Fix #305. Empty Heredoc string causes syntax error.

Author: dim-s

exts/jphp-zend-ext/src/main/tests/strings/StringsTest.java

@@ -69,4 +69,9 @@ public void testPhpCompat() {
         check("ext/strings/001.phpt");
         check("ext/strings/002.phpt");
     }
+
+    @Test
+    public void testBug305() {
+        check("ext/strings/bug305.phpt", true);
+    }
 }

jphp-core/src/org/develnext/jphp/core/tokenizer/Tokenizer.java

@@ -277,6 +277,7 @@ protected ValueExprToken readString(StringExprToken.Quote quote, int startPositi
         List<StringExprToken.Segment> segments = new ArrayList<StringExprToken.Segment>();
 
 
+        boolean firstIter = true;
         for(; i < codeLength; i++){
             char ch = code.charAt(i);
 
@@ -288,15 +289,16 @@ protected ValueExprToken readString(StringExprToken.Quote quote, int startPositi
                 break;
             }
 
-            if (checkNewLine(ch)) {
+            if (checkNewLine(ch) || firstIter) {
                 pos = 0;
                 if (endString != null){
                     int end = i + 1 + endString.length();
-                    if (end < codeLength){
-                        if (code.substring(i + 1, end).equals(endString)) {
+                    if (end < codeLength) {
+                        String substring = firstIter ? code.substring(i, end - 1) : code.substring(i + 1, end);
+                        if (substring.equals(endString)) {
                             if ((code.charAt(end) == ';' && TokenizeGrammarUtils.isNewline(code.charAt(end + 1))) || TokenizeGrammarUtils.isNewline(code.charAt(end))) {
-                                currentPosition = i + endString.length();
-                                relativePosition = endString.length();
+                                currentPosition = firstIter ? i + endString.length() - 1 : i + endString.length();
+                                relativePosition = firstIter ?  endString.length() - 1 : endString.length();
                                 ch_quote = StringExprToken.Quote.DOC;
                                 break;
                             }
@@ -305,6 +307,8 @@ protected ValueExprToken readString(StringExprToken.Quote quote, int startPositi
                 }
             }
 
+            firstIter = false;
+
             if (!isMagic){
                 switch (ch) {
                     case '\\':

jphp-core/tests/resources/ext/strings/bug305.phpt

@@ -0,0 +1,9 @@
+--TEST--
+Empty Heredoc string causes syntax error
+--FILE--
+<?php
+$heredoc_empty_string = <<<EOD
+EOD;
+var_dump($heredoc_empty_string);
+--EXPECTF--
+string(0) ""