Corrected behavior on parse an empty file

Author: sergeyklay

CHANGELOG.md

@@ -6,7 +6,11 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [Unreleased]
 ### Fixed
-- Fixed syntax error with final class and use of extends and implements [#48](https://github.com/phalcon/php-zephir-parser/issues/48)
+- Fixed syntax error with final class and use of extends and implements
+  [#48](https://github.com/phalcon/php-zephir-parser/issues/48)
+- Corrected behavior on parse an empty file. Now an empty
+  [IR](https://en.wikipedia.org/wiki/Intermediate_representation)
+  (as an array) will be returned
 
 ### Removed
 - PHP 5.x no longer supported. PHP 5.x users should use previous releases
@@ -17,10 +21,12 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ## [1.1.3] - 2018-11-06
 ### Changed
-- Extremely simplified installation of the extension using standard PHP workflow [#38](https://github.com/phalcon/php-zephir-parser/issues/38)
+- Extremely simplified installation of the extension using standard PHP workflow
+  [#38](https://github.com/phalcon/php-zephir-parser/issues/38)
 
 ### Fixed
-- Improved error handling and prevent segfault on invalid syntax [#30](https://github.com/phalcon/php-zephir-parser/issues/30)
+- Improved error handling and prevent segfault on invalid syntax
+  [#30](https://github.com/phalcon/php-zephir-parser/issues/30)
 
 ### Removed
 - Removed no longer needed BASH scripts to build and install extension
@@ -30,7 +36,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - Added ability to build Windows DLLs for PHP 7.2
 
 ### Changed
-- Removed ability to build Windows DLLs for PHP 5.x. Windows users with PHP 5.x should use Zephir Parser <= 1.1.1 (see latest releases).
+- Removed ability to build Windows DLLs for PHP 5.x.
+  Windows users with PHP 5.x should use Zephir Parser <= 1.1.1 (see latest releases).
 
 ## [1.1.1] - 2017-11-09
 ### Changed
@@ -40,14 +47,17 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Fixed
 - Fixed `mod-assign` operator recognition
-- Fixed issue with incorrectly used `YYMARKER` and `YYCURSOR` [#31](https://github.com/phalcon/php-zephir-parser/issues/31),
-[phalcon/zephir#1591](https://github.com/phalcon/zephir/issues/1591), [phalcon/cphalcon#13140](https://github.com/phalcon/cphalcon/issues/13140)
+- Fixed issue with incorrectly used `YYMARKER` and `YYCURSOR`
+  [#31](https://github.com/phalcon/php-zephir-parser/issues/31),
+  [phalcon/zephir#1591](https://github.com/phalcon/zephir/issues/1591),
+  [phalcon/cphalcon#13140](https://github.com/phalcon/cphalcon/issues/13140)
 - Improved scanner by removing redundant rules
 
 ## [1.1.0] - 2017-10-12
 ### Added
-- Added support syntax assign-bitwise operators [#14](https://github.com/phalcon/php-zephir-parser/issues/14),
-[phalcon/zephir#1056](https://github.com/phalcon/zephir/issues/1056)
+- Added support syntax assign-bitwise operators
+  [#14](https://github.com/phalcon/php-zephir-parser/issues/14),
+  [phalcon/zephir#1056](https://github.com/phalcon/zephir/issues/1056)
 
 ### Changed
 - Refactor tests to use more standard approach usually used for PHP extensions

parser/base.c

@@ -68,7 +68,8 @@ void xx_parse_program(zval *return_value, char *program, size_t program_length,
 	/**
 	 * Check if the program has any length
 	 */
-	if (program_length < 2) {
+	if (program_length < 2 || is_empty(program)) {
+		array_init(return_value);
 		return;
 	}
 

parser/parser.c

@@ -8611,7 +8611,8 @@ void xx_parse_program(zval *return_value, char *program, size_t program_length,
 	/**
 	 * Check if the program has any length
 	 */
-	if (program_length < 2) {
+	if (program_length < 2 || is_empty(program)) {
+		array_init(return_value);
 		return;
 	}
 

parser/parser.h

@@ -1,10 +1,25 @@
 #include <php.h>
 #include <string.h>
+#include <ctype.h>
 
 #include "zephir.h"
 #include "xx.h"
 #include "scanner.h"
 
+/**
+ * Check if all characters are whitespace.
+ */
+static int is_empty(const char *program)
+{
+	while (*program != '\0') {
+		if (!isspace((unsigned char)*program))
+			return 0;
+		program++;
+	}
+
+	return 1;
+}
+
 static void parser_add_str(zval *arr, const char *key, const char *val) {
 	zval tmp;
 	zend_string *tmp_str = zend_string_init(val, strlen(val), 0);

tests/base/empty01.phpt

@@ -0,0 +1,9 @@
+--TEST--
+test me
+--SKIPIF--
+<?php include(__DIR__ . '/../skipif.inc'); ?>
+--FILE--
+<?php var_dump(zephir_parse_file(' ', '(eval code)')); ?>
+--EXPECT--
+array(0) {
+}

tests/base/empty02.phpt

@@ -0,0 +1,9 @@
+--TEST--
+test me
+--SKIPIF--
+<?php include(__DIR__ . '/../skipif.inc'); ?>
+--FILE--
+<?php var_dump(zephir_parse_file("\n\n\t                  \n\n\t \r\n\t", '(eval code)')); ?>
+--EXPECT--
+array(0) {
+}