[12.x] Add foreign id to morph conversion methods to Blueprint

src/Illuminate/Database/Schema/Blueprint.php

@@ -1048,6 +1048,80 @@ public function foreignIdFor($model, $column = null)
             ->referencesModelColumn($model->getKeyName());
     }
 
+    /**
+     * Convert a foreign key column to a polymorphic relationship (integer IDs).
+     *
+     * @param  string  $column
+     * @param  string  $morphName
+     * @param  string  $defaultOwnerType
+     * @return void
+     */
+    public function foreignIdToMorph($column, $morphName, $defaultOwnerType)
+    {
+        $this->convertToMorph($column, $morphName, $defaultOwnerType, 'bigInteger', ['unsigned' => true]);
+    }
+
+    /**
+     * Convert a foreign key column to a polymorphic relationship (UUID IDs).
+     *
+     * @param  string  $column
+     * @param  string  $morphName
+     * @param  string  $defaultOwnerType
+     * @return void
+     */
+    public function foreignIdToUuidMorph($column, $morphName, $defaultOwnerType)
+    {
+        $this->convertToMorph($column, $morphName, $defaultOwnerType, 'uuid');
+    }
+
+    /**
+     * Convert a foreign key column to a polymorphic relationship (ULID IDs).
+     *
+     * @param  string  $column
+     * @param  string  $morphName
+     * @param  string  $defaultOwnerType
+     * @return void
+     */
+    public function foreignIdToUlidMorph($column, $morphName, $defaultOwnerType)
+    {
+        $this->convertToMorph($column, $morphName, $defaultOwnerType, 'char', ['length' => 26]);
+    }
+
+    /**
+     * Convert a foreign key column to a polymorphic relationship.
+     *
+     * @param  string  $column
+     * @param  string  $morphName
+     * @param  string  $defaultOwnerType
+     * @param  string  $columnType
+     * @param  array  $columnOptions
+     * @return void
+     */
+    protected function convertToMorph($column, $morphName, $defaultOwnerType, $columnType, $columnOptions = [])
+    {
+        // Drop the foreign key constraint if it exists
+        $this->dropForeign([$column]);
+
+        // Rename the column first
+        $this->renameColumn($column, "{$morphName}_id");
+
+        // Change the column type
+        $this->addColumn($columnType, "{$morphName}_id", $columnOptions)->change();
+
+        // Add the morph type column
+        $this->string("{$morphName}_type")->after("{$morphName}_id")->nullable();
+
+        // Add index for the morph columns
+        $this->index(["{$morphName}_type", "{$morphName}_id"]);
+
+        // Add command to update existing records with the default owner type
+        $this->addCommand('updateMorphType', [
+            'morphIdColumn' => "{$morphName}_id",
+            'morphTypeColumn' => "{$morphName}_type",
+            'defaultOwnerType' => $defaultOwnerType,
+        ]);
+    }
+
     /**
      * Create a new float column on the table.
      *

src/Illuminate/Database/Schema/Grammars/Grammar.php

@@ -507,4 +507,23 @@ public function supportsSchemaTransactions()
     {
         return $this->transactions;
     }
+
+    /**
+     * Compile an update morph type command.
+     *
+     * @param  \Illuminate\Database\Schema\Blueprint  $blueprint
+     * @param  \Illuminate\Support\Fluent  $command
+     * @return string
+     */
+    public function compileUpdateMorphType(Blueprint $blueprint, Fluent $command)
+    {
+        return sprintf(
+            'update %s set %s = %s where %s is not null and %s is null',
+            $this->wrapTable($blueprint->getTable()),
+            $this->wrap($command->morphTypeColumn),
+            $this->getDefaultValue($command->defaultOwnerType),
+            $this->wrap($command->morphIdColumn),
+            $this->wrap($command->morphTypeColumn)
+        );
+    }
 }

src/Illuminate/Database/Schema/Grammars/MySqlGrammar.php

@@ -1390,4 +1390,23 @@ protected function wrapJsonSelector($value)
 
         return 'json_unquote(json_extract('.$field.$path.'))';
     }
+
+    /**
+     * Compile an update morph type command.
+     *
+     * @param  \Illuminate\Database\Schema\Blueprint  $blueprint
+     * @param  \Illuminate\Support\Fluent  $command
+     * @return string
+     */
+    public function compileUpdateMorphType(Blueprint $blueprint, Fluent $command)
+    {
+        return sprintf(
+            'update %s set %s = %s where %s is not null and %s is null',
+            $this->wrapTable($blueprint->getTable()),
+            $this->wrap($command->morphTypeColumn),
+            $this->getDefaultValue(addslashes($command->defaultOwnerType)),
+            $this->wrap($command->morphIdColumn),
+            $this->wrap($command->morphTypeColumn)
+        );
+    }
 }

tests/Database/DatabaseSchemaBlueprintTest.php

@@ -413,6 +413,90 @@ public function testDefaultUsingNullableUlidMorph()
         ], $getSql('MySql'));
     }
 
+    public function testForeignIdToMorph()
+    {
+        $getSql = function ($grammar) {
+            if ($grammar == 'MySql') {
+                $connection = $this->getConnection($grammar);
+                $connection->shouldReceive('getServerVersion')->andReturn('8.0.4');
+                $connection->shouldReceive('isMaria')->andReturn(false);
+
+                return (new Blueprint($connection, 'posts', function ($table) {
+                    $table->foreignIdToMorph('user_id', 'author', 'App\Models\Post');
+                }))->toSql();
+            } else {
+                return $this->getBlueprint($grammar, 'posts', function ($table) {
+                    $table->foreignIdToMorph('user_id', 'author', 'App\Models\Post');
+                })->toSql();
+            }
+        };
+
+        $this->assertEquals([
+            'alter table `posts` drop foreign key `posts_user_id_foreign`',
+            'alter table `posts` rename column `user_id` to `author_id`',
+            'alter table `posts` modify `author_id` bigint unsigned not null',
+            'alter table `posts` add `author_type` varchar(255) null after `author_id`',
+            'alter table `posts` add index `posts_author_type_author_id_index`(`author_type`, `author_id`)',
+            'update `posts` set `author_type` = \'App\\\\Models\\\\Post\' where `author_id` is not null and `author_type` is null',
+        ], $getSql('MySql'));
+    }
+
+    public function testForeignIdToUuidMorph()
+    {
+        $getSql = function ($grammar) {
+            if ($grammar == 'MySql') {
+                $connection = $this->getConnection($grammar);
+                $connection->shouldReceive('getServerVersion')->andReturn('8.0.4');
+                $connection->shouldReceive('isMaria')->andReturn(false);
+
+                return (new Blueprint($connection, 'posts', function ($table) {
+                    $table->foreignIdToUuidMorph('user_id', 'author', 'App\Models\Post');
+                }))->toSql();
+            } else {
+                return $this->getBlueprint($grammar, 'posts', function ($table) {
+                    $table->foreignIdToUuidMorph('user_id', 'author', 'App\Models\Post');
+                })->toSql();
+            }
+        };
+
+        $this->assertEquals([
+            'alter table `posts` drop foreign key `posts_user_id_foreign`',
+            'alter table `posts` rename column `user_id` to `author_id`',
+            'alter table `posts` modify `author_id` char(36) not null',
+            'alter table `posts` add `author_type` varchar(255) null after `author_id`',
+            'alter table `posts` add index `posts_author_type_author_id_index`(`author_type`, `author_id`)',
+            'update `posts` set `author_type` = \'App\\\\Models\\\\Post\' where `author_id` is not null and `author_type` is null',
+        ], $getSql('MySql'));
+    }
+
+    public function testForeignIdToUlidMorph()
+    {
+        $getSql = function ($grammar) {
+            if ($grammar == 'MySql') {
+                $connection = $this->getConnection($grammar);
+                $connection->shouldReceive('getServerVersion')->andReturn('8.0.4');
+                $connection->shouldReceive('isMaria')->andReturn(false);
+
+                return (new Blueprint($connection, 'posts', function ($table) {
+                    $table->foreignIdToUlidMorph('user_id', 'author', 'App\Models\Post');
+                }))->toSql();
+            } else {
+                return $this->getBlueprint($grammar, 'posts', function ($table) {
+                    $table->foreignIdToUlidMorph('user_id', 'author', 'App\Models\Post');
+                })->toSql();
+            }
+        };
+
+        $this->assertEquals([
+            'alter table `posts` drop foreign key `posts_user_id_foreign`',
+            'alter table `posts` rename column `user_id` to `author_id`',
+            'alter table `posts` modify `author_id` char(26) not null',
+            'alter table `posts` add `author_type` varchar(255) null after `author_id`',
+            'alter table `posts` add index `posts_author_type_author_id_index`(`author_type`, `author_id`)',
+            'update `posts` set `author_type` = \'App\\\\Models\\\\Post\' where `author_id` is not null and `author_type` is null',
+        ], $getSql('MySql'));
+    }
+
     public function testGenerateRelationshipColumnWithIncrementalModel()
     {
         $getSql = function ($grammar) {