From a608ed496e7312cefbc8d2e585b843cf11428f2a Mon Sep 17 00:00:00 2001
From: Grzegorz Godlewski <gg@gitgis.com>
Date: Sat, 25 May 2024 20:40:26 +0200
Subject: [PATCH] Fix git behind indicator

Resolves: #419
---
 apps/ui/src/components/GitToolBar.vue |  4 ++--
 apps/ui/src/pages/GDocsView.vue       |  4 ++--
 src/git/GitScanner.ts                 | 23 ++++++++++++-----------
 3 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/apps/ui/src/components/GitToolBar.vue b/apps/ui/src/components/GitToolBar.vue
index 2ab3ba6c..2c243dcd 100644
--- a/apps/ui/src/components/GitToolBar.vue
+++ b/apps/ui/src/components/GitToolBar.vue
@@ -9,8 +9,8 @@
       <span class="badge" v-if="gitStats.headAhead > 0">
         {{ gitStats.headAhead }} commits ahead remote
       </span>
-      <span class="badge" v-if="gitStats.headAhead < 0">
-        {{ -gitStats.headAhead }} commits behind remote
+      <span class="badge" v-if="gitStats.headBehind > 0">
+        {{ gitStats.headBehind }} commits behind remote
       </span>
     </ToolButton>
 
diff --git a/apps/ui/src/pages/GDocsView.vue b/apps/ui/src/pages/GDocsView.vue
index fec91701..ccca8fed 100644
--- a/apps/ui/src/pages/GDocsView.vue
+++ b/apps/ui/src/pages/GDocsView.vue
@@ -169,8 +169,8 @@
                   <span class="badge" v-if="gitStats.headAhead > 0">
                     {{ gitStats.headAhead }} commits ahead remote
                   </span>
-              <span class="badge" v-if="gitStats.headAhead < 0">
-                    {{ -gitStats.headAhead }} commits behind remote
+                  <span class="badge" v-if="gitStats.headBehind > 0">
+                    {{ gitStats.headBehind }} commits behind remote
                   </span>
             </ToolButton>
 
diff --git a/src/git/GitScanner.ts b/src/git/GitScanner.ts
index a7289ae2..cefef44d 100644
--- a/src/git/GitScanner.ts
+++ b/src/git/GitScanner.ts
@@ -776,27 +776,27 @@ export class GitScanner {
     }
   }
 
-  async countAhead(remoteBranch: string) {
-    let retVal = 0;
-
+  async countAheadBehind(remoteBranch: string) {
     try {
-      const result = await this.exec(`git log origin/${remoteBranch}..HEAD`, {
+      const result = await this.exec(`git rev-list --left-right --count HEAD...origin/${remoteBranch}`, {
         skipLogger: true
       });
-      for (const line of result.stdout.split('\n')) {
-          if (line.startsWith('commit ')) {
-            retVal++;
-          }
-      }
+      const firstLine = result.stdout.split('\n')[0];
+
+      const [ ahead, behind ] = firstLine.split(/\s+/).map(val => parseInt(val));
+
+      return {
+        ahead, behind
+      };
       // eslint-disable-next-line no-empty
     } catch (ignore) {}
 
-    return retVal;
+    return { ahead: 0, behind: 0 };
   }
 
   async getStats(userConfig: UserConfig) {
     let initialized = true;
-    const headAhead = userConfig.remote_branch ? await this.countAhead(userConfig.remote_branch) : 0;
+    const { ahead: headAhead, behind: headBehind } = userConfig.remote_branch ? await this.countAheadBehind(userConfig.remote_branch) : { ahead: 0, behind: 0 };
     let unstaged = 0;
 
     try {
@@ -834,6 +834,7 @@ export class GitScanner {
     return {
       initialized,
       headAhead,
+      headBehind,
       unstaged,
       remote_branch: userConfig.remote_branch,
       remote_url: initialized ? await this.getRemoteUrl() : null