Handle string callable in case of non-static method

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 
+- Fix deprecation raised when serializing callable in certain circumstances (#821)
+
 ## 2.2.0 (2019-09-23)
 
 - Change type hint for both parameter and return value of `HubInterface::getCurrentHub` and `HubInterface::setCurrentHub()` methods (#849)

composer.json

@@ -74,7 +74,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-develop": "2.2-dev"
+            "dev-develop": "2.3-dev"
         }
     }
 }

src/Serializer/AbstractSerializer.php

@@ -20,6 +20,7 @@
 
 namespace Sentry\Serializer;
 
+use Sentry\Exception\InvalidArgumentException;
 use Sentry\Options;
 
 /**
@@ -102,7 +103,7 @@ protected function serializeRecursively($value, int $_depth = 0)
             }
 
             if (\is_callable($value)) {
-                return $this->serializeCallable($value);
+                return $this->serializeCallableWithoutTypeHint($value);
             }
 
             if (\is_array($value)) {
@@ -250,7 +251,7 @@ protected function serializeValue($value)
         }
 
         if (\is_callable($value)) {
-            return $this->serializeCallable($value);
+            return $this->serializeCallableWithoutTypeHint($value);
         }
 
         if (\is_array($value)) {
@@ -261,17 +262,42 @@ protected function serializeValue($value)
     }
 
     /**
+     * This method is provided as a non-BC upgrade of serializeCallable,
+     * since using the callable type raises a deprecation in some cases.
+     *
+     * @param callable $callable
+     *
+     * @return string
+     */
+    protected function serializeCallableWithoutTypeHint($callable): string
+    {
+        $this->assertIsValidCallable($callable);
+
+        if (\is_string($callable) && !\function_exists($callable)) {
+            return $callable;
+        }
+
+        return $this->serializeCallable($callable);
+    }
+
+    /**
+     * Use serializeCallableWithoutTypeHint instead (no type in argument).
+     *
+     * @see https://github.com/getsentry/sentry-php/pull/821
+     *
      * @param callable $callable
      *
      * @return string
      */
-    protected function serializeCallable(callable $callable): string
+    protected function serializeCallable(/* callable type to be removed in 3.0, see #821 => */callable $callable): string
     {
+        $this->assertIsValidCallable($callable);
+
         try {
             if (\is_array($callable)) {
                 $reflection = new \ReflectionMethod($callable[0], $callable[1]);
                 $class = $reflection->getDeclaringClass();
-            } elseif ($callable instanceof \Closure || \is_string($callable)) {
+            } elseif ($callable instanceof \Closure || (\is_string($callable) && \function_exists($callable))) {
                 $reflection = new \ReflectionFunction($callable);
                 $class = null;
             } elseif (\is_object($callable) && method_exists($callable, '__invoke')) {
@@ -357,4 +383,21 @@ public function getSerializeAllObjects(): bool
     {
         return $this->serializeAllObjects;
     }
+
+    /**
+     * @param mixed $callable
+     *
+     * @throws InvalidArgumentException
+     */
+    private function assertIsValidCallable($callable): void
+    {
+        if (!\is_callable($callable)) {
+            throw new InvalidArgumentException(sprintf(
+                'Expecting callable, got %s',
+                \is_object($callable)
+                    ? \get_class($callable)
+                    : \gettype($callable)
+            ));
+        }
+    }
 }

tests/Serializer/AbstractSerializerTest.php

@@ -455,13 +455,17 @@ public function serializableCallableProvider(): array
                 'callable' => $callableWithoutNamespaces,
                 'expected' => 'Lambda void {closure} [int|null param1_70ns]',
             ],
+            [
+                'callable' => __METHOD__,
+                'expected' => __METHOD__,
+            ],
         ];
     }
 
     /**
      * @dataProvider serializableCallableProvider
      */
-    public function testSerializeCallable(callable $callable, string $expected): void
+    public function testSerializeCallable($callable, string $expected): void
     {
         $serializer = $this->createSerializer();
         $actual = $this->invokeSerialization($serializer, $callable);