Added tests to fetch empty strings with wrong php types (#1169)

source/shared/core_stmt.cpp

@@ -1844,6 +1844,7 @@ void core_get_field_common( _Inout_ sqlsrv_stmt* stmt, _In_ SQLUSMALLINT field_i
         {
             sqlsrv_malloc_auto_ptr<double> field_value_temp;
             field_value_temp = static_cast<double*>( sqlsrv_malloc( sizeof( double )));
+            *field_value_temp = 0.0;
 
             SQLRETURN r = stmt->current_results->get_data( field_index + 1, SQL_C_DOUBLE, field_value_temp, sizeof( double ),
                                                            field_len, true /*handle_warning*/ );

test/functional/sqlsrv/srv_013_sqlsrv_get_field.phpt

@@ -1,6 +1,7 @@
 --TEST--
-sqlsrv_get_field() using SQLSRV_PHPTYPE_STREAM(SQLSRV_ENC_CHAR)
+Test sqlsrv_get_field() using SQLSRV_PHPTYPE_STREAM(SQLSRV_ENC_CHAR)
 --SKIPIF--
+<?php require('skipif.inc'); ?>
 --FILE--
 <?php
 

test/functional/sqlsrv/srv_014_sqlsrv_get_field.phpt

@@ -1,6 +1,7 @@
 --TEST--
-sqlsrv_get_field() using SQLSRV_PHPTYPE_STREAM(SQLSRV_ENC_BINARY)
+Test sqlsrv_get_field() using SQLSRV_PHPTYPE_STREAM(SQLSRV_ENC_BINARY)
 --SKIPIF--
+<?php require('skipif.inc'); ?>
 --FILE--
 <?php
 

test/functional/sqlsrv/srv_015_sqlsrv_get_field_nulls.phpt

@@ -0,0 +1,87 @@
+--TEST--
+Test sqlsrv_get_field() with empty and null varchar fields using incorrect PHP types 
+--SKIPIF--
+<?php require('skipif.inc'); ?>
+--FILE--
+<?php
+
+require_once("MsCommon.inc");
+
+$tableName = 'sqlsrv_get_field_nulls';
+
+// connect
+$conn = connect();
+if (!$conn) {
+    fatalError("Connection could not be established.\n");
+}
+
+// Create table
+dropTable($conn, $tableName);
+
+$query = "CREATE TABLE $tableName (ID VARCHAR(10) NULL)";
+$stmt = sqlsrv_query($conn, $query);
+
+// Insert empty string and NULL value
+$query = "INSERT INTO $tableName VALUES (''), (NULL)";
+$stmt = sqlsrv_query($conn, $query);
+if (!$stmt) {
+    fatalError("Failed to insert rows");
+}
+
+// Fetch data
+$query = "SELECT * FROM $tableName";
+$stmt = sqlsrv_prepare($conn, $query);
+if (!$stmt) {
+    fatalError("Failed to prepare query");
+}
+
+sqlsrv_execute($stmt);
+
+while (sqlsrv_fetch($stmt)) {
+    $field = sqlsrv_get_field($stmt, 0, SQLSRV_PHPTYPE_FLOAT);
+    var_dump($field);
+}
+
+sqlsrv_execute($stmt);
+
+while (sqlsrv_fetch($stmt)) {
+    $field = sqlsrv_get_field($stmt, 0, SQLSRV_PHPTYPE_INT);
+    var_dump($field);
+}
+
+sqlsrv_execute($stmt);
+
+// When fetched as datetime, an empty string means indicates the current time
+while (sqlsrv_fetch($stmt)) {
+    $field = sqlsrv_get_field($stmt, 0, SQLSRV_PHPTYPE_DATETIME);
+    
+    if (is_null($field)) {
+        var_dump($field);
+    } else {
+        $date = date_create('');
+        $str1 = date_format($date, "Y/m/d");
+        $str2 = date_format($field, "Y/m/d");
+        
+        // It suffices to compare just the date
+        if (strcmp($str1, $str2)) {
+            echo "Fetched value is unexpected:\n";
+            var_dump($field);
+        }
+    }
+}
+
+dropTable($conn, $tableName);
+
+// Close connection
+sqlsrv_free_stmt($stmt);
+sqlsrv_close($conn);
+print "Done"
+?>
+
+--EXPECT--
+float(0)
+NULL
+int(0)
+NULL
+NULL
+Done