From f344cf617e3b46ac1a5bdb3fa8714c255b47a450 Mon Sep 17 00:00:00 2001
From: James Titcumb <james@asgrim.com>
Date: Thu, 10 Oct 2019 11:41:19 +0100
Subject: [PATCH] Support setting git_sha with HEROKU_SLUG_COMMIT environment
 variable

---
 src/Events/Metadata.php            |  6 ++++++
 tests/Unit/Events/MetadataTest.php | 20 ++++++++++++++++++++
 2 files changed, 26 insertions(+)

diff --git a/src/Events/Metadata.php b/src/Events/Metadata.php
index 1f5e23a3..f7044ba4 100644
--- a/src/Events/Metadata.php
+++ b/src/Events/Metadata.php
@@ -17,6 +17,7 @@
 use function dirname;
 use function explode;
 use function file_exists;
+use function getenv;
 use function gethostname;
 use function is_readable;
 use function is_string;
@@ -124,6 +125,11 @@ private function rootPackageGitSha() : string
             return $revisionShaConfiguration;
         }
 
+        $herokuSlugCommit = getenv('HEROKU_SLUG_COMMIT');
+        if (is_string($herokuSlugCommit) && $herokuSlugCommit !== '') {
+            return $herokuSlugCommit;
+        }
+
         return explode('@', Versions::getVersion(Versions::ROOT_PACKAGE_NAME))[1];
     }
 
diff --git a/tests/Unit/Events/MetadataTest.php b/tests/Unit/Events/MetadataTest.php
index 6b9cd65e..a8814b7f 100644
--- a/tests/Unit/Events/MetadataTest.php
+++ b/tests/Unit/Events/MetadataTest.php
@@ -20,6 +20,8 @@
 use function gethostname;
 use function json_decode;
 use function json_encode;
+use function putenv;
+use function uniqid;
 
 /** @covers \Scoutapm\Events\Metadata */
 final class MetadataTest extends TestCase
@@ -117,4 +119,22 @@ static function ($package, $version) {
             json_decode(json_encode(new Metadata($time, $config)), true)
         );
     }
+
+    /** @throws Exception */
+    public function testHerokuSlugCommitOverridesTheGitSha() : void
+    {
+        $testHerokuSlugCommit = uniqid('testHerokuSlugCommit', true);
+
+        putenv('HEROKU_SLUG_COMMIT=' . $testHerokuSlugCommit);
+
+        self::assertSame(
+            $testHerokuSlugCommit,
+            json_decode(json_encode(new Metadata(
+                new DateTimeImmutable('now', new DateTimeZone('UTC')),
+                Config::fromArray([])
+            )), true)['ApplicationEvent']['event_value']['git_sha']
+        );
+
+        putenv('HEROKU_SLUG_COMMIT');
+    }
 }