Use new column definition builder

src/Column.php

@@ -21,6 +21,10 @@
  *
  * Provides a fluent interface, which means that the methods can be chained together to create a column schema with
  * many properties in a single line of code.
+ *
+ * @psalm-suppress DeprecatedClass
+ *
+ * @deprecated Use {@see StringColumnSchema} or other column classes instead. Will be removed in 2.0.0.
  */
 final class Column extends AbstractColumn
 {

src/Column/ColumnDefinitionBuilder.php

@@ -47,6 +47,12 @@ public function build(ColumnSchemaInterface $column): string
             . $this->buildExtra($column);
     }
 
+    public function buildAlter(ColumnSchemaInterface $column): string
+    {
+        return $this->buildType($column)
+            . $this->buildExtra($column);
+    }
+
     protected function buildType(ColumnSchemaInterface $column): string
     {
         if ($column instanceof \Yiisoft\Db\Schema\Column\ArrayColumnSchema) {

src/DDLQueryBuilder.php

@@ -8,11 +8,12 @@
 use Yiisoft\Db\Exception\NotSupportedException;
 use Yiisoft\Db\QueryBuilder\AbstractDDLQueryBuilder;
 use Yiisoft\Db\Schema\Builder\ColumnInterface;
+use Yiisoft\Db\Schema\Column\ColumnSchemaInterface;
 
 use function array_diff;
-use function array_unshift;
 use function explode;
 use function implode;
+use function is_string;
 use function preg_match;
 use function preg_replace;
 use function str_contains;
@@ -27,7 +28,7 @@ public function addDefaultValue(string $table, string $name, string $column, mix
         throw new NotSupportedException(__METHOD__ . ' is not supported by PostgreSQL.');
     }
 
-    public function alterColumn(string $table, string $column, ColumnInterface|string $type): string
+    public function alterColumn(string $table, string $column, ColumnInterface|ColumnSchemaInterface|string $type): string
     {
         $columnName = $this->quoter->quoteColumnName($column);
         $tableName = $this->quoter->quoteTableName($table);
@@ -40,47 +41,42 @@ public function alterColumn(string $table, string $column, ColumnInterface|strin
          * @link https://github.com/yiisoft/yii2/issues/4492
          * @link https://www.postgresql.org/docs/9.1/static/sql-altertable.html
          */
-        if (preg_match('/^(DROP|SET|RESET|USING)\s+/i', $type)) {
-            return "ALTER TABLE $tableName ALTER COLUMN $columnName $type";
+        if (is_string($type)) {
+            if (preg_match('/^(DROP|SET|RESET|USING)\s+/i', $type) === 1) {
+                return "ALTER TABLE $tableName ALTER COLUMN $columnName $type";
+            }
+
+            $type = $this->schema->getColumnFactory()->fromDefinition($type);
         }
 
-        /** @psalm-suppress DeprecatedMethod */
-        $type = 'TYPE ' . $this->queryBuilder->getColumnType($type);
-        $multiAlterStatement = [];
-        $constraintPrefix = preg_replace('/[^a-z0-9_]/i', '', $table . '_' . $column);
+        $columnDefinitionBuilder = $this->queryBuilder->getColumnDefinitionBuilder();
 
-        if (preg_match('/\s+DEFAULT\s+(["\']?\w*["\']?)/i', $type, $matches)) {
-            $type = preg_replace('/\s+DEFAULT\s+(["\']?\w*["\']?)/i', '', $type);
-            $multiAlterStatement[] = "ALTER COLUMN $columnName SET DEFAULT $matches[1]";
-        }
+        $multiAlterStatement = ["ALTER COLUMN $columnName TYPE " . $columnDefinitionBuilder->buildAlter($type)];
 
-        $type = preg_replace('/\s+NOT\s+NULL/i', '', $type, -1, $count);
+        if ($type->hasDefaultValue()) {
+            $defaultValue = $type->dbTypecast($type->getDefaultValue());
+            $defaultValue = $this->queryBuilder->prepareValue($defaultValue);
 
-        if ($count > 0) {
-            $multiAlterStatement[] = "ALTER COLUMN $columnName SET NOT NULL";
-        } else {
-            /** remove extra null if any */
-            $type = preg_replace('/\s+NULL/i', '', $type, -1, $count);
-            if ($count > 0) {
-                $multiAlterStatement[] = "ALTER COLUMN $columnName DROP NOT NULL";
-            }
+            $multiAlterStatement[] = "ALTER COLUMN $columnName SET DEFAULT $defaultValue";
         }
 
-        if (preg_match('/\s+CHECK\s+\((.+)\)/i', $type, $matches)) {
-            $type = preg_replace('/\s+CHECK\s+\((.+)\)/i', '', $type);
-            $multiAlterStatement[] = "ADD CONSTRAINT {$constraintPrefix}_check CHECK ($matches[1])";
-        }
+        match ($type->isNotNull()) {
+            true => $multiAlterStatement[] = "ALTER COLUMN $columnName SET NOT NULL",
+            false => $multiAlterStatement[] = "ALTER COLUMN $columnName DROP NOT NULL",
+            default => null,
+        };
 
-        $type = preg_replace('/\s+UNIQUE/i', '', $type, -1, $count);
+        $check = $type->getCheck();
+        if (!empty($check)) {
+            $constraintPrefix = preg_replace('/\W/', '', $table . '_' . $column);
+            $multiAlterStatement[] = "ADD CONSTRAINT {$constraintPrefix}_check CHECK ($check)";
+        }
 
-        if ($count > 0) {
+        if ($type->isUnique()) {
             $multiAlterStatement[] = "ADD UNIQUE ($columnName)";
         }
 
-        /** add what's left at the beginning */
-        array_unshift($multiAlterStatement, "ALTER COLUMN $columnName $type");
-
-        return 'ALTER TABLE ' . $tableName . ' ' . implode(', ', $multiAlterStatement);
+        return "ALTER TABLE $tableName " . implode(', ', $multiAlterStatement);
     }
 
     /**

src/Schema.php

@@ -103,6 +103,7 @@ final class Schema extends AbstractPdoSchema
     /** @deprecated Use {@see ColumnBuilder} instead. Will be removed in 2.0. */
     public function createColumn(string $type, array|int|string $length = null): ColumnInterface
     {
+        /** @psalm-suppress DeprecatedClass */
         return new Column($type, $length);
     }
 

tests/Provider/QueryBuilderProvider.php

@@ -23,6 +23,37 @@ final class QueryBuilderProvider extends \Yiisoft\Db\Tests\Provider\QueryBuilder
 
     protected static string $driverName = 'pgsql';
 
+    public static function alterColumn(): array
+    {
+        return [
+            ['SET NOT null', 'ALTER TABLE "foo1" ALTER COLUMN "bar" SET NOT null'],
+            ['drop default', 'ALTER TABLE "foo1" ALTER COLUMN "bar" drop default'],
+            ['reset xyz', 'ALTER TABLE "foo1" ALTER COLUMN "bar" reset xyz'],
+            ['string', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255)'],
+            ['varchar(255)', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255)'],
+            ['string NOT NULL', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET NOT NULL'],
+            ['string NULL', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" DROP NOT NULL'],
+            ['string DEFAULT NULL', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET DEFAULT NULL'],
+            ["string DEFAULT ''", 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET DEFAULT \'\''],
+            ['timestamp(0) DEFAULT now()', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE timestamp(0), ALTER COLUMN "bar" SET DEFAULT now()'],
+            ['string CHECK (char_length(bar) > 5)', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ADD CONSTRAINT foo1_bar_check CHECK (char_length(bar) > 5)'],
+            ['string(30) UNIQUE', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(30), ADD UNIQUE ("bar")'],
+            ['varchar(255) USING bar::varchar', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255) USING bar::varchar'],
+            ['varchar(255) using cast("bar" as varchar)', 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255) using cast("bar" as varchar)'],
+            [ColumnBuilder::string(), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255)'],
+            [ColumnBuilder::string()->notNull(), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET NOT NULL'],
+            [ColumnBuilder::string()->null(), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" DROP NOT NULL'],
+            [ColumnBuilder::string()->defaultValue(null), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET DEFAULT NULL'],
+            [ColumnBuilder::string()->defaultValue(''), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET DEFAULT \'\''],
+            [ColumnBuilder::string()->null()->defaultValue('xxx'), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ALTER COLUMN "bar" SET DEFAULT \'xxx\', ALTER COLUMN "bar" DROP NOT NULL'],
+            [ColumnBuilder::timestamp()->defaultValue(new Expression('now()')), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE timestamp(0), ALTER COLUMN "bar" SET DEFAULT now()'],
+            [ColumnBuilder::string()->check('char_length(bar) > 5'), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255), ADD CONSTRAINT foo1_bar_check CHECK (char_length(bar) > 5)'],
+            [ColumnBuilder::string(30)->unique(), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(30), ADD UNIQUE ("bar")'],
+            [ColumnBuilder::string()->extra('USING bar::varchar'), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255) USING bar::varchar'],
+            [ColumnBuilder::string()->extra('using cast("bar" as varchar)'), 'ALTER TABLE "foo1" ALTER COLUMN "bar" TYPE varchar(255) using cast("bar" as varchar)'],
+        ];
+    }
+
     public static function buildCondition(): array
     {
         $buildCondition = parent::buildCondition();