Add argument to is_pipeline to set return value for empty pipeline

Necessary to handle non-array values

Author: GromNaN

src/Operation/BulkWrite.php

@@ -228,7 +228,7 @@ public function __construct(string $databaseName, string $collectionName, array
                         throw InvalidArgumentException::invalidType(sprintf('$operations[%d]["%s"][1]', $i, $type), $args[1], 'array or object');
                     }
 
-                    if ($args[1] === [] || ! is_first_key_operator($args[1]) && ! is_pipeline($args[1])) {
+                    if (! is_first_key_operator($args[1]) && ! is_pipeline($args[1], false)) {
                         throw new InvalidArgumentException(sprintf('First key in $operations[%d]["%s"][1] is neither an update operator nor a pipeline', $i, $type));
                     }
 

src/Operation/FindOneAndUpdate.php

@@ -113,7 +113,7 @@ public function __construct(string $databaseName, string $collectionName, $filte
             throw InvalidArgumentException::invalidType('$update', $update, 'array or object');
         }
 
-        if ($update === [] || ! is_first_key_operator($update) && ! is_pipeline($update)) {
+        if (! is_first_key_operator($update) && ! is_pipeline($update, false)) {
             throw new InvalidArgumentException('Expected an update document with operator as first key or a pipeline');
         }
 

src/Operation/ReplaceOne.php

@@ -89,7 +89,7 @@ public function __construct(string $databaseName, string $collectionName, $filte
             throw new InvalidArgumentException('First key in $replacement argument is an update operator');
         }
 
-        if ($replacement === [] || is_pipeline($replacement)) {
+        if (is_pipeline($replacement, false)) {
             throw new InvalidArgumentException('$replacement argument is a pipeline');
         }
 

src/Operation/Update.php

@@ -147,7 +147,7 @@ public function __construct(string $databaseName, string $collectionName, $filte
             throw InvalidArgumentException::invalidType('"multi" option', $options['multi'], 'boolean');
         }
 
-        if ($options['multi'] && ($update === [] || ! is_first_key_operator($update) && ! is_pipeline($update))) {
+        if ($options['multi'] && ! is_first_key_operator($update) && ! is_pipeline($update, false)) {
             throw new InvalidArgumentException('"multi" option cannot be true if $update is a replacement document');
         }
 

src/Operation/UpdateMany.php

@@ -88,7 +88,7 @@ public function __construct(string $databaseName, string $collectionName, $filte
             throw InvalidArgumentException::invalidType('$update', $update, 'array or object');
         }
 
-        if ($update === [] || ! is_first_key_operator($update) && ! is_pipeline($update)) {
+        if (! is_first_key_operator($update) && ! is_pipeline($update, false)) {
             throw new InvalidArgumentException('Expected an update document with operator as first key or a pipeline');
         }
 

src/Operation/UpdateOne.php

@@ -88,7 +88,7 @@ public function __construct(string $databaseName, string $collectionName, $filte
             throw InvalidArgumentException::invalidType('$update', $update, 'array or object');
         }
 
-        if ($update === [] || ! is_first_key_operator($update) && ! is_pipeline($update)) {
+        if (! is_first_key_operator($update) && ! is_pipeline($update, false)) {
             throw new InvalidArgumentException('Expected an update document with operator as first key or a pipeline');
         }
 

src/functions.php

@@ -223,7 +223,7 @@ function is_first_key_operator($document): bool
  * @param array|object $pipeline
  * @throws InvalidArgumentException
  */
-function is_pipeline($pipeline): bool
+function is_pipeline($pipeline, bool $emptyIsValid = true): bool
 {
     if ($pipeline instanceof PackedArray) {
         /* Nested documents and arrays are intentionally left as BSON. We avoid
@@ -244,7 +244,7 @@ function is_pipeline($pipeline): bool
     }
 
     if ($pipeline === []) {
-        return true;
+        return $emptyIsValid;
     }
 
     $expectedKey = 0;

tests/FunctionsTest.php

@@ -243,9 +243,9 @@ public function testIsLastPipelineOperatorWrite(callable $cast): void
     }
 
     /** @dataProvider providePipelines */
-    public function testIsPipeline($expected, $pipeline): void
+    public function testIsPipeline($expected, $pipeline, $emptyIsValid = true): void
     {
-        $this->assertSame($expected, is_pipeline($pipeline));
+        $this->assertSame($expected, is_pipeline($pipeline, $emptyIsValid));
     }
 
     public function providePipelines(): array
@@ -265,7 +265,6 @@ public function providePipelines(): array
 
         return [
             // Valid pipeline in various forms
-            'valid: empty array' => [true, []],
             'valid: array' => [true, $valid],
             'valid: Serializable' => [true, new BSONArray($valid)],
             'valid: PackedArray' => [true, PackedArray::fromPHP($valid)],
@@ -287,9 +286,12 @@ public function providePipelines(): array
             'invalid pipeline element type: Serializable' => [false, new BSONArray([new BSONArray([])])],
             'invalid pipeline element type: PackedArray' => [false, PackedArray::fromPHP([[]])],
             // Empty array has no pipeline stages
-            'invalid empty: array' => [false, []],
-            'invalid empty: Serializable' => [false, new BSONArray([])],
-            'invalid empty: PackedArray' => [false, PackedArray::fromPHP([])],
+            'valid empty: array' => [true, []],
+            'valid empty: Serializable' => [true, new BSONArray([])],
+            'valid empty: PackedArray' => [true, PackedArray::fromPHP([])],
+            'invalid empty: array' => [false, [], false],
+            'invalid empty: Serializable' => [false, new BSONArray([]), false],
+            'invalid empty: PackedArray' => [false, PackedArray::fromPHP([]), false],
             // False positive: DBRef in numeric field
             'false positive DBRef: array' => [true, $dbrefInNumericField],
             'false positive DBRef: Serializable' => [true, new BSONArray($dbrefInNumericField)],