feat(tracing): Add a method to get transaction for given span: GetTransaction()

tracing.go

@@ -241,6 +241,26 @@ func (s *Span) IsTransaction() bool {
 	return s.isTransaction
 }
 
+// GetTransaction returns the transaction that contains this span.
+//
+// For transaction spans it returns itself. For spans that were created manually
+// the method returns "nil".
+func (s *Span) GetTransaction() *Span {
+	spanRecorder := s.spanRecorder()
+	if spanRecorder == nil {
+		// This probably means that the Span was created manually (not via
+		// StartTransaction/StartSpan or StartChild).
+		// Return "nil" to indicate that it's not a normal situation.
+		return nil
+	}
+	recorderRoot := spanRecorder.root()
+	if recorderRoot == nil {
+		// Same as above: manually created Span.
+		return nil
+	}
+	return recorderRoot
+}
+
 // TODO(tracing): maybe add shortcuts to get/set transaction name. Right now the
 // transaction name is in the Scope, as it has existed there historically, prior
 // to tracing.

tracing_test.go

@@ -764,6 +764,7 @@ func TestParseTraceParentContext(t *testing.T) {
 	}
 
 	for _, tt := range tests {
+		tt := tt
 		t.Run(tt.name, func(t *testing.T) {
 			traceParentContext, valid := ParseTraceParentContext([]byte(tt.sentryTrace))
 
@@ -776,3 +777,36 @@ func TestParseTraceParentContext(t *testing.T) {
 		})
 	}
 }
+
+func TestGetTransactionWithProperTransactionsSpans(t *testing.T) {
+	ctx := NewTestContext(ClientOptions{
+		EnableTracing: true,
+	})
+	transaction := StartTransaction(ctx, "transaction")
+	child1 := transaction.StartChild("child1")
+	child2 := transaction.StartChild("child2")
+	grandchild := child1.StartChild("grandchild")
+
+	assertEqual(t, transaction.GetTransaction(), transaction)
+	assertEqual(t, child1.GetTransaction(), transaction)
+	assertEqual(t, child2.GetTransaction(), transaction)
+	assertEqual(t, grandchild.GetTransaction(), transaction)
+
+	// Another transaction, unrelated to the first one
+	anotherTransaction := StartTransaction(ctx, "another transaction")
+
+	assertNotEqual(t, transaction, anotherTransaction)
+	assertEqual(t, anotherTransaction.GetTransaction(), anotherTransaction)
+}
+
+func TestGetTransactionReturnsNilOnManuallyCreatedSpans(t *testing.T) {
+	span1 := Span{}
+	if span1.GetTransaction() != nil {
+		t.Errorf("GetTransaction() should return nil on manually created Spans")
+	}
+
+	span2 := Span{isTransaction: true}
+	if span2.GetTransaction() != nil {
+		t.Errorf("GetTransaction() should return nil on manually created Spans")
+	}
+}