fix(database): don't emit UNSIGNED on Postgres

packages/database/src/QueryStatements/IntegerStatement.php

@@ -29,14 +29,29 @@ public function compile(DatabaseDialect $dialect): string
                 $this->default !== null ? "DEFAULT {$this->default}" : '',
                 $this->nullable ? '' : 'NOT NULL',
             ),
-            default => sprintf(
+            // Postgres has no unsigned integer type, so omit the keyword there.
+            DatabaseDialect::POSTGRESQL => sprintf(
+                '%s %s %s %s',
+                $name,
+                $this->type(),
+                $this->default !== null ? "DEFAULT {$this->default}" : '',
+                $this->nullable ? '' : 'NOT NULL',
+            ),
+            DatabaseDialect::MYSQL => sprintf(
                 '%s %s %s %s %s',
                 $name,
-                is_int($this->size) ? DatabaseIntegerSize::fromBytes($this->size)->toString() : $this->size->toString(),
+                $this->type(),
                 $this->unsigned ? 'UNSIGNED' : '',
                 $this->default !== null ? "DEFAULT {$this->default}" : '',
                 $this->nullable ? '' : 'NOT NULL',
             ),
         };
     }
+
+    private function type(): string
+    {
+        return is_int($this->size)
+            ? DatabaseIntegerSize::fromBytes($this->size)->toString()
+            : $this->size->toString();
+    }
 }

packages/database/tests/QueryStatements/CreateTableStatementTest.php

@@ -113,7 +113,7 @@ public static function provide_fk_create_table_database_drivers(): Generator
             <<<SQL
             CREATE TABLE "books" (
                 "id" SERIAL PRIMARY KEY, 
-                "author_id" INTEGER  NOT NULL, 
+                "author_id" INTEGER NOT NULL, 
                 CONSTRAINT "fk_authors_books_author_id" FOREIGN KEY(author_id) REFERENCES authors(id) ON DELETE CASCADE ON UPDATE NO ACTION, 
                 "name" VARCHAR(255) NOT NULL
             );
@@ -165,7 +165,7 @@ public static function provide_fk_create_table_database_drivers_explicit(): Gene
             <<<SQL
             CREATE TABLE "books" (
                 "id" SERIAL PRIMARY KEY, 
-                "author_id" INTEGER  NOT NULL, 
+                "author_id" INTEGER NOT NULL, 
                 CONSTRAINT "fk_authors_books_author_id" FOREIGN KEY(author_id) REFERENCES authors(id) ON DELETE CASCADE ON UPDATE NO ACTION, 
                 "name" VARCHAR(255) NOT NULL
             );

tests/Integration/Database/QueryStatements/IntegerStatementTest.php

@@ -0,0 +1,89 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Tests\Tempest\Integration\Database\QueryStatements;
+
+use PHPUnit\Framework\Attributes\Test;
+use Tempest\Database\Config\DatabaseDialect;
+use Tempest\Database\MigratesUp;
+use Tempest\Database\Migrations\CreateMigrationsTable;
+use Tempest\Database\QueryStatement;
+use Tempest\Database\QueryStatements\CreateTableStatement;
+use Tempest\Database\QueryStatements\DatabaseIntegerSize;
+use Tempest\Database\QueryStatements\IntegerStatement;
+use Tests\Tempest\Integration\FrameworkIntegrationTestCase;
+
+/**
+ * @internal
+ */
+final class IntegerStatementTest extends FrameworkIntegrationTestCase
+{
+    #[Test]
+    public function unsigned_columns_are_created_on_whichever_database_is_configured(): void
+    {
+        $migration = new class() implements MigratesUp {
+            private(set) string $name = '0000_create_unsigned_integers_table';
+
+            public function up(): QueryStatement
+            {
+                return new CreateTableStatement('unsigned_integers')
+                    ->primary()
+                    ->integer('small', unsigned: true, size: DatabaseIntegerSize::SMALL)
+                    ->integer('regular', unsigned: true)
+                    ->integer('big', unsigned: true, size: DatabaseIntegerSize::BIG)
+                    ->integer('nullable_with_default', unsigned: true, nullable: true, default: 1);
+            }
+        };
+
+        $this->database->migrate(CreateMigrationsTable::class, $migration);
+
+        $this->expectNotToPerformAssertions();
+    }
+
+    #[Test]
+    public function postgres_is_not_told_about_a_keyword_it_does_not_have(): void
+    {
+        $statement = new IntegerStatement('votes', unsigned: true)->compile(DatabaseDialect::POSTGRESQL);
+
+        $this->assertStringNotContainsString('UNSIGNED', $statement);
+        $this->assertStringContainsString('INTEGER', $statement);
+    }
+
+    #[Test]
+    public function mysql_keeps_its_unsigned_range(): void
+    {
+        // MySQL supports `UNSIGNED`; dropping it globally would silently halve the requested range.
+        $this->assertStringContainsString(
+            'UNSIGNED',
+            new IntegerStatement('votes', unsigned: true)->compile(DatabaseDialect::MYSQL),
+        );
+
+        $this->assertStringNotContainsString(
+            'UNSIGNED',
+            new IntegerStatement('votes')->compile(DatabaseDialect::MYSQL),
+        );
+    }
+
+    #[Test]
+    public function the_size_chooses_the_type(): void
+    {
+        foreach ([DatabaseDialect::MYSQL, DatabaseDialect::POSTGRESQL] as $dialect) {
+            $this->assertStringContainsString(
+                'SMALLINT',
+                new IntegerStatement('n', size: DatabaseIntegerSize::SMALL)->compile($dialect),
+            );
+
+            $this->assertStringContainsString(
+                'BIGINT',
+                new IntegerStatement('n', size: DatabaseIntegerSize::BIG)->compile($dialect),
+            );
+
+            // A byte count is rounded up to the size that can hold it.
+            $this->assertStringContainsString(
+                'BIGINT',
+                new IntegerStatement('n', size: 8)->compile($dialect),
+            );
+        }
+    }
+}