From a7e8b97e20f32154bf5bc0fedca2df9d060ccede Mon Sep 17 00:00:00 2001
From: Anukul Sangwan <anukulsangwan@icloud.com>
Date: Wed, 27 Sep 2023 23:51:22 +0400
Subject: [PATCH 1/2] preload PR coverage report

---
 src/content/github/common/fetchers.ts |  4 +++-
 src/content/github/pr/main.tsx        | 10 +++++++++-
 src/service.ts                        | 27 ++++++++++++++++++---------
 3 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/src/content/github/common/fetchers.ts b/src/content/github/common/fetchers.ts
index 1759efa..e8f3983 100644
--- a/src/content/github/common/fetchers.ts
+++ b/src/content/github/common/fetchers.ts
@@ -106,6 +106,7 @@ export async function getPRReport(url: any) {
     owner: url.owner,
     repo: url.repo,
     pullid: url.id,
+    isDiff: url.isDiff,
   };
 
   const response = await browser.runtime.sendMessage({
@@ -114,5 +115,6 @@ export async function getPRReport(url: any) {
     referrer: window.location.href,
   });
 
-  return response.data;
+  // does not await response when called with isDiff: false
+  return response?.data || {};
 }
diff --git a/src/content/github/pr/main.tsx b/src/content/github/pr/main.tsx
index c80f16c..d8bebab 100644
--- a/src/content/github/pr/main.tsx
+++ b/src/content/github/pr/main.tsx
@@ -32,6 +32,13 @@ async function execute() {
     return;
   }
 
+  if (!urlMetadata.isDiff) {
+    // if not on diff view, dispatch API request
+    // promise will be resolved when needed
+    getPRReport(urlMetadata);
+    return;
+  }
+
   createContainer();
 
   const coverageReport = await getPRReport(urlMetadata);
@@ -64,7 +71,8 @@ function createContainer() {
 }
 
 function getMetadataFromURL(): { [key: string]: string } | null {
-  const regexp = /\/(?<owner>.+?)\/(?<repo>.+?)\/pull\/(?<id>\d+?)\/files/;
+  const regexp =
+    /\/(?<owner>.+?)\/(?<repo>.+?)\/pull\/(?<id>\d+)(\/(?<isDiff>files))?/;
   const matches = regexp.exec(window.location.pathname);
   const groups = matches?.groups;
   if (!groups) {
diff --git a/src/service.ts b/src/service.ts
index 594f516..902099e 100644
--- a/src/service.ts
+++ b/src/service.ts
@@ -13,6 +13,7 @@ import {
 export class Codecov {
   static baseUrl = "https://api.codecov.io";
   static checkAuthPath = "/api/v2/github/codecov";
+  static cache: { [pullUrl: string]: any } = {};
 
   static _init() {
     fetchIntercept.register({
@@ -104,7 +105,7 @@ export class Codecov {
   }
 
   static async fetchPRComparison(payload: any, referrer: string): Promise<any> {
-    const { service, owner, repo, pullid } = payload;
+    const { service, owner, repo, pullid, isDiff } = payload;
 
     const url = new URL(
       `/api/v2/${service}/${owner}/repos/${repo}/compare`,
@@ -113,16 +114,24 @@ export class Codecov {
     const params = { pullid };
     url.search = new URLSearchParams(params).toString();
 
-    const response = await fetch(url.toString(), {
-      headers: {
-        Referrer: referrer,
-      },
-    });
-    const data = await response.json();
-
+    let response = await Promise.resolve(this.cache[url.toString()]);
+    if (!response?.ok) {
+      this.cache[url.toString()] = fetch(url.toString(), {
+        headers: {
+          Referrer: referrer,
+        },
+      });
+    }
+
+    if (!isDiff) {
+      return;
+    }
+
+    // await promise immediately if requested from diff view
+    response = await Promise.resolve(this.cache[url.toString()]);
     return {
       ok: response.ok,
-      data,
+      data: await response.clone().json(),
     };
   }
 

From e636e09b7ab5b744b8c965340e67fb111afa6099 Mon Sep 17 00:00:00 2001
From: Anukul Sangwan <anukulsangwan@icloud.com>
Date: Thu, 28 Sep 2023 01:25:05 +0400
Subject: [PATCH 2/2] nit

---
 src/content/github/pr/main.tsx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/content/github/pr/main.tsx b/src/content/github/pr/main.tsx
index d8bebab..06d4212 100644
--- a/src/content/github/pr/main.tsx
+++ b/src/content/github/pr/main.tsx
@@ -35,7 +35,7 @@ async function execute() {
   if (!urlMetadata.isDiff) {
     // if not on diff view, dispatch API request
     // promise will be resolved when needed
-    getPRReport(urlMetadata);
+    await getPRReport(urlMetadata);
     return;
   }