Fixed handling empty headers (#942)

* Fixed handling empty headers

* Fixed randomly failing tests

src/adapter/etl-adapter-csv/src/Flow/ETL/Adapter/CSV/CSVExtractor.php

@@ -65,6 +65,9 @@ public function extract(FlowContext $context) : \Generator
                 $headers = \array_map(fn (int $e) : string => 'e' . \str_pad((string) $e, 2, '0', STR_PAD_LEFT), \range(0, \count($rowData) - 1));
             }
 
+            $headers = \array_map(fn (string $header) : string => \trim($header), $headers);
+            $headers = \array_map(fn (string $header, int $index) : string => $header !== '' ? $header : 'e' . \str_pad((string) $index, 2, '0', STR_PAD_LEFT), $headers, \array_keys($headers));
+
             while (\is_array($rowData)) {
                 if (\count($headers) > \count($rowData)) {
                     \array_push(

src/adapter/etl-adapter-csv/tests/Flow/ETL/Adapter/CSV/Tests/Fixtures/file_with_empty_headers.csv

@@ -0,0 +1,3 @@
+,name,active
+,,false
+1,Norbert

src/adapter/etl-adapter-csv/tests/Flow/ETL/Adapter/CSV/Tests/Integration/CSVExtractorTest.php

@@ -88,6 +88,28 @@ public function test_extracting_csv_empty_columns_as_null() : void
         );
     }
 
+    public function test_extracting_csv_empty_headers() : void
+    {
+        $extractor = from_csv(
+            __DIR__ . '/../Fixtures/file_with_empty_headers.csv'
+        );
+
+        $this->assertSame(
+            [
+                [
+                    ['e00' => null, 'name' => null, 'active' => 'false'],
+                ],
+                [
+                    ['e00' => '1', 'name' => 'Norbert', 'active' => null],
+                ],
+            ],
+            \array_map(
+                fn (Rows $r) => $r->toArray(),
+                \iterator_to_array($extractor->extract(new FlowContext(Config::default())))
+            )
+        );
+    }
+
     public function test_extracting_csv_files_from_directory_recursively() : void
     {
         $extractor = from_csv(

src/core/etl/tests/Flow/ETL/Tests/Integration/DataFrame/PartitioningTest.php

@@ -142,8 +142,10 @@ public function test_pruning_multiple_partitions() : void
             ->collect()
             ->fetch();
 
+        $days = $rows->reduceToArray('day');
+        \sort($days);
         $this->assertCount(2, $rows);
-        $this->assertSame([1, 2], $rows->reduceToArray('day'));
+        $this->assertSame([1, 2], $days);
     }
 
     public function test_pruning_single_partition() : void