Adding inspection engine

Author: nyamsprod

phpstan-build.neon

@@ -19,4 +19,6 @@ parameters:
     treatPhpDocTypesAsCertain: false
     parallel:
         processTimeout: 300.0
+    bootstrapFiles:
+        - vendor/autoload.php
 

phpstan.neon

@@ -22,4 +22,6 @@ parameters:
     treatPhpDocTypesAsCertain: false
     parallel:
         processTimeout: 300.0
+    bootstrapFiles:
+        - vendor/autoload.php
 

src/Buffer.php

@@ -16,6 +16,9 @@
 use CallbackFilterIterator;
 use Closure;
 use Iterator;
+use League\Csv\Inspection\Inspector;
+use League\Csv\Inspection\Metadata;
+use League\Csv\Inspection\Summary;
 use League\Csv\Query\Constraint\Criteria;
 use League\Csv\Query\Predicate;
 use League\Csv\Serializer\Denormalizer;
@@ -203,6 +206,35 @@ public function map(callable $callback): Iterator
         return MapIterator::fromIterable($this->getRecords(), $callback);
     }
 
+    /**
+     * @param callable(TInitial|null, array<mixed>, array-key=): TInitial $callback
+     * @param TInitial|null $initial
+     *
+     * @template TInitial
+     *
+     * @throws SyntaxError
+     *
+     * @return TInitial|null
+     */
+    public function reduce(callable $callback, mixed $initial = null): mixed
+    {
+        foreach ($this->getRecords() as $offset => $record) {
+            $initial = $callback($initial, $record, $offset);
+        }
+
+        return $initial;
+    }
+
+    public function describe(?Inspector $inspector = null): Summary
+    {
+        return ($inspector ?? Inspector::default())->describe($this);
+    }
+
+    public function schema(?Inspector $inspector = null): Metadata
+    {
+        return ($inspector ?? Inspector::default())->schema($this);
+    }
+
     /**
      * @param non-negative-int $nth
      *

src/Inspection/Aggregator.php

@@ -0,0 +1,48 @@
+<?php
+
+/**
+ * League.Csv (https://csv.thephpleague.com)
+ *
+ * (c) Ignace Nyamagana Butera <nyamsprod@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace League\Csv\Inspection;
+
+use Generator;
+use IteratorAggregate;
+use SplQueue;
+
+final class Aggregator implements IteratorAggregate
+{
+    private SplQueue $queue;
+    private bool $finished = false;
+
+    public function __construct()
+    {
+        $this->queue = new SplQueue();
+    }
+
+    public function push(mixed $value): void
+    {
+        $this->queue->enqueue($value);
+    }
+
+    public function finish(): void
+    {
+        $this->finished = true;
+    }
+
+    public function getIterator(): Generator
+    {
+        while (!$this->finished || !$this->queue->isEmpty()) {
+            if (!$this->queue->isEmpty()) {
+                yield $this->queue->dequeue();
+            }
+        }
+    }
+}

src/Inspection/Calculator/FieldCalculator.php

@@ -0,0 +1,30 @@
+<?php
+
+/**
+ * League.Csv (https://csv.thephpleague.com)
+ *
+ * (c) Ignace Nyamagana Butera <nyamsprod@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace League\Csv\Inspection\Calculator;
+
+use League\Csv\Inspection\Strategy\FieldStrategy;
+
+interface FieldCalculator
+{
+    /** @return non-empty-string */
+    public function name(): string;
+
+    public function push(mixed $value): void;
+
+    public function calculate(): mixed;
+
+    public function reset(): void;
+
+    public function supports(FieldStrategy $strategy): bool;
+}

src/Inspection/Calculator/MaxFieldCalculator.php

@@ -0,0 +1,91 @@
+<?php
+
+/**
+ * League.Csv (https://csv.thephpleague.com)
+ *
+ * (c) Ignace Nyamagana Butera <nyamsprod@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace League\Csv\Inspection\Calculator;
+
+use DateTimeInterface;
+use League\Csv\Inspection\Strategy\DateFieldStrategy;
+use League\Csv\Inspection\Strategy\FieldStrategy;
+use League\Csv\Inspection\Strategy\NumericFieldStrategy;
+use ValueError;
+
+use function is_numeric;
+use function trim;
+
+final class MaxFieldCalculator implements FieldCalculator
+{
+    /** @var non-empty-string */
+    public readonly string $name;
+    /** @var DateTimeInterface|float|null */
+    private mixed $value;
+    private ?string $type;
+
+    public function __construct(string $name = 'max')
+    {
+        '' !== ($name = trim($name)) || throw new ValueError('The calculator name cannot be empty.');
+        $this->name = $name;
+        $this->reset();
+    }
+
+    public function supports(FieldStrategy $strategy): bool
+    {
+        return match ($strategy::class) {
+            NumericFieldStrategy::class,
+            DateFieldStrategy::class => true,
+            default => false,
+        };
+    }
+
+    public function reset(): void
+    {
+        $this->value = null;
+        $this->type = null;
+    }
+
+    public function name(): string
+    {
+        return $this->name;
+    }
+
+    public function push(mixed $value): void
+    {
+        $type = null;
+        if (is_numeric($value)) {
+            $type = 'numeric';
+            $value = (float) $value;
+        } elseif ($value instanceof DateTimeInterface) {
+            $type = 'date';
+        }
+
+        if (null === $type) {
+            return;
+        }
+
+        $this->type ??= $type;
+        if ($type !== $this->type) {
+            return;
+        }
+
+        if (null === $this->value || $value > $this->value) {
+            $this->value = $value;
+        }
+    }
+
+    /**
+     * @return DateTimeInterface|float|null
+     */
+    public function calculate(): mixed
+    {
+        return $this->value;
+    }
+}

src/Inspection/Calculator/MinFieldCalculator.php

@@ -0,0 +1,88 @@
+<?php
+
+/**
+ * League.Csv (https://csv.thephpleague.com)
+ *
+ * (c) Ignace Nyamagana Butera <nyamsprod@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace League\Csv\Inspection\Calculator;
+
+use DateTimeInterface;
+use League\Csv\Inspection\Strategy\DateFieldStrategy;
+use League\Csv\Inspection\Strategy\FieldStrategy;
+use League\Csv\Inspection\Strategy\NumericFieldStrategy;
+use ValueError;
+
+use function is_numeric;
+use function trim;
+
+final class MinFieldCalculator implements FieldCalculator
+{
+    /** @var non-empty-string */
+    public readonly string $name;
+    /** @var DateTimeInterface|float|null */
+    private mixed $value;
+    private ?string $type;
+
+    public function __construct(string $name = 'min')
+    {
+        '' !== ($name = trim($name)) || throw new ValueError('The calculator name cannot be empty.');
+        $this->name = $name;
+        $this->reset();
+    }
+
+    public function reset(): void
+    {
+        $this->value = null;
+        $this->type = null;
+    }
+
+    public function name(): string
+    {
+        return $this->name;
+    }
+
+    public function supports(FieldStrategy $strategy): bool
+    {
+        return match ($strategy::class) {
+            NumericFieldStrategy::class,
+            DateFieldStrategy::class => true,
+            default => false,
+        };
+    }
+
+    public function push(mixed $value): void
+    {
+        $type = null;
+        if (is_numeric($value)) {
+            $type = 'numeric';
+            $value = (float) $value;
+        } elseif ($value instanceof DateTimeInterface) {
+            $type = 'date';
+        }
+
+        if (null === $type) {
+            return;
+        }
+
+        $this->type ??= $type;
+        if ($type !== $this->type) {
+            return;
+        }
+
+        if (null === $this->value || $value < $this->value) {
+            $this->value = $value;
+        }
+    }
+
+    public function calculate(): mixed
+    {
+        return $this->value;
+    }
+}