Split ResultSetInterface into capability interfaces

src/ResultSet/AbstractResultSet.php

@@ -17,10 +17,7 @@
 
 use function count;
 use function current;
-use function gettype;
 use function is_array;
-use function is_object;
-use function method_exists;
 use function reset;
 
 abstract class AbstractResultSet implements ResultSetInterface
@@ -43,70 +40,63 @@ abstract class AbstractResultSet implements ResultSetInterface
     protected int $position = 0;
 
     /**
-     * Set the data source for the result set
-     *
-     * @throws InvalidArgumentException|Exception
+     * @throws RuntimeException
      */
-    #[Override]
-    public function initialize(iterable $dataSource): ResultSetInterface
+    public function buffer(): ResultSetInterface
     {
-        // reset buffering
-        if (is_array($this->buffer)) {
+        if ($this->buffer === -2) {
+            throw new RuntimeException('Buffering must be enabled before iteration is started');
+        } elseif ($this->buffer === null) {
             $this->buffer = [];
-        }
-
-        if ($dataSource instanceof ResultInterface) {
-            $this->fieldCount = $dataSource->getFieldCount();
-            $this->dataSource = $dataSource;
-            if ($dataSource->isBuffered()) {
-                $this->buffer = -1;
-            }
-
-            if (is_array($this->buffer)) {
+            if ($this->dataSource instanceof ResultInterface) {
                 $this->dataSource->rewind();
             }
-
-            return $this;
-        }
-
-        if (is_array($dataSource)) {
-            // its safe to get numbers from an array
-            $first = current($dataSource);
-            reset($dataSource);
-            $this->fieldCount = $first === false ? 0 : count($first);
-            $this->dataSource = new ArrayIterator($dataSource);
-            $this->buffer     = -1; // array's are a natural buffer
-        } elseif ($dataSource instanceof IteratorAggregate) {
-            /** @phpstan-ignore assign.propertyType */
-            $this->dataSource = $dataSource->getIterator();
-        } else {
-            /** @phpstan-ignore assign.propertyType */
-            $this->dataSource = $dataSource;
         }
 
         return $this;
     }
 
     /**
-     * @throws RuntimeException
+     * Countable: return count of rows
      */
-    public function buffer(): ResultSetInterface
+    #[Override]
+    #[ReturnTypeWillChange]
+    public function count(): ?int
     {
-        if ($this->buffer === -2) {
-            throw new RuntimeException('Buffering must be enabled before iteration is started');
-        } elseif ($this->buffer === null) {
-            $this->buffer = [];
-            if ($this->dataSource instanceof ResultInterface) {
-                $this->dataSource->rewind();
-            }
+        if ($this->count !== null) {
+            return $this->count;
         }
 
-        return $this;
+        if ($this->dataSource instanceof Countable) {
+            $this->count = count($this->dataSource);
+        }
+
+        return $this->count;
     }
 
-    public function isBuffered(): bool
+    /**
+     * Iterator: get current item
+     */
+    #[Override]
+    public function current(): array|object|null
     {
-        return $this->buffer === -1 || is_array($this->buffer);
+        if (-1 === $this->buffer) {
+            // datasource was an array when the resultset was initialized
+            return $this->dataSource->current();
+        }
+
+        if ($this->buffer === null) {
+            $this->buffer = -2; // implicitly disable buffering from here on
+        } elseif (is_array($this->buffer) && isset($this->buffer[$this->position])) {
+            return $this->buffer[$this->position];
+        }
+
+        $data = $this->dataSource->current();
+        if (is_array($this->buffer)) {
+            $this->buffer[$this->position] = $data;
+        }
+
+        return is_array($data) ? $data : null;
     }
 
     /**
@@ -150,20 +140,53 @@ public function getFieldCount(): int
     }
 
     /**
-     * Iterator: move pointer to next item
+     * Set the data source for the result set
+     *
+     * @throws InvalidArgumentException|Exception
      */
     #[Override]
-    public function next(): void
+    public function initialize(iterable $dataSource): ResultSetInterface
     {
-        if ($this->buffer === null) {
-            $this->buffer = -2; // implicitly disable buffering from here on
+        // reset buffering
+        if (is_array($this->buffer)) {
+            $this->buffer = [];
         }
 
-        if (! is_array($this->buffer) || $this->position === $this->dataSource->key()) {
-            $this->dataSource->next();
+        if ($dataSource instanceof ResultInterface) {
+            $this->fieldCount = $dataSource->getFieldCount();
+            $this->dataSource = $dataSource;
+            if ($dataSource->isBuffered()) {
+                $this->buffer = -1;
+            }
+
+            if (is_array($this->buffer)) {
+                $this->dataSource->rewind();
+            }
+
+            return $this;
         }
 
-        $this->position++;
+        if (is_array($dataSource)) {
+            // its safe to get numbers from an array
+            $first = current($dataSource);
+            reset($dataSource);
+            $this->fieldCount = $first === false ? 0 : count($first);
+            $this->dataSource = new ArrayIterator($dataSource);
+            $this->buffer     = -1; // array's are a natural buffer
+        } elseif ($dataSource instanceof IteratorAggregate) {
+            /** @phpstan-ignore assign.propertyType */
+            $this->dataSource = $dataSource->getIterator();
+        } else {
+            /** @phpstan-ignore assign.propertyType */
+            $this->dataSource = $dataSource;
+        }
+
+        return $this;
+    }
+
+    public function isBuffered(): bool
+    {
+        return $this->buffer === -1 || is_array($this->buffer);
     }
 
     /**
@@ -176,41 +199,20 @@ public function key(): int
     }
 
     /**
-     * Iterator: get current item
+     * Iterator: move pointer to next item
      */
     #[Override]
-    public function current(): array|object|null
+    public function next(): void
     {
-        if (-1 === $this->buffer) {
-            // datasource was an array when the resultset was initialized
-            return $this->dataSource->current();
-        }
-
         if ($this->buffer === null) {
             $this->buffer = -2; // implicitly disable buffering from here on
-        } elseif (is_array($this->buffer) && isset($this->buffer[$this->position])) {
-            return $this->buffer[$this->position];
         }
 
-        $data = $this->dataSource->current();
-        if (is_array($this->buffer)) {
-            $this->buffer[$this->position] = $data;
-        }
-
-        return is_array($data) ? $data : null;
-    }
-
-    /**
-     * Iterator: is pointer valid?
-     */
-    #[Override]
-    public function valid(): bool
-    {
-        if (is_array($this->buffer) && isset($this->buffer[$this->position])) {
-            return true;
+        if (! is_array($this->buffer) || $this->position === $this->dataSource->key()) {
+            $this->dataSource->next();
         }
 
-        return $this->dataSource->valid();
+        $this->position++;
     }
 
     /**
@@ -227,53 +229,15 @@ public function rewind(): void
     }
 
     /**
-     * Countable: return count of rows
-     */
-    #[Override]
-    #[ReturnTypeWillChange]
-    public function count(): ?int
-    {
-        if ($this->count !== null) {
-            return $this->count;
-        }
-
-        if ($this->dataSource instanceof Countable) {
-            $this->count = count($this->dataSource);
-        }
-
-        return $this->count;
-    }
-
-    /**
-     * Cast result set to array of arrays
-     *
-     * @throws RuntimeException If any row is not castable to an array.
+     * Iterator: is pointer valid?
      */
     #[Override]
-    public function toArray(): array
+    public function valid(): bool
     {
-        $return = [];
-        foreach ($this as $row) {
-            if (is_array($row)) {
-                $return[] = $row;
-                continue;
-            }
-
-            if (
-                ! is_object($row)
-                || (
-                    ! method_exists($row, 'toArray')
-                    && ! method_exists($row, 'getArrayCopy')
-                )
-            ) {
-                throw new RuntimeException(
-                    'Rows as part of this DataSource, with type ' . gettype($row) . ' cannot be cast to an array'
-                );
-            }
-
-            $return[] = method_exists($row, 'toArray') ? $row->toArray() : $row->getArrayCopy();
+        if (is_array($this->buffer) && isset($this->buffer[$this->position])) {
+            return true;
         }
 
-        return $return;
+        return $this->dataSource->valid();
     }
 }

src/ResultSet/ArrayObjectResultSetInterface.php

@@ -0,0 +1,17 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpDb\ResultSet;
+
+use ArrayObject;
+
+/**
+ * Capability interface for a ResultSet whose rows clone an ArrayObject prototype.
+ */
+interface ArrayObjectResultSetInterface
+{
+    public function getRowPrototype(): ArrayObject;
+
+    public function setRowPrototype(ArrayObject $rowPrototype): ResultSetInterface&ArrayObjectResultSetInterface;
+}

src/ResultSet/Exception/ExceptionInterface.php

@@ -6,6 +6,4 @@
 
 use PhpDb\Exception;
 
-interface ExceptionInterface extends Exception\ExceptionInterface
-{
-}
+interface ExceptionInterface extends Exception\ExceptionInterface {}

src/ResultSet/Exception/InvalidArgumentException.php

@@ -6,6 +6,4 @@
 
 use PhpDb\Exception;
 
-class InvalidArgumentException extends Exception\InvalidArgumentException implements ExceptionInterface
-{
-}
+class InvalidArgumentException extends Exception\InvalidArgumentException implements ExceptionInterface {}

src/ResultSet/Exception/RuntimeException.php

@@ -6,6 +6,4 @@
 
 use PhpDb\Exception;
 
-class RuntimeException extends Exception\RuntimeException implements ExceptionInterface
-{
-}
+class RuntimeException extends Exception\RuntimeException implements ExceptionInterface {}