Fix result set rows for DDL queries to be null, instead of empty array

The result set for DDL queries (INSERT, UPDATE, DELETE etc.) is empty,
i.e. it does not contain any columns or rows. Columns and rows should
thus be represented by a null value. In contrast, an empty result set
from a SELECT query will always contain a non-empty array of columns and
may contain any number of rows (possibly an empty array of rows).

Author: clue

res/sqlite-worker.php

@@ -172,16 +172,15 @@
                 'error' => array('message' => $db->lastErrorMsg())
             ));
         } else {
-            $columns = array();
-            for ($i = 0, $n = $result->numColumns(); $i < $n; ++$i) {
-                $columns[] = $result->columnName($i);
-            }
-
-            $rows = array();
             if ($result->numColumns() !== 0) {
                 // Fetch all rows only if this result set has any columns.
                 // INSERT/UPDATE/DELETE etc. do not return any columns, trying
                 // to fetch the results here will issue the same query again.
+                $rows = $columns = [];
+                for ($i = 0, $n = $result->numColumns(); $i < $n; ++$i) {
+                    $columns[] = $result->columnName($i);
+                }
+
                 while (($row = $result->fetchArray(\SQLITE3_ASSOC)) !== false) {
                     // base64-encode any string that is not valid UTF-8 without control characters (BLOB)
                     foreach ($row as &$value) {
@@ -193,6 +192,8 @@
                     }
                     $rows[] = $row;
                 }
+            } else {
+                $rows = $columns = null;
             }
             $result->finalize();
 

src/Io/ProcessIoDatabase.php

@@ -90,18 +90,19 @@ public function query($sql, array $params = array())
             $result->changed = $data['changed'];
             $result->insertId = $data['insertId'];
             $result->columns = $data['columns'];
+            $result->rows = $data['rows'];
 
             // base64-decode string result values for BLOBS
-            $result->rows = [];
-            foreach ($data['rows'] as $row) {
-                foreach ($row as &$value) {
-                    if (isset($value['base64'])) {
-                        $value = \base64_decode($value['base64']);
-                    } elseif (isset($value['float'])) {
-                        $value = (float)$value['float'];
+            if ($result->rows !== null) {
+                foreach ($result->rows as &$row) {
+                    foreach ($row as &$value) {
+                        if (isset($value['base64'])) {
+                            $value = \base64_decode($value['base64']);
+                        } elseif (isset($value['float'])) {
+                            $value = (float)$value['float'];
+                        }
                     }
                 }
-                $result->rows[] = $row;
             }
 
             return $result;

tests/FunctionalDatabaseTest.php

@@ -658,7 +658,7 @@ public function testExecRejectsWhenAlreadyClosed($flag)
      * @dataProvider provideSocketFlags
      * @param bool $flag
      */
-    public function testQueryInsertResolvesWithResultWithLastInsertIdAndRunsUntilQuit($flag)
+    public function testQueryInsertResolvesWithEmptyResultSetWithLastInsertIdAndRunsUntilQuit($flag)
     {
         $loop = React\EventLoop\Factory::create();
         $factory = new Factory($loop);
@@ -673,15 +673,50 @@ public function testQueryInsertResolvesWithResultWithLastInsertIdAndRunsUntilQui
         $promise->then(function (DatabaseInterface $db) use (&$data){
             $db->exec('CREATE TABLE foo (id INTEGER PRIMARY KEY AUTOINCREMENT, bar STRING)');
             $db->query('INSERT INTO foo (bar) VALUES (?)', ['test'])->then(function (Result $result) use (&$data) {
-                $data = $result->insertId;
-            });
+                $data = $result;
+            }, 'printf');
+
+            $db->quit();
+        });
+
+        $loop->run();
+
+        $this->assertInstanceOf('Clue\React\SQLite\Result', $data);
+        $this->assertSame(1, $data->insertId);
+        $this->assertNull($data->columns);
+        $this->assertNull($data->rows);
+    }
+
+    /**
+     * @dataProvider provideSocketFlags
+     * @param bool $flag
+     */
+    public function testQuerySelectEmptyResolvesWithEmptyResultSetWithColumnsAndNoRowsAndRunsUntilQuit($flag)
+    {
+        $loop = React\EventLoop\Factory::create();
+        $factory = new Factory($loop);
+
+        $ref = new ReflectionProperty($factory, 'useSocket');
+        $ref->setAccessible(true);
+        $ref->setValue($factory, $flag);
+
+        $promise = $factory->open(':memory:');
+
+        $data = null;
+        $promise->then(function (DatabaseInterface $db) use (&$data){
+            $db->exec('CREATE TABLE foo (id INTEGER PRIMARY KEY AUTOINCREMENT, bar STRING)');
+            $db->query('SELECT * FROM foo LIMIT 0')->then(function (Result $result) use (&$data) {
+                $data = $result;
+            }, 'printf');
 
             $db->quit();
         });
 
         $loop->run();
 
-        $this->assertSame(1, $data);
+        $this->assertInstanceOf('Clue\React\SQLite\Result', $data);
+        $this->assertSame(['id', 'bar'], $data->columns);
+        $this->assertSame([], $data->rows);
     }
 
     protected function expectCallableNever()