Drop PHP 7.4 support (#1244)

* drop php 7.4 support
update composer.json minimums, and run rector over the code to update what it can. changed some static analysis
config to fix some rector-induced failures.

* adding union typehints

* reformat constructor property promotions

* updating/removing phpdoc

* suppress protobuf extension complaint
submitted a PR upstream to fix phan stubs

* don't validate packages against 7.4

* remove php8 polyfill

* fix readonly comments

* apply trailing commas to multiline fixer
upgrade php-cs-fixer, and apply a new rule for multiline comments

* remove unreachable default match arms for protobuf serializer

* adding more union types to vars

* use weakmap directly

* remove handling for not-supported WeakMap

* spacing

Author: brettmc

Context.php

@@ -39,6 +39,7 @@ public static function createKey(string $key): ContextKeyInterface
 
     /**
      * @param ContextStorageInterface&ExecutionContextAwareInterface $storage
+     * @todo update type-hint (php >= 8.1)
      */
     public static function setStorage(ContextStorageInterface $storage): void
     {
@@ -47,6 +48,7 @@ public static function setStorage(ContextStorageInterface $storage): void
 
     /**
      * @return ContextStorageInterface&ExecutionContextAwareInterface
+     * @todo update return type-hint (php >= 8.1)
      */
     public static function storage(): ContextStorageInterface
     {
@@ -55,11 +57,9 @@ public static function storage(): ContextStorageInterface
     }
 
     /**
-     * @param ContextInterface|false|null $context
-     *
      * @internal OpenTelemetry
      */
-    public static function resolve($context, ?ContextStorageInterface $contextStorage = null): ContextInterface
+    public static function resolve(ContextInterface|false|null $context, ?ContextStorageInterface $contextStorage = null): ContextInterface
     {
         return $context
             ?? ($contextStorage ?? self::storage())->current()

ContextKey.php

@@ -9,11 +9,8 @@
  */
 final class ContextKey implements ContextKeyInterface
 {
-    private ?string $name;
-
-    public function __construct(?string $name=null)
+    public function __construct(private ?string $name = null)
     {
-        $this->name = $name;
     }
 
     public function name(): ?string

ContextStorageHead.php

@@ -9,11 +9,9 @@
  */
 final class ContextStorageHead
 {
-    public ContextStorage $storage;
     public ?ContextStorageNode $node = null;
 
-    public function __construct(ContextStorage $storage)
+    public function __construct(public ContextStorage $storage)
     {
-        $this->storage = $storage;
     }
 }

ContextStorageNode.php

@@ -11,19 +11,13 @@
  */
 final class ContextStorageNode implements ScopeInterface, ContextStorageScopeInterface
 {
-    public ContextInterface $context;
-    public ContextStorageHead $head;
-    private ?ContextStorageNode $previous;
     private array $localStorage = [];
 
     public function __construct(
-        ContextInterface $context,
-        ContextStorageHead $head,
-        ?ContextStorageNode $previous = null
+        public ContextInterface $context,
+        public ContextStorageHead $head,
+        private ?ContextStorageNode $previous = null,
     ) {
-        $this->context = $context;
-        $this->head = $head;
-        $this->previous = $previous;
     }
 
     public function offsetExists($offset): bool
@@ -76,8 +70,8 @@ public function detach(): int
 
         assert($this->head->node !== null);
         for ($n = $this->head->node, $depth = 1;
-             $n->previous !== $this;
-             $n = $n->previous, $depth++) {
+            $n->previous !== $this;
+            $n = $n->previous, $depth++) {
             assert($n->previous !== null);
         }
         $n->previous = $this->previous;

DebugScope.php

@@ -24,15 +24,12 @@ final class DebugScope implements ScopeInterface
 {
     private static bool $shutdownHandlerInitialized = false;
     private static bool $finalShutdownPhase = false;
-
-    private ContextStorageScopeInterface $scope;
     private ?int $fiberId;
     private array $createdAt;
     private ?array $detachedAt = null;
 
-    public function __construct(ContextStorageScopeInterface $scope)
+    public function __construct(private ContextStorageScopeInterface $scope)
     {
-        $this->scope = $scope;
         $this->fiberId = self::currentFiberId();
         $this->createdAt = debug_backtrace(DEBUG_BACKTRACE_IGNORE_ARGS);
 

FiberBoundContextStorage.php

@@ -20,15 +20,11 @@
  */
 final class FiberBoundContextStorage implements ContextStorageInterface, ExecutionContextAwareInterface
 {
-    /** @var ContextStorageInterface&ExecutionContextAwareInterface */
-    private ContextStorageInterface $storage;
-
     /**
      * @param ContextStorageInterface&ExecutionContextAwareInterface $storage
      */
-    public function __construct(ContextStorageInterface $storage)
+    public function __construct(private ContextStorageInterface $storage)
     {
-        $this->storage = $storage;
     }
 
     public function fork($id): void

FiberBoundContextStorageScope.php

@@ -18,11 +18,8 @@
  */
 final class FiberBoundContextStorageScope implements ScopeInterface, ContextStorageScopeInterface
 {
-    private ContextStorageScopeInterface $scope;
-
-    public function __construct(ContextStorageScopeInterface $scope)
+    public function __construct(private ContextStorageScopeInterface $scope)
     {
-        $this->scope = $scope;
     }
 
     public function offsetExists($offset): bool

Propagation/ArrayAccessGetterSetter.php

@@ -6,11 +6,8 @@
 
 use function array_key_first;
 use ArrayAccess;
-use function get_class;
-use function gettype;
 use InvalidArgumentException;
 use function is_array;
-use function is_object;
 use function is_string;
 use function sprintf;
 use function strcasecmp;
@@ -53,7 +50,7 @@ public function keys($carrier): array
         throw new InvalidArgumentException(
             sprintf(
                 'Unsupported carrier type: %s.',
-                is_object($carrier) ? get_class($carrier) : gettype($carrier),
+                get_debug_type($carrier),
             )
         );
     }
@@ -75,7 +72,7 @@ public function get($carrier, string $key): ?string
         throw new InvalidArgumentException(
             sprintf(
                 'Unsupported carrier type: %s. Unable to get value associated with key:%s',
-                is_object($carrier) ? get_class($carrier) : gettype($carrier),
+                get_debug_type($carrier),
                 $key
             )
         );
@@ -100,7 +97,7 @@ public function set(&$carrier, string $key, string $value): void
         throw new InvalidArgumentException(
             sprintf(
                 'Unsupported carrier type: %s. Unable to set value associated with key:%s',
-                is_object($carrier) ? get_class($carrier) : gettype($carrier),
+                get_debug_type($carrier),
                 $key
             )
         );

Propagation/MultiTextMapPropagator.php

@@ -15,14 +15,6 @@ final class MultiTextMapPropagator implements TextMapPropagatorInterface
 {
     /**
      * @readonly
-     *
-     * @var list<TextMapPropagatorInterface>
-     */
-    private array $propagators = [];
-
-    /**
-     * @readonly
-     *
      * @var list<string>
      */
     private array $fields;
@@ -32,10 +24,11 @@ final class MultiTextMapPropagator implements TextMapPropagatorInterface
      *
      * @param list<TextMapPropagatorInterface> $propagators
      */
-    public function __construct(array $propagators)
-    {
-        $this->propagators = $propagators;
-        $this->fields = $this->extractFields($propagators);
+    public function __construct(
+        /** @readonly */
+        private array $propagators,
+    ) {
+        $this->fields = $this->extractFields($this->propagators);
     }
 
     public function fields(): array

Propagation/SanitizeCombinedHeadersPropagationGetter.php

@@ -18,11 +18,8 @@ final class SanitizeCombinedHeadersPropagationGetter implements PropagationGette
     private const SERVER_CONCAT_HEADERS_REGEX = '/;(?=[^,=;]*=|$)/';
     private const TRAILING_LEADING_SEPARATOR_REGEX = '/^' . self::LIST_MEMBERS_SEPARATOR . '+|' . self::LIST_MEMBERS_SEPARATOR . '+$/';
 
-    private PropagationGetterInterface $getter;
-
-    public function __construct(PropagationGetterInterface $getter)
+    public function __construct(private PropagationGetterInterface $getter)
     {
-        $this->getter = $getter;
     }
 
     public function keys($carrier): array