CodeScanner::extractCommentsStartingWith() fixes

Author: Oscar Otero

CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 Previous releases are documented in [github releases](https://github.com/oscarotero/Gettext/releases)
 
+## [5.2.0] - Unreleased
+### Added
+- New function `CodeScanner::extractCommentsStartingWith()` to extract comments from the code.
+
 ## [5.1.0] - 2019-11-11
 ### Added
 - New function `CodeScanner::ignoreInvalidFunctions()` to ignore invalid functions instead throw an exception
@@ -37,4 +41,5 @@ Previous releases are documented in [github releases](https://github.com/oscarot
 - The library is easier to extend
 - Translation id can be independent of the context + original values, in order to be more compatible with Xliff format.
 
+[5.2.0]: https://github.com/php-gettext/Gettext/compare/v5.1.0...HEAD
 [5.1.0]: https://github.com/php-gettext/Gettext/compare/v5.0.0...v5.1.0

README.md

@@ -167,6 +167,12 @@ $phpScanner = new PhpScanner(
     Translations::create('domain3')
 );
 
+//Set a default domain, so any translations with no domain specified, will be added to that domain
+$phpScanner->setDefaultDomain('domain1');
+
+//Extract all comments starting with 'i18n:' and 'Translators:'
+$phpScanner->extractCommentsStartingWith('i18n:', 'Translators:');
+
 //Scan files
 foreach (glob('*.php') as $file) {
     $phpScanner->scanFile($file);

src/Scanner/CodeScanner.php

@@ -62,7 +62,7 @@ public function ignoreInvalidFunctions($ignore = true): self
         return $this;
     }
 
-    public function addCommentsStartingWith(string ...$prefixes): self
+    public function extractCommentsStartingWith(string ...$prefixes): self
     {
         $this->commentsPrefixes = $prefixes;
 
@@ -201,9 +201,9 @@ protected function dnpgettext(ParsedFunction $function): ?Translation
         );
     }
 
-    protected function addComments(ParsedFunction $function, Translation $translation): Translation
+    protected function addComments(ParsedFunction $function, ?Translation $translation): ?Translation
     {
-        if (empty($this->commentsPrefixes)) {
+        if (empty($this->commentsPrefixes) || empty($translation)) {
             return $translation;
         }
 
@@ -255,7 +255,7 @@ protected function checkFunction(ParsedFunction $function, int $minLength): bool
     protected function checkComment(string $comment): bool
     {
         foreach ($this->commentsPrefixes as $prefix) {
-            if (strpos($comment, $prefix) === 0) {
+            if ($prefix === '' || strpos($comment, $prefix) === 0) {
                 return true;
             }
         }