[4.3] Fix issue where line ending in =" is incorrectly marked as a multi-line start

Makefile

@@ -3,7 +3,7 @@ install:
 	@docker run -it -w /data -v ${PWD}:/data:delegated -v ~/.composer:/root/.composer:delegated --entrypoint composer --rm registry.gitlab.com/grahamcampbell/php:8.2-base bin all update
 
 phpunit:
-	@rm -f bootstrap/cache/*.php && docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpunit --rm registry.gitlab.com/grahamcampbell/php:8.2-cli
+	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpunit --rm registry.gitlab.com/grahamcampbell/php:8.2-cli
 
 phpstan-analyze-src:
 	@docker run -it -w /data -v ${PWD}:/data:delegated --entrypoint vendor/bin/phpstan --rm registry.gitlab.com/grahamcampbell/php:8.2-cli analyze src -c phpstan.src.neon.dist

src/Loader/Lines.php

@@ -41,15 +41,17 @@ public static function process(array $lines)
      */
     private static function multilineProcess($multiline, $line, array $buffer)
     {
+        $startsOnCurrentLine = $multiline ? false : self::looksLikeMultilineStart($line);
+
         // check if $line can be multiline variable
-        if ($started = self::looksLikeMultilineStart($line)) {
+        if ($startsOnCurrentLine) {
             $multiline = true;
         }
 
         if ($multiline) {
             array_push($buffer, $line);
 
-            if (self::looksLikeMultilineStop($line, $started)) {
+            if (self::looksLikeMultilineStop($line, $startsOnCurrentLine)) {
                 $multiline = false;
                 $line = implode("\n", $buffer);
                 $buffer = [];

tests/Dotenv/LinesTest.php

@@ -36,6 +36,7 @@ public function testProcessQuotes()
             'TEST_NS=\'test\\ntest\'',
             'TEST_EQD="https://vision.googleapis.com/v1/images:annotate?key="',
             'TEST_EQS=\'https://vision.googleapis.com/v1/images:annotate?key=\'',
+            "BASE64_ENCODED_MULTILINE=\"qS1zCzMVVUJWQShokv6YVYi+ruKSC/bHV7GmEiyVkLaBWJHNVHCHsgTksEBsy8wJ\nuwycAvR07ZyOJJed4XTRMKnKp1/v+6UATpWzkIjZXytK+pD+XlZimUHTx3uiDcmU\njhQX1wWSxHDqrSWxeIJiTD+BuUyId8FzmXQ3TcBydJ474tmOU2F492ubk3LAiZ18\nmhiRGoshXAOSbS/P3+RZi4bDeNE/No4=\"",
         ];
 
         self::assertSame($expected, Lines::process(preg_split("/(\r\n|\n|\r)/", $content)));

tests/fixtures/env/multiline.env

@@ -7,3 +7,8 @@ TEST_NS='test\ntest'
 
 TEST_EQD="https://vision.googleapis.com/v1/images:annotate?key="
 TEST_EQS='https://vision.googleapis.com/v1/images:annotate?key='
+
+BASE64_ENCODED_MULTILINE="qS1zCzMVVUJWQShokv6YVYi+ruKSC/bHV7GmEiyVkLaBWJHNVHCHsgTksEBsy8wJ
+uwycAvR07ZyOJJed4XTRMKnKp1/v+6UATpWzkIjZXytK+pD+XlZimUHTx3uiDcmU
+jhQX1wWSxHDqrSWxeIJiTD+BuUyId8FzmXQ3TcBydJ474tmOU2F492ubk3LAiZ18
+mhiRGoshXAOSbS/P3+RZi4bDeNE/No4="