Fix invalid count in IterableDataReader when limit or/and offset used

CHANGELOG.md

@@ -35,6 +35,7 @@
   value meaning `return nothing` (@samdark)
 - Chg #163: Rename `FilterableDataInterface::withFilterHandlers()` to `FilterableDataInterface::withAddedFilterHandlers()` (@samdark)
 - Enh #190: Use `str_contains` for case-sensitive match in `LikeHandler` (@samdark)
+- Bug #195: Fix invalid count in `IterableDataReader` when limit or/and offset used (@vjik) 
 
 ## 1.0.1 January 25, 2023
 

src/Reader/Iterable/IterableDataReader.php

@@ -57,7 +57,7 @@ final class IterableDataReader implements DataReaderInterface
     /**
      * @psalm-var array<string, IterableFilterHandlerInterface>
      */
-    private array $iterableFilterHandlers = [];
+    private array $iterableFilterHandlers;
 
     /**
      * @param iterable $data Data to iterate.
@@ -153,27 +153,48 @@ public function getSort(): ?Sort
 
     public function count(): int
     {
-        return count($this->read());
+        return count($this->internalRead(useLimitAndOffset: false));
     }
 
     /**
      * @psalm-return array<TKey, TValue>
      */
     public function read(): array
+    {
+        return $this->internalRead(useLimitAndOffset: true);
+    }
+
+    public function readOne(): array|object|null
+    {
+        if ($this->limit === 0) {
+            return null;
+        }
+
+        /** @infection-ignore-all Any value more than one in `withLimit()` will be ignored because returned `current()` */
+        return $this
+            ->withLimit(1)
+            ->getIterator()
+            ->current();
+    }
+
+    /**
+     * @psalm-return array<TKey, TValue>
+     */
+    private function internalRead(bool $useLimitAndOffset): array
     {
         $data = [];
         $skipped = 0;
         $sortedData = $this->sort === null ? $this->data : $this->sortItems($this->data, $this->sort);
 
         foreach ($sortedData as $key => $item) {
             // Don't return more than limit items.
-            if ($this->limit > 0 && count($data) === $this->limit) {
+            if ($useLimitAndOffset && $this->limit > 0 && count($data) === $this->limit) {
                 /** @infection-ignore-all Here continue === break */
                 break;
             }
 
             // Skip offset items.
-            if ($skipped < $this->offset) {
+            if ($useLimitAndOffset && $skipped < $this->offset) {
                 ++$skipped;
                 continue;
             }
@@ -187,19 +208,6 @@ public function read(): array
         return $data;
     }
 
-    public function readOne(): array|object|null
-    {
-        if ($this->limit === 0) {
-            return null;
-        }
-
-        /** @infection-ignore-all Any value more one in `withLimit()` will be ignored because returned `current()` */
-        return $this
-            ->withLimit(1)
-            ->getIterator()
-            ->current();
-    }
-
     /**
      * Return whether an item matches iterable filter.
      *

tests/Reader/Iterable/IterableDataReaderTest.php

@@ -169,6 +169,20 @@ public function testCounting(): void
         $this->assertCount(5, $reader);
     }
 
+    public function testCountWithLimit(): void
+    {
+        $reader = (new IterableDataReader(self::DEFAULT_DATASET))->withLimit(2);
+        $this->assertSame(5, $reader->count());
+        $this->assertCount(5, $reader);
+    }
+
+    public function testCountWithOffset(): void
+    {
+        $reader = (new IterableDataReader(self::DEFAULT_DATASET))->withOffset(3);
+        $this->assertSame(5, $reader->count());
+        $this->assertCount(5, $reader);
+    }
+
     public function testReadOne(): void
     {
         $data = self::DEFAULT_DATASET;