Let expressions have columns

src/Expression.php

@@ -10,18 +10,23 @@ class Expression implements ExpressionInterface
     /** @var string The statement of the expression */
     protected $statement;
 
+    /** @var array The columns used by the expression */
+    protected $columns;
+
     /** @var array The values for the expression */
     protected $values;
 
     /**
      * Create a new database expression
      *
      * @param string $statement The statement of the expression
+     * @param array $columns The columns used by the expression
      * @param mixed  ...$values The values for the expression
      */
-    public function __construct($statement, ...$values)
+    public function __construct($statement, array $columns = null, ...$values)
     {
         $this->statement = $statement;
+        $this->columns = $columns;
         $this->values = $values;
     }
 
@@ -30,6 +35,16 @@ public function getStatement()
         return $this->statement;
     }
 
+    public function getColumns()
+    {
+        return $this->columns ?: [];
+    }
+
+    public function setColumns(array $columns)
+    {
+        $this->columns = $columns;
+    }
+
     public function getValues()
     {
         return $this->values;

src/ExpressionInterface.php

@@ -14,6 +14,22 @@ interface ExpressionInterface
      */
     public function getStatement();
 
+    /**
+     * Get the columns used by the expression
+     *
+     * @return array
+     */
+    public function getColumns();
+
+    /**
+     * Set the columns to use by the expression
+     *
+     * @param array $columns
+     *
+     * @return $this
+     */
+    public function setColumns(array $columns);
+
     /**
      * Get the values for the expression
      *

src/QueryBuilder.php

@@ -313,8 +313,7 @@ public function buildCondition(array $condition, array &$values)
                 }
             } else {
                 if ($value instanceof ExpressionInterface) {
-                    $sql[] = $value->getStatement();
-                    $values = array_merge($values, $value->getValues());
+                    $sql[] = $this->buildExpression($value, $values);
                 } elseif ($value instanceof Select) {
                     $stmt = '(' . $this->assembleSelect($value, $values)[0] . ')';
                     if (is_int($expression)) {
@@ -407,8 +406,7 @@ public function buildInsertColumnsAndValues(array $columns, array $insertValues,
 
         foreach ($insertValues as $value) {
             if ($value instanceof ExpressionInterface) {
-                $preparedValues[] = $value->getStatement();
-                $values = array_merge($values, $value->getValues());
+                $preparedValues[] = $this->buildExpression($value, $values);
             } elseif ($value instanceof Select) {
                 $preparedValues[] = "({$this->assembleSelect($value, $values)[0]})";
             } else {
@@ -451,8 +449,7 @@ public function buildSelect(array $columns, $distinct, array &$values)
 
         foreach ($columns as $alias => $column) {
             if ($column instanceof ExpressionInterface) {
-                $values = array_merge($values, $column->getValues());
-                $column = "({$column->getStatement()})";
+                $column = "({$this->buildExpression($column, $values)})";
             } elseif ($column instanceof Select) {
                 $column = "({$this->assembleSelect($column, $values)[0]})";
             }
@@ -559,8 +556,7 @@ public function buildGroupBy(array $groupBy = null, array &$values = [])
 
         foreach ($groupBy as &$column) {
             if ($column instanceof ExpressionInterface) {
-                $values = array_merge($values, $column->getValues());
-                $column = $column->getStatement();
+                $column = $this->buildExpression($column, $values);
             } elseif ($column instanceof Select) {
                 $column = "({$this->assembleSelect($column, $values)[0]})";
             }
@@ -606,8 +602,7 @@ public function buildOrderBy(array $orderBy = null, array &$values = [])
             list($column, $direction) = $column;
 
             if ($column instanceof ExpressionInterface) {
-                $values = array_merge($values, $column->getValues());
-                $column = $column->getStatement();
+                $column = $this->buildExpression($column, $values);
             } elseif ($column instanceof Select) {
                 $column = "({$this->assembleSelect($column, $values)[0]})";
             }
@@ -734,8 +729,7 @@ public function buildUpdateSet(array $set = null, array &$values = [])
 
         foreach ($set as $column => $value) {
             if ($value instanceof ExpressionInterface) {
-                $sql[] = "$column = {$value->getStatement()}";
-                $values = array_merge($values, $value->getValues());
+                $sql[] = "$column = {$this->buildExpression($value, $values)}";
             } elseif ($value instanceof Select) {
                 $sql[] = "$column = ({$this->assembleSelect($value, $values)[0]})";
             } else {
@@ -746,4 +740,25 @@ public function buildUpdateSet(array $set = null, array &$values = [])
 
         return 'SET ' . implode(', ', $sql);
     }
+
+    /**
+     * Build expression
+     *
+     * @param ExpressionInterface $expression
+     * @param array $values
+     *
+     * @return string The expression's statement
+     */
+    public function buildExpression(ExpressionInterface $expression, array &$values = [])
+    {
+        $stmt = $expression->getStatement();
+        $columns = $expression->getColumns();
+        if (! empty($columns)) {
+            $stmt = vsprintf($stmt, $columns);
+        }
+
+        $values = array_merge($values, $expression->getValues());
+
+        return $stmt;
+    }
 }

tests/HavingTest.php

@@ -57,7 +57,7 @@ public function testHavingArrayFormat()
 
     public function testWhereWithExpression()
     {
-        $expression = new Expression('c2 = ?', 1);
+        $expression = new Expression('c2 = ?', null, 1);
         $this->query->having($expression);
 
         $this->assertCorrectStatementAndValues('HAVING c2 = ?', [1]);

tests/InsertTest.php

@@ -74,7 +74,7 @@ public function testValues()
 
     public function testExpressionValue()
     {
-        $value = new Expression('x = ?', 1);
+        $value = new Expression('x = ?', null, 1);
         $this->query->values(['c1' => $value]);
 
         $this->assertSame(['c1'], $this->query->getColumns());

tests/SelectTest.php

@@ -73,7 +73,7 @@ public function testColumnsWithArrayAndAlias()
 
     public function testColumnsWithExpression()
     {
-        $columns = ['three' => new Expression('? + ?', 1, 2)];
+        $columns = ['three' => new Expression('? + ?', null, 1, 2)];
         $this->query->columns($columns);
 
         $this->assertSame($columns, $this->query->getColumns());
@@ -209,7 +209,7 @@ public function testInnerJoinWithSelect()
 
     public function testInnerJoinWithExpressionCondition()
     {
-        $condition = new Expression('t2.table1_id = ?', 1);
+        $condition = new Expression('t2.table1_id = ?', null, 1);
         $this->query->join('table2', $condition);
 
         $this->assertCorrectStatementAndValues('INNER JOIN table2 ON t2.table1_id = ?', [1]);
@@ -300,7 +300,7 @@ public function testLeftJoinWithSelect()
 
     public function testLeftJoinWithExpressionCondition()
     {
-        $condition = new Expression('t2.table1_id = ?', 1);
+        $condition = new Expression('t2.table1_id = ?', null, 1);
         $this->query->joinLeft('table2', $condition);
 
         $this->assertCorrectStatementAndValues('LEFT JOIN table2 ON t2.table1_id = ?', [1]);
@@ -391,7 +391,7 @@ public function testRightJoinWithSelect()
 
     public function testRightJoinWithExpressionCondition()
     {
-        $condition = new Expression('t2.table1_id = ?', 1);
+        $condition = new Expression('t2.table1_id = ?', null, 1);
         $this->query->joinRight('table2', $condition);
 
         $this->assertCorrectStatementAndValues('RIGHT JOIN table2 ON t2.table1_id = ?', [1]);
@@ -424,7 +424,7 @@ public function testGroupByWithAlias()
 
     public function testGroupByWithExpression()
     {
-        $column = new Expression('x = ?', 1);
+        $column = new Expression('x = ?', null, 1);
         $this->query->groupBy([$column]);
 
         $this->assertCorrectStatementAndValues('GROUP BY x = ?', [1]);
@@ -447,15 +447,15 @@ public function testOrderBy()
 
     public function testOrderByWithExpression()
     {
-        $column = new Expression('x = ?', 1);
+        $column = new Expression('x = ?', null, 1);
         $this->query->orderBy($column, 'DESC');
 
         $this->assertCorrectStatementAndValues('ORDER BY x = ? DESC', [1]);
     }
 
     public function testOrderByWithExpressionAndExplicitDirection()
     {
-        $column = new Expression('x = ?', 1);
+        $column = new Expression('x = ?', null, 1);
         $this->query->orderBy([[$column, 'DESC']]);
 
         $this->assertCorrectStatementAndValues('ORDER BY x = ? DESC', [1]);

tests/UpdateTest.php

@@ -62,7 +62,7 @@ public function testSet()
 
     public function testExpressionValue()
     {
-        $value = new Expression('x = ?', 1);
+        $value = new Expression('x = ?', null, 1);
         $this->query->set(['c1' => $value]);
 
         $this->assertSame(['c1' => $value], $this->query->getSet());

tests/WhereTest.php

@@ -204,7 +204,7 @@ public function testPartiallyPreparedWhere()
 
     public function testWhereWithExpression()
     {
-        $expression = new Expression('c2 = ?', 1);
+        $expression = new Expression('c2 = ?', null, 1);
         $this->query->where($expression);
 
         $this->assertCorrectStatementAndValues('WHERE c2 = ?', [1]);