Added isSampled to Context, delegate isSmapled to Context from Span

Author: allflame

src/Span/Context/SpanContext.php

@@ -44,6 +44,11 @@ public function getParentId(): int
         return $this->parentId;
     }
 
+    public function isSampled(): bool
+    {
+        return (bool)($this->flags & 0x01);
+    }
+
     public function isDebug(): bool
     {
         return (bool)($this->flags & 0x02);

src/Span/Span.php

@@ -33,7 +33,6 @@ public function __construct(
         $this->flags = $context->getFlags();
         $this->operationName = $operationName;
         $this->startTime = $startTime;
-
         $this->tags = $tags;
         $this->logs = $logs;
         parent::__construct();
@@ -42,14 +41,11 @@ public function __construct(
     public function __destruct()
     {
         if (null !== $this->duration) {
-            return $this;
+            return;
         }
         $this->tags[] = new ErrorTag();
         $this->tags[] = new OutOfScopeTag();
-
         $this->tracer->finish($this);
-
-        return $this;
     }
 
     public function getContext(): ?SpanContext
@@ -59,7 +55,7 @@ public function getContext(): ?SpanContext
 
     public function isSampled(): bool
     {
-        return (bool)($this->flags & 1);
+        return $this->context->isSampled();
     }
 
     public function start(int $startTimeUsec): SpanInterface