Improving and testing the pivot method

lib/Cake/ORM/Association/BelongsToMany.php

@@ -60,6 +60,13 @@ class BelongsToMany extends Association {
  */
 	protected $_pivotTable;
 
+/**
+ * The physical name of the pivot table
+ *
+ * @var string
+ */
+	protected $_joinTable;
+
 /**
  * Sets the table instance for the pivot relation. If no arguments
  * are passed, the current configured table instance is returned
@@ -70,12 +77,15 @@ class BelongsToMany extends Association {
 	public function pivot($table = null) {
 		$target = $this->target();
 		$source = $this->source();
-		$sourceAlias = $source->alias();
-		$targetAlias = $target->alias();
+		$sAlias = $source->alias();
+		$tAlias = $target->alias();
 
 		if ($table === null) {
 			if (empty($this->_pivotTable)) {
-				$table = Table::build($sourceAlias . $targetAlias);
+				$table = Table::instance($sAlias . $tAlias);
+				$table = $table ?: Table::build($sAlias . $tAlias, [
+					'table' => $this->_joinTableName()
+				]);
 			} else {
 				return $this->_pivotTable;
 			}
@@ -85,16 +95,16 @@ public function pivot($table = null) {
 			$table = Table::build($table);
 		}
 
-		if (!$table->association($sourceAlias)) {
-			$table->belongsTo($sourceAlias)->source($this->source());
+		if (!$table->association($sAlias)) {
+			$table->belongsTo($sAlias)->source($this->source());
 		}
 
-		if (!$table->association($targetAlias)) {
-			$table->belongsTo($targetAlias)->target($this->target());
+		if (!$table->association($tAlias)) {
+			$table->belongsTo($tAlias)->target($this->target());
 		}
 
 		if (!$target->association($table->alias())) {
-			$target->belongsToMany($sourceAlias);
+			$target->belongsToMany($sAlias);
 			$target->hasMany($table->alias())->target($table);
 		}
 
@@ -197,6 +207,28 @@ protected function _buildQuery($options) {
 		return $fetchQuery;
 	}
 
+/**
+ * Sets the name of the pivot table.
+ * If no arguments are passed the current configured name is returned. A default
+ * name based of the associated tables will be generated if none found.
+ *
+ * @param string $name
+ * @return string
+ */
+	protected function _joinTableName($name = null) {
+		if ($name === null) {
+			if (empty($this->_joinTableName)) {
+				$aliases = array_map('\Cake\Utility\Inflector::tableize', [
+					$sAlias = $this->source()->alias(),
+					$tAlias = $this->target()->alias()
+				]);
+				sort($aliases);
+				$name = implode('_', $aliases);
+			}
+		}
+		return $this->_joinTable = $name;
+	}
+
 /**
  * Parse extra options passed in the constructor.
  * @param array $opts original list of options passed in constructor
@@ -207,6 +239,9 @@ protected function _options(array $opts) {
 		if (!empty($opts['through'])) {
 			$this->pivot($opts['through']);
 		}
+		if (!empty($opts['joinTable'])) {
+			$this->_joinTableName($opts['joinTable']);
+		}
 		$this->_externalOptions($opts);
 	}
 

lib/Cake/ORM/Association/ExternalAssociationTrait.php

@@ -93,6 +93,13 @@ public function requiresKeys($options = []) {
  */
 	public abstract function eagerLoader(array $options);
 
+/**
+ * Returns a single or multiple conditions to be appended to the generated join
+ * clause for getting the results on the target table.
+ *
+ * @param array $options list of options passed to attachTo method
+ * @return string|array
+ */
 	protected function _joinCondition(array $options) {
 		return sprintf('%s.%s = %s.%s',
 				$this->_sourceTable->alias(),

lib/Cake/Test/TestCase/ORM/Association/BelongsToManyTest.php

@@ -32,19 +32,17 @@ class BelongsToManyTest extends \Cake\TestSuite\TestCase {
  * @return void
  */
 	public function setUp() {
-		$this->author = Table::build('Author', [
+		$this->tag = Table::build('Tag', [
 			'schema' => [
 				'id' => ['type' => 'integer'],
-				'username' => ['type' => 'string'],
+				'name' => ['type' => 'string'],
 			]
 		]);
-		$this->article = $this->getMock(
-			'Cake\ORM\Table', ['find'], [['alias' => 'Article']]
-		);
-		$this->article->schema([
-			'id' => ['type' => 'integer'],
-			'title' => ['type' => 'string'],
-			'author_id' => ['type' => 'integer'],
+		$this->article = Table::build('Article', [
+			'schema' => [
+				'id' => ['type' => 'integer'],
+				'name' => ['type' => 'string'],
+			]
 		]);
 	}
 
@@ -93,4 +91,41 @@ public function testRequiresKeys() {
 		$this->assertFalse($assoc->requiresKeys());
 	}
 
+/**
+ * Tests the pivot method
+ *
+ * @return void
+ */
+	public function testPivot() {
+		$assoc = new BelongsToMany('Test', [
+			'sourceTable' => $this->article,
+			'targetTable' => $this->tag
+		]);
+		$pivot = $assoc->pivot();
+		$this->assertInstanceOf('\Cake\ORM\Table', $pivot);
+		$this->assertEquals('ArticleTag', $pivot->alias());
+		$this->assertEquals('articles_tags', $pivot->table());
+		$this->assertSame($this->article, $pivot->association('Article')->source());
+		$this->assertSame($this->tag, $pivot->association('Tag')->target());
+
+		$belongsTo = '\Cake\ORM\Association\BelongsTo';
+		$this->assertInstanceOf($belongsTo, $pivot->association('Article'));
+		$this->assertInstanceOf($belongsTo, $pivot->association('Tag'));
+
+		$this->assertSame($pivot, $this->tag->association('ArticleTag')->target());
+		$this->assertSame($this->article, $this->tag->association('Article')->target());
+
+		$hasMany = '\Cake\ORM\Association\HasMany';
+		$belongsToMany = '\Cake\ORM\Association\BelongsToMany';
+		$this->assertInstanceOf($belongsToMany, $this->tag->association('Article'));
+		$this->assertInstanceOf($hasMany, $this->tag->association('ArticleTag'));
+
+		$this->assertSame($pivot, $assoc->pivot());
+		$pivot2 = Table::build('Foo');
+		$assoc->pivot($pivot2);
+		$this->assertSame($pivot2, $assoc->pivot());
+
+		$assoc->pivot('ArticleTag');
+		$this->assertSame($pivot, $assoc->pivot());
+	}
 }