Implemented groupCurrentWhere() to wrap current conditions in a group so one can add condition ON TOP of existing ones

Author: Adrian Miu

composer.json

@@ -37,6 +37,9 @@
         ],
         "php-csfix": [
             "php php-cs-fixer.phar fix ./src --rules=@PSR2"
+        ],
+        "build-docs": [
+            "php docs/couscous.phar generate --target=build/docs/"
         ]
     }
 }

docs/select.md

@@ -110,6 +110,21 @@ $select->whereSprintf("publish_date <= NOW() AND parent_id = %s AND title LIKE %
 // SQL: publish_date <= NOW() and parent_id = 10 AND title LIKE '%ABC%' OR author_id = 20
 ```
 
+#### Grouping existing conditions
+
+There are times when some piece of code generates some conditions for a query and later another piece of code (via events, callbacks or decorators) attach additional conditions that work on top of the current conditions.
+
+```php
+$select->where('id', 10)
+    ->orWhere('id', 15);
+// SQL at this point: WHERE id = 10 OR id = 15
+
+// later you restrict everything
+$select->groupCurrentWhere()
+    ->where('author_id', 1);
+// SQL: WHERE (id = 10 OR id = 15) AND author_id = 15
+```
+
 ## JOINs
 
 ```php

src/Clause/Where.php

@@ -104,6 +104,13 @@ public function endSet()
         return $this;
     }
 
+    public function groupCurrentWhere()
+    {
+        $this->where->groupCurrent();
+
+        return $this;
+    }
+
     public function resetWhere()
     {
         $this->where = new Conditions($this->bindings, 'WHERE');

src/Component/Conditions.php

@@ -16,12 +16,22 @@ class Conditions extends Component
 
     protected $list = [];
 
+    protected $openedGroups = 0;
+
     public function __construct(Bindings $bindings, string $type)
     {
         $this->bindings = $bindings;
         $this->type     = $type;
     }
 
+    public function groupCurrent()
+    {
+        if (! empty($this->list)) {
+            array_unshift($this->list, '(');
+            $this->list[] = ')';
+        }
+    }
+
     public function and(string $column, $value = null, $condition = '='): void
     {
         $this->append('AND ', $this->buildExpression($column, $value, $condition));
@@ -45,11 +55,15 @@ public function orSprintf(string $format, ...$bindInline): void
     public function openGroup($type = 'AND')
     {
         $this->list[] = empty($this->list) ? '(' : $type . ' (';
+        $this->openedGroups++;
     }
 
     public function closeGroup()
     {
-        $this->list[] = ')';
+        if ($this->openedGroups > 0) {
+            $this->list[] = ')';
+            $this->openedGroups--;
+        }
     }
 
     protected function append(string $andor, string $expr): void
@@ -162,11 +176,20 @@ protected function buildExpression(string $column, $value = null, $condition = '
         return "$column $condition $bind";
     }
 
+    protected function ensureGroupsAreClosed()
+    {
+        if ($this->openedGroups > 0) {
+            $this->list[] = str_repeat(')', $this->openedGroups);
+            $this->openedGroups = 0;
+        }
+    }
+
     public function build(): string
     {
         if (empty($this->list)) {
             return '';
         }
+        $this->ensureGroupsAreClosed();
 
         return PHP_EOL . $this->type . $this->indent($this->list);
     }

tests/SelectTest.php

@@ -205,6 +205,57 @@ public function test_nested_conditions()
         ], $select->getBindValues());
     }
 
+
+    public function test_auto_closing_groups()
+    {
+        $select = $this->newSelect();
+        $select->from('posts')
+               ->columns('*')
+               ->where('id', 10)
+               ->whereStartSet()
+               ->where('parent_id', 10)
+               ->orWhere('parent_id', 11);
+
+        $expectedStatement = <<<SQL
+SELECT
+    *
+FROM
+    posts
+WHERE
+    id = :__1__
+    AND (
+        parent_id = :__2__
+        OR parent_id = :__3__
+    )
+SQL;
+
+        $this->assertSameStatement($expectedStatement, $select->getStatement());
+    }
+
+    public function test_grouping_current_conditions()
+    {
+        $select = $this->newSelect();
+        $select->from('posts')
+               ->columns('*')
+               ->where('id', 10)
+               ->orWhere('id', 11)
+               ->groupCurrentWhere()
+               ->where('title', 'abc');
+
+        $expectedStatement = <<<SQL
+SELECT
+    *
+FROM
+    posts
+WHERE
+    (id = :__1__
+    OR id = :__2__)
+    AND title = :__3__
+SQL;
+
+        $this->assertSamestatement($expectedStatement, $select->getStatement());
+    }
+
     public function test_raw_conditions()
     {
         $select = $this->newSelect();