleUrls.get(deltaUrl);
+    const client = global.DeltaPatcher.get(deltaUrl);
 
-    const deltaBundleId = cachedBundle
-      ? `&deltaBundleId=${cachedBundle.id}`
+    const deltaBundleId = client.getLastBundleId()
+      ? `&deltaBundleId=${client.getLastBundleId()}`
       : '';
 
     const data = await fetch(deltaUrl + deltaBundleId);
     const bundle = await data.json();
 
-    const deltaPatcher = global.DeltaPatcher.get(bundle.id).applyDelta({
+    const deltaPatcher = client.applyDelta({
+      id: bundle.id,
       pre: new Map(bundle.pre),
       post: new Map(bundle.post),
       delta: new Map(bundle.delta),
       reset: bundle.reset,
     });
 
+    let cachedBundle = cachedBundleUrls.get(deltaUrl);
+
     // If nothing changed, avoid recreating a bundle blob by reusing the
     // previous one.
     if (deltaPatcher.getLastNumModifiedFiles() === 0 && cachedBundle) {
-      return cachedBundle.url;
+      return cachedBundle;
     }
 
     // Clean up the previous bundle URL to not leak memory.
     if (cachedBundle) {
-      URL.revokeObjectURL(cachedBundle.url);
+      URL.revokeObjectURL(cachedBundle);
     }
 
     // To make Source Maps work correctly, we need to add a newline between
@@ -58,13 +61,10 @@
       type: 'application/javascript',
     });
 
-    const bundleUrl = URL.createObjectURL(blob);
-    cachedBundleUrls.set(deltaUrl, {
-      id: bundle.id,
-      url: bundleUrl,
-    });
+    const bundleContents = URL.createObjectURL(blob);
+    cachedBundleUrls.set(deltaUrl, bundleContents);
 
-    return bundleUrl;
+    return bundleContents;
   }
 
   global.deltaUrlToBlobUrl = deltaUrlToBlobUrl;