From 6ad6fa64258491fb35f9306c04ca2740bb4f6040 Mon Sep 17 00:00:00 2001
From: Maxence Lange <maxence@artificial-owl.com>
Date: Tue, 6 Aug 2024 22:22:38 -0100
Subject: [PATCH] fix(migration-preview): display a message if no attributes
 set

Signed-off-by: Maxence Lange <maxence@artificial-owl.com>
---
 core/Command/Db/Migrations/PreviewCommand.php |  9 +++++++++
 lib/private/Migration/MetadataManager.php     | 12 ++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/core/Command/Db/Migrations/PreviewCommand.php b/core/Command/Db/Migrations/PreviewCommand.php
index e35100dacb2..5a0e766ee6d 100644
--- a/core/Command/Db/Migrations/PreviewCommand.php
+++ b/core/Command/Db/Migrations/PreviewCommand.php
@@ -62,6 +62,12 @@ class PreviewCommand extends Command {
 		}
 		$table->render();
 
+		$unsupportedApps = $this->metadataManager->getUnsupportedApps($metadata['migrations']);
+		if (!empty($unsupportedApps)) {
+			$output->writeln('');
+			$output->writeln('Those apps are not supporting metadata yet and might initiate migrations on upgrade: <info>' . implode(', ', $unsupportedApps) . '</info>');
+		}
+
 		return 0;
 	}
 
@@ -90,6 +96,9 @@ class PreviewCommand extends Command {
 		/** @var MigrationAttribute[] $attributes */
 		foreach($data as $migration => $attributes) {
 			$attributesStr = [];
+			if (empty($attributes)) {
+				$attributesStr[] = '<comment>(metadata not set)</comment>';
+			}
 			foreach($attributes as $attribute) {
 				$definition = '<info>' . $attribute->definition() . "</info>";
 				$definition .= empty($attribute->getDescription()) ? '' : "\n  " . $attribute->getDescription();
diff --git a/lib/private/Migration/MetadataManager.php b/lib/private/Migration/MetadataManager.php
index 402252d6a46..324c169c626 100644
--- a/lib/private/Migration/MetadataManager.php
+++ b/lib/private/Migration/MetadataManager.php
@@ -88,6 +88,18 @@ class MetadataManager {
 		];
 	}
 
+	/**
+	 * returns list of installed apps that does not support migrations metadata (yet)
+	 *
+	 * @param array<array-key, array<array-key, array>> $metadata
+	 *
+	 * @return string[]
+	 * @since 30.0.0
+	 */
+	public function getUnsupportedApps(array $metadata): array {
+		return array_values(array_diff($this->appManager->getInstalledApps(), array_keys($metadata['apps'])));
+	}
+
 	/**
 	 * convert raw data to a list of MigrationAttribute
 	 *
-- 
2.39.5