fix: quote namespace names

src/Platforms/AbstractPlatform.php

@@ -55,6 +55,7 @@
 use function key;
 use function max;
 use function mb_strlen;
+use function preg_match;
 use function preg_quote;
 use function preg_replace;
 use function sprintf;
@@ -1038,6 +1039,10 @@ public function getAlterSchemaSQL(SchemaDiff $diff): array
             foreach ($diff->getCreatedSchemas() as $schema) {
                 $sql[] = $this->getCreateSchemaSQL($schema);
             }
+
+            foreach ($diff->getDroppedSchemas() as $schema) {
+                $sql[] = $this->getDropSchemaSQL($schema);
+            }
         }
 
         if ($this->supportsSequences()) {
@@ -1162,6 +1167,10 @@ public function getCreateSchemaSQL(string $schemaName): string
             throw NotSupported::new(__METHOD__);
         }
 
+        if (preg_match('/^\d/', $schemaName) > 0) {
+            return 'CREATE SCHEMA ' . $this->quoteIdentifier($schemaName);
+        }
+
         return 'CREATE SCHEMA ' . $schemaName;
     }
 
@@ -1183,6 +1192,10 @@ public function getDropSchemaSQL(string $schemaName): string
             throw NotSupported::new(__METHOD__);
         }
 
+        if (preg_match('/^\d/', $schemaName) > 0) {
+            return 'DROP SCHEMA ' . $this->quoteIdentifier($schemaName);
+        }
+
         return 'DROP SCHEMA ' . $schemaName;
     }
 

src/Schema/AbstractAsset.php

@@ -11,6 +11,7 @@
 use function dechex;
 use function explode;
 use function implode;
+use function preg_match;
 use function str_contains;
 use function str_replace;
 use function strtolower;
@@ -131,7 +132,9 @@ public function getQuotedName(AbstractPlatform $platform): string
         $keywords = $platform->getReservedKeywordsList();
         $parts    = explode('.', $this->getName());
         foreach ($parts as $k => $v) {
-            $parts[$k] = $this->_quoted || $keywords->isKeyword($v) ? $platform->quoteIdentifier($v) : $v;
+            $shouldBeQuoted = $this->_quoted || $keywords->isKeyword($v) || preg_match('/^\d/', $v) !== 0;
+
+            $parts[$k] = $shouldBeQuoted ? $platform->quoteIdentifier($v) : $v;
         }
 
         return implode('.', $parts);

src/Schema/Exception/NamespaceDoesNotExist.php

@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Doctrine\DBAL\Schema\Exception;
+
+use Doctrine\DBAL\Schema\SchemaException;
+use LogicException;
+
+use function sprintf;
+
+/** @psalm-immutable */
+final class NamespaceDoesNotExist extends LogicException implements SchemaException
+{
+    public static function new(string $namespaceName): self
+    {
+        return new self(sprintf('There is no namespace with name "%s" in the schema.', $namespaceName));
+    }
+}

src/Schema/Schema.php

@@ -7,6 +7,7 @@
 use Doctrine\DBAL\Exception;
 use Doctrine\DBAL\Platforms\AbstractPlatform;
 use Doctrine\DBAL\Schema\Exception\NamespaceAlreadyExists;
+use Doctrine\DBAL\Schema\Exception\NamespaceDoesNotExist;
 use Doctrine\DBAL\Schema\Exception\SequenceAlreadyExists;
 use Doctrine\DBAL\Schema\Exception\SequenceDoesNotExist;
 use Doctrine\DBAL\Schema\Exception\TableAlreadyExists;
@@ -267,6 +268,24 @@ public function createNamespace(string $name): self
         return $this;
     }
 
+    /**
+     * Drops a new namespace from the schema.
+     *
+     * @return $this
+     */
+    public function dropNamespace(string $name): self
+    {
+        $unquotedName = strtolower($this->getUnquotedAssetName($name));
+
+        if (! isset($this->namespaces[$unquotedName])) {
+            throw NamespaceDoesNotExist::new($unquotedName);
+        }
+
+        unset($this->namespaces[$unquotedName]);
+
+        return $this;
+    }
+
     /**
      * Creates a new table.
      */

tests/Functional/Schema/PostgreSQLSchemaManagerTest.php

@@ -336,12 +336,10 @@ protected function assertVarBinaryColumnIsValid(Table $table, string $columnName
     /**
      * Although this test would pass in isolation on any platform, we keep it here for the following reasons:
      *
-     * 1. The DBAL currently doesn't properly drop tables in the namespaces that need to be quoted
-     *    (@see testListTableDetailsWhenCurrentSchemaNameQuoted()).
-     * 2. The schema returned by {@see AbstractSchemaManager::introspectSchema()} doesn't contain views, so
+     * 1. The schema returned by {@see AbstractSchemaManager::introspectSchema()} doesn't contain views, so
      *    {@see AbstractSchemaManager::dropSchemaObjects()} cannot drop the tables that have dependent views
      *    (@see testListTablesExcludesViews()).
-     * 3. In the case of inheritance, PHPUnit runs the tests declared immediately in the test class
+     * 2. In the case of inheritance, PHPUnit runs the tests declared immediately in the test class
      *    and then runs the tests declared in the parent.
      *
      * This test needs to be executed before the ones it conflicts with, so it has to be declared in the same class.

tests/Functional/Schema/SchemaManagerFunctionalTestCase.php

@@ -1419,6 +1419,53 @@ public function testDropColumnWithDefault(): void
         self::assertCount(1, $columns);
     }
 
+    public function testCanCreateAndDropSchemaThatNeedToBeQuoted(): void
+    {
+        $platform = $this->connection->getDatabasePlatform();
+
+        if (! $platform->supportsSchemas()) {
+            self::markTestSkipped('The platform does not support schema/namespaces.');
+        }
+
+        $schemaManager = $this->connection->createSchemaManager();
+        $schema        = $schemaManager->introspectSchema();
+
+        $schema->createNamespace('001_schema');
+
+        $schemaManager = $this->connection->createSchemaManager();
+        $schemaManager->migrateSchema($schema);
+        self::assertContains('001_schema', $schemaManager->listSchemaNames());
+
+        $schema->dropNamespace('001_schema');
+        $schemaManager->migrateSchema($schema);
+        self::assertNotContains('001_schema', $schemaManager->listSchemaNames());
+    }
+
+    public function testCanCreateAndDropTableFromNamespaceThatNeedToBeQuoted(): void
+    {
+        $platform = $this->connection->getDatabasePlatform();
+
+        if (! $platform->supportsSchemas()) {
+            self::markTestSkipped('The platform does not support schema/namespaces.');
+        }
+
+        $schemaManager = $this->connection->createSchemaManager();
+        $schema        = $schemaManager->introspectSchema();
+
+        $table = $schema->createTable('001_schema.test_quoted_schema');
+        $table->addColumn('id', Types::INTEGER, ['notnull' => true]);
+        $table->setPrimaryKey(['id']);
+
+        $schemaManager = $this->connection->createSchemaManager();
+        $schemaManager->migrateSchema($schema);
+        self::assertContains('001_schema', $schemaManager->listSchemaNames());
+        self::assertContains('001_schema.test_quoted_schema', $schemaManager->listTableNames());
+
+        $schema->dropTable('001_schema.test_quoted_schema');
+        $schemaManager->migrateSchema($schema);
+        self::assertNotContains('001_schema.test_quoted_schema', $schemaManager->listTableNames());
+    }
+
     /** @param list<Table> $tables */
     protected function findTableByName(array $tables, string $name): ?Table
     {