Fix check_remote task revision resolution

CHANGELOG.md

@@ -1,16 +1,17 @@
 # Changelog
 
 
-## v6.7.4
-[v6.7.3...v6.7.4](https://github.com/deployphp/deployer/compare/v6.7.3...v6.7.4)
+## master
+[v6.7.3...master](https://github.com/deployphp/deployer/compare/v6.7.3...master)
 
 ### Added
 - Documented check_remote task usage
 - Speedup deploy:clear_paths
 
 ### Fixed
-- Fixed Silverstripe CMS recipe assets path
-- Fixed check_remote task errors
+- Fixed Silverstripe CMS recipe assets path [#1989]
+- Fixed check_remote task errors [#1990]
+- Fixed check_remote task revision resolution [#1994]
 
 
 ## v6.7.3
@@ -557,6 +558,9 @@
 - Fixed remove of shared dir on first deploy
 
 
+[#1994]: https://github.com/deployphp/deployer/issues/1994
+[#1990]: https://github.com/deployphp/deployer/issues/1990
+[#1989]: https://github.com/deployphp/deployer/issues/1989
 [#1971]: https://github.com/deployphp/deployer/pull/1971
 [#1969]: https://github.com/deployphp/deployer/issues/1969
 [#1899]: https://github.com/deployphp/deployer/pull/1899

recipe/deploy/check_remote.php

@@ -7,29 +7,53 @@
 
 namespace Deployer;
 
+use Deployer\Exception\Exception;
 use Deployer\Exception\GracefulShutdownException;
 
-// Check and save the remote HEAD/revision and compare it with the existing saved one (if any).
-// This avoid unnecessary releases when the last commit id matches the existing one (HEAD).
+// Cancel deployment if there would be no change to the codebase.
+// This avoids unnecessary releases if the latest commit has already been deployed.
 desc('Check remote head');
 task('deploy:check_remote', function () {
     $repository = get('repository');
     if (empty($repository)) {
+        throw new Exception("You need to specify a repository.");
+    }
+
+    // Skip if there is no current deployment to compare
+    if (! test('[ -d {{deploy_path}}/current/.git ]')) {
         return;
     }
 
-    $revision = input()->getOption('revision') ?? null;
-    $remoteHead = $revision ?? runLocally(sprintf('%s ls-remote %s HEAD | tr -d "HEAD"', get('bin/git'), $repository));
+    // Determine the hash of the remote revision about to be deployed
+    $targetRevision = input()->getOption('revision');
+
+    if (!$targetRevision) {
+        $ref = 'HEAD';
+        $opt = '';
+
+        if ($tag = input()->getOption('tag')) {
+            $ref = $tag;
+            $opt = '--tags';
+        } elseif ($branch = get('branch')) {
+            $ref = $branch;
+            $opt = '--heads';
+        }
 
-    if (null == input()->getOption('tag')) {
-        // Init HEAD file if it doesn't exist, then compare
-        $headPath = get('deploy_path') . '/.dep/HEAD';
-        run("touch $headPath");
-        $headContents = run("cat $headPath");
-        if (trim($headContents) === trim($remoteHead)) {
-            throw new GracefulShutdownException("Already up-to-date.");
+        $remoteLs = runLocally(sprintf("%s ls-remote $opt $repository $ref", get('bin/git')));
+        if (strstr($remoteLs, "\n")) {
+            throw new Exception("Could not determine target revision. '$ref' matched multiple commits.");
+        }
+        if (!$remoteLs) {
+            throw new Exception("Could not resolve a revision from '$ref'.");
         }
+
+        $targetRevision = substr($remoteLs, 0, strpos($remoteLs, "\t"));
     }
 
-    run("cd {{deploy_path}} && echo $remoteHead > .dep/HEAD");
+    // Compare commit hashes. We use strpos to support short versions.
+    $targetRevision = trim($targetRevision);
+    $lastDeployedRevision = trim(run(sprintf('cd {{deploy_path}}/current && %s rev-parse HEAD', get('bin/git'))));
+    if ($targetRevision && strpos($lastDeployedRevision, $targetRevision) === 0) {
+        throw new GracefulShutdownException("Already up-to-date.");
+    }
 });