[Enhance] Add support for renaming columns via the change clause.

README.md

@@ -15,3 +15,4 @@ $ composer require tithely/exo
 ## Documentation
 - [Introduction](doc/01-introduction.md)
 - [Usage](doc/02-usage.md)
+- [Testing](doc/03-testing.md)

src/ExecMigration.php

@@ -33,7 +33,7 @@ public static function create(string $name): ExecMigration
      * @param string      $name
      * @param string|null $body
      */
-    private function __construct(string $name, string $body = null)
+    private function __construct(string $name, ?string $body = null)
     {
         $this->name = $name;
         $this->body = $body;

src/FunctionMigration.php

@@ -104,13 +104,13 @@ public static function drop(string $name): FunctionMigration
     private function __construct(
         string $name,
         string $operation,
-        ReturnTypeOperation $returnType = null,
+        ?ReturnTypeOperation $returnType = null,
         bool $deterministic = false,
         string $dataUse = 'READS SQL DATA',
         string $language = 'plpgsql',
         array $parameterOperations = [],
         array $variableOperations = [],
-        string $body = null
+        ?string $body = null
     ) {
         $this->name = $name;
         $this->operation = $operation;

src/History.php

@@ -64,7 +64,7 @@ public function add(string $version, MigrationInterface $migrationOrView)
      * @param array|null $versions
      * @return History
      */
-    public function clone(array $versions = null): History
+    public function clone(?array $versions = null): History
     {
         $history = new History();
 

src/Operation/ColumnOperation.php

@@ -6,13 +6,24 @@ final class ColumnOperation extends AbstractOperation
 {
     const ADD = 'add';
     const MODIFY = 'modify';
+    const CHANGE = 'change';
     const DROP = 'drop';
 
     /**
      * @var string
      */
     private string $operation;
 
+    /**
+     * @var string
+     */
+    private string $beforeName;
+
+    /**
+     * @var string
+     */
+    private string $afterName;
+
     /**
      * @var array
      */
@@ -30,6 +41,14 @@ public function __construct(string $name, string $operation, array $options)
         $this->name = $name;
         $this->operation = $operation;
         $this->options = $options;
+
+        if ($operation === self::CHANGE && isset($options['new_name'])) {
+            $this->beforeName = $name;
+            $this->afterName = $options['new_name'];
+        } else {
+            $this->beforeName = $name;
+            $this->afterName = $name;
+        }
     }
 
     /**
@@ -51,4 +70,24 @@ public function getOptions(): array
     {
         return $this->options;
     }
+
+    /**
+     * Returns the before name (original name for CHANGE operations).
+     *
+     * @return string
+     */
+    public function getBeforeName(): string
+    {
+        return $this->beforeName;
+    }
+
+    /**
+     * Returns the after name (new name for CHANGE operations).
+     *
+     * @return string
+     */
+    public function getAfterName(): string
+    {
+        return $this->afterName;
+    }
 }

src/Operation/ExecOperation.php

@@ -15,7 +15,7 @@ final class ExecOperation extends AbstractOperation
      * @param string   $name
      * @param ?string   $body
      */
-    public function __construct(string $name, string $body = null) {
+    public function __construct(string $name, ?string $body = null) {
         $this->name = $name;
         $this->body = $body;
     }

src/Operation/FunctionOperation.php

@@ -66,13 +66,13 @@ final class FunctionOperation extends AbstractOperation implements ReversibleOpe
     public function __construct(
         string $name,
         string $operation,
-        ReturnTypeOperation $returnType = null,
+        ?ReturnTypeOperation $returnType = null,
         bool $deterministic = false,
         string $dataUse = 'READS SQL DATA',
         string $language = 'plpgsql',
         array $parameterOperations = [],
         array $variableOperations = [],
-        string $body = null
+        ?string $body = null
     ) {
         $this->name = $name;
         $this->operation = $operation;

src/Operation/ProcedureOperation.php

@@ -64,7 +64,7 @@ public function __construct(
         string $language = 'plpgsql',
         array $inParameterOperations = [],
         array $outParameterOperations = [],
-        string $body = null
+        ?string $body = null
     ) {
         $this->name = $name;
         $this->operation = $operation;

src/Operation/TableOperation.php

@@ -93,16 +93,26 @@ public function reverse(?ReversibleOperationInterface $originalOperation = null)
                 $columnOperations[] = $originalColumn;
             }
 
-            if ($columnOperation->getOperation() === ColumnOperation::MODIFY) {
+            if ($columnOperation->getOperation() === ColumnOperation::MODIFY || $columnOperation->getOperation() === ColumnOperation::CHANGE) {
                 if (!$originalColumn) {
                     throw new LogicException('Cannot revert a column that does not exist.');
                 }
 
-                $columnOperations[] = new ColumnOperation(
-                    $columnOperation->getName(),
-                    ColumnOperation::MODIFY,
-                    $originalColumn->getOptions()
-                );
+                if ($columnOperation->getOperation() === ColumnOperation::MODIFY) {
+                    $columnOperations[] = new ColumnOperation(
+                        $columnOperation->getName(),
+                        $columnOperation->getOperation(),
+                        $originalColumn->getOptions()
+                    );
+                } else {
+                    $options = $originalColumn->getOptions();
+                    $options['new_name'] = $columnOperation->getBeforeName();
+                    $columnOperations[] = new ColumnOperation(
+                        $columnOperation->getAfterName(),
+                        $columnOperation->getOperation(),
+                        $options
+                    );
+                }
             }
         }
 
@@ -192,7 +202,7 @@ public function apply(ReducibleOperationInterface $operation): ?ReducibleOperati
                     $offset = array_search($options['after'], array_keys($columns)) + 1;
                 }
 
-                // Remove existing operation for the column
+                // Remove existing operation for the column using proper name matching
                 foreach ($columns as $existing => $column) {
                     if ($column->getName() === $columnOperation->getName()) {
                         unset($columns[$existing]);
@@ -213,6 +223,15 @@ public function apply(ReducibleOperationInterface $operation): ?ReducibleOperati
                             $options
                         );
 
+                        array_splice($columns, $offset, 0, [$addOperation]);
+                        break;
+                    case ColumnOperation::CHANGE:
+                        $addOperation = new ColumnOperation(
+                            $columnOperation->getAfterName(),
+                            ColumnOperation::ADD,
+                            $options
+                        );
+
                         array_splice($columns, $offset, 0, [$addOperation]);
                         break;
                 }
@@ -253,12 +272,14 @@ public function apply(ReducibleOperationInterface $operation): ?ReducibleOperati
 
             foreach ($operation->getColumnOperations() as $columnOperation) {
                 $originalOperation = $columnOperation->getOperation();
+                $originalName = $columnOperation->getName();
 
-                // Remove existing operation for the column
+                // Remove existing operation for the column using proper name matching
                 foreach ($columns as $existing => $column) {
-                    if ($column->getName() === $columnOperation->getName()) {
+                    if ($column->getAfterName() === $columnOperation->getName()) {
                         unset($columns[$existing]);
                         $originalOperation = $column->getOperation();
+                        $originalName = $column->getBeforeName();
                         break;
                     }
                 }
@@ -269,14 +290,45 @@ public function apply(ReducibleOperationInterface $operation): ?ReducibleOperati
                         $columns[] = $columnOperation;
                         break;
                     case ColumnOperation::DROP:
+                        if ($originalOperation == ColumnOperation::CHANGE) {
+                            $columnOperation = new ColumnOperation(
+                                $originalName,
+                                $columnOperation->getOperation(),
+                                $columnOperation->getOptions()
+                            );
+                        }
+
                         if ($originalOperation !== ColumnOperation::ADD) {
                             $columns[] = $columnOperation;
                         }
                         break;
                     case ColumnOperation::MODIFY:
+                        $options = $columnOperation->getOptions();
+
+                        if ($originalOperation == ColumnOperation::CHANGE) {
+                            $options['new_name'] = $columnOperation->getName();
+                        }
+
                         $columns[] = new ColumnOperation(
                             $columnOperation->getName(),
                             $originalOperation,
+                            $options
+                        );
+                        break;
+                    case ColumnOperation::CHANGE:
+                        $columnName = $columnOperation->getName();
+
+                        if ($originalOperation == ColumnOperation::ADD) {
+                            $columnName = $columnOperation->getAfterName();
+                        }
+
+                        if ($originalOperation == ColumnOperation::MODIFY) {
+                            $originalOperation = ColumnOperation::CHANGE;
+                        }
+
+                        $columns[] = new ColumnOperation(
+                            $columnName,
+                            $originalOperation,
                             $columnOperation->getOptions()
                         );
                         break;

src/Operation/ViewOperation.php

@@ -27,7 +27,7 @@ final class ViewOperation extends AbstractOperation implements ReversibleOperati
      * @param string      $operation
      * @param string|null $body
      */
-    public function __construct(string $name, string $operation, string $body = null)
+    public function __construct(string $name, string $operation, ?string $body = null)
     {
         $this->name = $name;
         $this->operation = $operation;

src/ProcedureMigration.php

@@ -90,7 +90,7 @@ private function __construct(
         string $language = 'plpgsql',
         array $inParameterOperations = [],
         array $outParameterOperations = [],
-        string $body = null
+        ?string $body = null
     ) {
         $this->name = $name;
         $this->operation = $operation;

src/Statement/MysqlStatementBuilder.php

@@ -278,6 +278,16 @@ protected function buildTable(TableOperation $operation): string
                                 $this->buildColumn($columnOperation->getName(), $columnOperation->getOptions())
                             );
                             break;
+                        case ColumnOperation::CHANGE:
+                            $specifications[] = sprintf(
+                                'CHANGE COLUMN %s %s',
+                                $this->buildIdentifier($columnOperation->getName()),
+                                $this->buildColumn(
+                                    $columnOperation->getOptions()['new_name'],
+                                    $columnOperation->getOptions()
+                                )
+                            );
+                            break;
                         case ColumnOperation::DROP:
                             $specifications[] = sprintf(
                                 'DROP COLUMN %s',

src/TableMigration.php

@@ -114,6 +114,34 @@ public function modifyColumn(string $column, array $options): TableMigration
         return $this;
     }
 
+    /**
+     * Pushes a new change column operation.
+     *
+     * @param string $oldColumn
+     * @param string $newColumn
+     * @param array  $options
+     * @return TableMigration
+     */
+    public function changeColumn(string $oldColumn, string $newColumn, array $options): TableMigration
+    {
+        if ($this->operation === TableOperation::CREATE) {
+            throw new LogicException('Cannot change columns in a create migration.');
+        }
+
+        if ($this->operation === TableOperation::DROP) {
+            throw new LogicException('Cannot change columns in a drop migration.');
+        }
+
+        if ($oldColumn === $newColumn) {
+            $this->columnOperations[] = new ColumnOperation($oldColumn, ColumnOperation::MODIFY, $options);
+        } else {
+            $options['new_name'] = $newColumn;
+            $this->columnOperations[] = new ColumnOperation($oldColumn, ColumnOperation::CHANGE, $options);
+        }
+
+        return $this;
+    }
+
     /**
      * Pushes a new drop column operation.
      *

src/ViewMigration.php

@@ -61,7 +61,7 @@ public static function drop(string $name)
      * @param string      $operation
      * @param string|null $body
      */
-    private function __construct(string $name, string $operation, string $body = null)
+    private function __construct(string $name, string $operation, ?string $body = null)
     {
         $this->name = $name;
         $this->operation = $operation;

tests/Fixtures/TestChange/20211015_create_users.php

@@ -0,0 +1,4 @@
+<?php
+
+return Exo\TableMigration::create('users')
+    ->addColumn('username', ['type' => 'string']);

tests/Fixtures/TestChange/20211016_change_username_to_email.php

@@ -0,0 +1,4 @@
+<?php
+
+return Exo\TableMigration::alter('users')
+    ->changeColumn('username', 'email', ['type' => 'string']);

tests/Fixtures/TestChange/20211017_add_column_username.php

@@ -0,0 +1,4 @@
+<?php
+
+return Exo\TableMigration::alter('users')
+    ->addColumn('username', ['type' => 'string']);

tests/Fixtures/TestChange/20211018_change_username_to_user_id.php

@@ -0,0 +1,4 @@
+<?php
+
+return Exo\TableMigration::alter('users')
+    ->changeColumn('username', 'user_id', ['type' => 'integer']);