From 63e3107a767f140dbe9ffa4a16137b98288f13f6 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Fri, 28 Nov 2025 16:13:28 +0100
Subject: [PATCH 01/16] Update

---
 packages/dart/lib/src/hub.dart                | 47 +++++++++++++++++--
 .../dart/lib/src/protocol/simple_span.dart    |  5 ++
 packages/dart/lib/src/scope.dart              | 34 ++++++++++++++
 3 files changed, 83 insertions(+), 3 deletions(-)

diff --git a/packages/dart/lib/src/hub.dart b/packages/dart/lib/src/hub.dart
index be2d4ddd5f..88e8cb2420 100644
--- a/packages/dart/lib/src/hub.dart
+++ b/packages/dart/lib/src/hub.dart
@@ -11,6 +11,7 @@ import 'protocol/unset_span.dart';
 import 'sentry_tracer.dart';
 import 'sentry_traces_sampler.dart';
 import 'protocol/noop_span.dart';
+import 'protocol/simple_span.dart';
 import 'transport/data_category.dart';
 
 /// Configures the scope through the callback.
@@ -586,12 +587,52 @@ class Hub {
         SentryLevel.warning,
         "Instance is disabled and this 'startSpan' call is a no-op.",
       );
-    } else if (_options.isTracingEnabled()) {
-      // TODO: implementation of span api behaviour according to https://develop.sentry.dev/sdk/telemetry/spans/span-api/
       return NoOpSpan();
     }
 
-    return NoOpSpan();
+    if (!_options.isTracingEnabled()) {
+      return NoOpSpan();
+    }
+
+    // Determine the parent span based on the parentSpan parameter:
+    // - If parentSpan is UnsetSpan (default), use the currently active span
+    // - If parentSpan is a specific Span, use that as the parent
+    // - If parentSpan is null, create a root/segment span (no parent)
+    // ignore: unused_local_variable
+    final Span? resolvedParentSpan;
+    if (parentSpan is UnsetSpan) {
+      // Use the currently active span from scope as parent
+      resolvedParentSpan = scope.getActiveSpan();
+    } else {
+      // Use the explicitly provided parent (can be null for root/segment span)
+      resolvedParentSpan = parentSpan;
+    }
+
+    final span = SimpleSpan(parentSpan: resolvedParentSpan, hub: this);
+
+    span.setName(name);
+    if (attributes != null) {
+      span.setAttributes(attributes);
+    }
+    if (active) {
+      scope.setActiveSpan(span);
+    }
+
+    return span;
+  }
+
+  void captureSpan(Span span) {
+    if (!_isEnabled) {
+      _options.log(
+        SentryLevel.warning,
+        "Instance is disabled and this 'captureSpan' call is a no-op.",
+      );
+      return;
+    }
+
+    scope.removeActiveSpan(span);
+
+    // TODO: implement span buffer and add the span to the buffer
   }
 
   @internal
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index dc31156916..c56f65b9b9 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -1,6 +1,11 @@
 import '../../sentry.dart';
 
 class SimpleSpan implements Span {
+  final Hub hub;
+  final Span? parentSpan;
+
+  SimpleSpan({required this.parentSpan, required this.hub});
+
   @override
   void end({DateTime? endTimestamp}) {
     // TODO: implement end
diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index 6024022210..051c6dedf4 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -43,6 +43,40 @@ class Scope {
   /// Returns active transaction or null if there is no active transaction.
   ISentrySpan? span;
 
+  final List<Span> _activeSpans = [];
+
+  /// Returns the currently active span, or `null` if no span is active.
+  ///
+  /// The active span is the most recently set span via [setActiveSpan].
+  /// When starting a new span with `active: true` (the default), the new span
+  /// becomes a child of this active span.
+  @internal
+  Span? getActiveSpan() {
+    return _activeSpans.isNotEmpty ? _activeSpans.last : null;
+  }
+
+  /// Sets the given [span] as the currently active span.
+  ///
+  /// Active spans are used to automatically parent new spans.
+  /// When a new span is started with `active: true` (the default), it becomes
+  /// a child of the currently active span.
+  ///
+  /// The active spans are maintained as a stack - the most recently set span
+  /// is the current active span.
+  @internal
+  void setActiveSpan(Span span) {
+    _activeSpans.add(span);
+  }
+
+  /// Removes the given [span] from the active spans list.
+  ///
+  /// This should be called when a span ends to remove it from the active
+  /// span hierarchy.
+  @internal
+  void removeActiveSpan(Span span) {
+    _activeSpans.remove(span);
+  }
+
   /// The propagation context for connecting errors and spans to traces.
   /// There should always be a propagation context available at all times.
   ///

From eb0cdefae564b12c5b24cdccbb72b4baca538f2e Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 11:18:34 +0100
Subject: [PATCH 02/16] Updateg

---
 packages/dart/lib/src/hub_adapter.dart        |  3 ++
 packages/dart/lib/src/noop_hub.dart           |  3 ++
 .../dart/lib/src/protocol/simple_span.dart    |  2 +-
 packages/dart/lib/src/scope.dart              |  3 ++
 packages/dart/test/scope_test.dart            | 41 +++++++++++++++++++
 5 files changed, 51 insertions(+), 1 deletion(-)

diff --git a/packages/dart/lib/src/hub_adapter.dart b/packages/dart/lib/src/hub_adapter.dart
index 1203bcc1f3..1e9ddf4425 100644
--- a/packages/dart/lib/src/hub_adapter.dart
+++ b/packages/dart/lib/src/hub_adapter.dart
@@ -221,4 +221,7 @@ class HubAdapter implements Hub {
 
   @override
   void removeAttribute(String key) => Sentry.currentHub.removeAttribute(key);
+
+  @override
+  void captureSpan(Span span) => Sentry.currentHub.captureSpan(span);
 }
diff --git a/packages/dart/lib/src/noop_hub.dart b/packages/dart/lib/src/noop_hub.dart
index 6e8845a84f..44b1c82f87 100644
--- a/packages/dart/lib/src/noop_hub.dart
+++ b/packages/dart/lib/src/noop_hub.dart
@@ -161,4 +161,7 @@ class NoOpHub implements Hub {
     Map<String, SentryAttribute>? attributes,
   }) =>
       NoOpSpan();
+
+  @override
+  void captureSpan(Span span) {}
 }
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index c56f65b9b9..6ba0d70490 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -4,7 +4,7 @@ class SimpleSpan implements Span {
   final Hub hub;
   final Span? parentSpan;
 
-  SimpleSpan({required this.parentSpan, required this.hub});
+  SimpleSpan({required this.parentSpan, Hub? hub}) : hub = hub ?? HubAdapter();
 
   @override
   void end({DateTime? endTimestamp}) {
diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index 051c6dedf4..c6679e4d6d 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -45,6 +45,9 @@ class Scope {
 
   final List<Span> _activeSpans = [];
 
+  @visibleForTesting
+  List<Span> get activeSpans => List.unmodifiable(_activeSpans);
+
   /// Returns the currently active span, or `null` if no span is active.
   ///
   /// The active span is the most recently set span via [setActiveSpan].
diff --git a/packages/dart/test/scope_test.dart b/packages/dart/test/scope_test.dart
index 44683f1c50..78853d3853 100644
--- a/packages/dart/test/scope_test.dart
+++ b/packages/dart/test/scope_test.dart
@@ -2,6 +2,7 @@
 
 import 'package:collection/collection.dart';
 import 'package:sentry/sentry.dart';
+import 'package:sentry/src/protocol/simple_span.dart';
 import 'package:sentry/src/sentry_tracer.dart';
 import 'package:test/test.dart';
 
@@ -352,6 +353,46 @@ void main() {
     expect(sut.extra['test'], null);
   });
 
+  test('setActiveSpan adds span to active span list', () {
+    final sut = fixture.getSut();
+
+    final span = SimpleSpan(parentSpan: null);
+    final span2 = SimpleSpan(parentSpan: null);
+    sut.setActiveSpan(span);
+    sut.setActiveSpan(span2);
+
+    expect(sut.activeSpans.length, 2);
+    expect(sut.activeSpans.last, span2);
+  });
+
+  test('getActiveSpan returns the last active span in the list', () {
+    final sut = fixture.getSut();
+
+    final span = SimpleSpan(parentSpan: null);
+    final span2 = SimpleSpan(parentSpan: null);
+    sut.setActiveSpan(span);
+    sut.setActiveSpan(span2);
+
+    final activeSpan = sut.getActiveSpan();
+    expect(activeSpan, span2);
+  });
+
+  test(
+      'removeActiveSpan removes the active span in the list regardless of order',
+      () {
+    final sut = fixture.getSut();
+
+    final span = SimpleSpan(parentSpan: null);
+    final span2 = SimpleSpan(parentSpan: null);
+    sut.setActiveSpan(span);
+    sut.setActiveSpan(span2);
+
+    sut.removeActiveSpan(span);
+
+    expect(sut.activeSpans.length, 1);
+    expect(sut.activeSpans.first, span2);
+  });
+
   test('clears $Scope', () {
     final sut = fixture.getSut();
 

From 19a8c19fa8d19fca6ee8ce64ec1343016460e04c Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 15:12:12 +0100
Subject: [PATCH 03/16] Update

---
 packages/dart/lib/src/hub.dart                |   5 +-
 packages/dart/lib/src/protocol/noop_span.dart |   6 +
 .../dart/lib/src/protocol/simple_span.dart    |   8 +-
 packages/dart/lib/src/protocol/span.dart      |   7 +
 .../dart/lib/src/protocol/unset_span.dart     |   8 +
 packages/dart/test/hub_span_test.dart         | 193 ++++++++++++++++++
 packages/dart/test/scope_test.dart            |  12 +-
 packages/dart/test/span_test.dart             | 138 +++++++++++++
 8 files changed, 367 insertions(+), 10 deletions(-)
 create mode 100644 packages/dart/test/hub_span_test.dart
 create mode 100644 packages/dart/test/span_test.dart

diff --git a/packages/dart/lib/src/hub.dart b/packages/dart/lib/src/hub.dart
index 88e8cb2420..f8bfbc14f2 100644
--- a/packages/dart/lib/src/hub.dart
+++ b/packages/dart/lib/src/hub.dart
@@ -608,9 +608,8 @@ class Hub {
       resolvedParentSpan = parentSpan;
     }
 
-    final span = SimpleSpan(parentSpan: resolvedParentSpan, hub: this);
-
-    span.setName(name);
+    final span =
+        SimpleSpan(name: name, parentSpan: resolvedParentSpan, hub: this);
     if (attributes != null) {
       span.setAttributes(attributes);
     }
diff --git a/packages/dart/lib/src/protocol/noop_span.dart b/packages/dart/lib/src/protocol/noop_span.dart
index 80b8b611a1..ef55a4410c 100644
--- a/packages/dart/lib/src/protocol/noop_span.dart
+++ b/packages/dart/lib/src/protocol/noop_span.dart
@@ -3,6 +3,12 @@ import '../../sentry.dart';
 class NoOpSpan implements Span {
   const NoOpSpan();
 
+  @override
+  String get name => '';
+
+  @override
+  Span? get parentSpan => null;
+
   @override
   void end({DateTime? endTimestamp}) {}
 
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index 6ba0d70490..c43555fe29 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -2,9 +2,15 @@ import '../../sentry.dart';
 
 class SimpleSpan implements Span {
   final Hub hub;
+
+  @override
   final Span? parentSpan;
 
-  SimpleSpan({required this.parentSpan, Hub? hub}) : hub = hub ?? HubAdapter();
+  @override
+  final String name;
+
+  SimpleSpan({required this.name, required this.parentSpan, Hub? hub})
+      : hub = hub ?? HubAdapter();
 
   @override
   void end({DateTime? endTimestamp}) {
diff --git a/packages/dart/lib/src/protocol/span.dart b/packages/dart/lib/src/protocol/span.dart
index 6759ada6ea..d800b12b16 100644
--- a/packages/dart/lib/src/protocol/span.dart
+++ b/packages/dart/lib/src/protocol/span.dart
@@ -7,6 +7,13 @@ abstract class Span {
   @internal
   const Span();
 
+  /// Gets the name of the span.
+  String get name;
+
+  /// Gets the parentSpan.
+  /// If null this span has no parent.
+  Span? get parentSpan;
+
   /// Ends the span.
   ///
   /// [endTimestamp] can be used to override the end time.
diff --git a/packages/dart/lib/src/protocol/unset_span.dart b/packages/dart/lib/src/protocol/unset_span.dart
index 2dfbae74ce..164c868ed4 100644
--- a/packages/dart/lib/src/protocol/unset_span.dart
+++ b/packages/dart/lib/src/protocol/unset_span.dart
@@ -8,6 +8,14 @@ import '../../sentry.dart';
 class UnsetSpan extends Span {
   const UnsetSpan();
 
+  @override
+  String get name =>
+      throw UnimplementedError('$UnsetSpan methods should not be used');
+
+  @override
+  Span? get parentSpan =>
+      throw UnimplementedError('$UnsetSpan methods should not be used');
+
   @override
   void end({DateTime? endTimestamp}) {
     throw UnimplementedError('$UnsetSpan methods should not be used');
diff --git a/packages/dart/test/hub_span_test.dart b/packages/dart/test/hub_span_test.dart
new file mode 100644
index 0000000000..2f487393b0
--- /dev/null
+++ b/packages/dart/test/hub_span_test.dart
@@ -0,0 +1,193 @@
+import 'package:sentry/sentry.dart';
+import 'package:sentry/src/protocol/noop_span.dart';
+import 'package:sentry/src/protocol/simple_span.dart';
+import 'package:test/test.dart';
+
+import 'mocks/mock_client_report_recorder.dart';
+import 'mocks/mock_sentry_client.dart';
+import 'test_utils.dart';
+
+void main() {
+  group('Hub startSpan', () {
+    late Fixture fixture;
+
+    setUp(() {
+      fixture = Fixture();
+    });
+
+    test('startSpan returns SimpleSpan when tracing is enabled', () {
+      final hub = fixture.getSut();
+
+      final span = hub.startSpan('test-span');
+
+      expect(span, isA<SimpleSpan>());
+    });
+
+    test('startSpan returns NoOpSpan when tracing is disabled', () {
+      final hub = fixture.getSut(tracesSampleRate: null);
+
+      final span = hub.startSpan('test-span');
+
+      expect(span, isA<NoOpSpan>());
+    });
+
+    test('startSpan returns NoOpSpan when hub is disabled', () async {
+      final hub = fixture.getSut();
+      await hub.close();
+
+      final span = hub.startSpan('test-span');
+
+      expect(span, isA<NoOpSpan>());
+    });
+
+    test('startSpan sets span name', () {
+      final hub = fixture.getSut();
+
+      final span = hub.startSpan('my-span-name');
+
+      expect(span, isA<SimpleSpan>());
+      // TODO: verify span name once SimpleSpan implements it
+    });
+
+    test('startSpan with active=true sets span as active on scope', () {
+      final hub = fixture.getSut();
+
+      final span = hub.startSpan('test-span', active: true);
+
+      expect(hub.scope.getActiveSpan(), equals(span));
+    });
+
+    test('startSpan with active=false does not set span as active on scope',
+        () {
+      final hub = fixture.getSut();
+
+      hub.startSpan('test-span', active: false);
+
+      expect(hub.scope.getActiveSpan(), isNull);
+    });
+
+    test('startSpan uses active span as parent when parentSpan is not provided',
+        () {
+      final hub = fixture.getSut();
+
+      // Start first span which becomes active
+      final parentSpan = hub.startSpan('parent-span');
+      expect(hub.scope.getActiveSpan(), equals(parentSpan));
+
+      // Start second span - should use active span as parent
+      final childSpan = hub.startSpan('child-span');
+      expect(childSpan, isA<SimpleSpan>());
+      expect(childSpan.parentSpan, equals(parentSpan));
+    });
+
+    test('startSpan with explicit parentSpan uses that as parent', () {
+      final hub = fixture.getSut();
+
+      final explicitParent = hub.startSpan('explicit-parent');
+      // Start another span to change active span
+      hub.startSpan('other-span');
+
+      // Start span with explicit parent
+      final childSpan = hub.startSpan('child-span',
+          parentSpan: explicitParent, active: false);
+
+      expect(childSpan, isA<SimpleSpan>());
+      expect(childSpan.parentSpan, equals(explicitParent));
+    });
+
+    test('startSpan with parentSpan=null creates root/segment span', () {
+      final hub = fixture.getSut();
+
+      // Start active span first
+      hub.startSpan('active-span');
+
+      // Start span with null parent - should be root span
+      final rootSpan = hub.startSpan('root-span', parentSpan: null);
+
+      expect(rootSpan, isA<SimpleSpan>());
+      expect(rootSpan.parentSpan, isNull);
+    });
+
+    test('startSpan with attributes sets attributes on span', () {
+      final hub = fixture.getSut();
+      final attributes = {
+        'attr1': SentryAttribute.string('value1'),
+        'attr2': SentryAttribute.int(42),
+      };
+
+      final span = hub.startSpan('test-span', attributes: attributes);
+
+      expect(span, isA<SimpleSpan>());
+      // TODO: verify attributes once SimpleSpan implements it
+    });
+  });
+
+  group('Hub captureSpan', () {
+    late Fixture fixture;
+
+    setUp(() {
+      fixture = Fixture();
+    });
+
+    test('captureSpan removes span from active spans', () {
+      final hub = fixture.getSut();
+
+      final span = hub.startSpan('test-span');
+      expect(hub.scope.activeSpans, contains(span));
+
+      hub.captureSpan(span);
+
+      expect(hub.scope.activeSpans, isNot(contains(span)));
+    });
+
+    test('captureSpan does nothing when hub is disabled', () async {
+      final hub = fixture.getSut();
+      final span = hub.startSpan('test-span');
+      await hub.close();
+
+      // Should not throw
+      hub.captureSpan(span);
+    });
+  });
+}
+
+class Fixture {
+  final client = MockSentryClient();
+  final recorder = MockClientReportRecorder();
+
+  final options = defaultTestOptions();
+
+  SentryLevel? loggedLevel;
+  String? loggedMessage;
+  Object? loggedException;
+
+  Hub getSut({
+    double? tracesSampleRate = 1.0,
+    TracesSamplerCallback? tracesSampler,
+    bool debug = false,
+  }) {
+    options.tracesSampleRate = tracesSampleRate;
+    options.tracesSampler = tracesSampler;
+    options.debug = debug;
+    options.log = mockLogger;
+
+    final hub = Hub(options);
+
+    hub.bindClient(client);
+    options.recorder = recorder;
+
+    return hub;
+  }
+
+  void mockLogger(
+    SentryLevel level,
+    String message, {
+    String? logger,
+    Object? exception,
+    StackTrace? stackTrace,
+  }) {
+    loggedLevel = level;
+    loggedMessage = message;
+    loggedException = exception;
+  }
+}
diff --git a/packages/dart/test/scope_test.dart b/packages/dart/test/scope_test.dart
index 78853d3853..98b7892d19 100644
--- a/packages/dart/test/scope_test.dart
+++ b/packages/dart/test/scope_test.dart
@@ -356,8 +356,8 @@ void main() {
   test('setActiveSpan adds span to active span list', () {
     final sut = fixture.getSut();
 
-    final span = SimpleSpan(parentSpan: null);
-    final span2 = SimpleSpan(parentSpan: null);
+    final span = SimpleSpan(name: 'span1', parentSpan: null);
+    final span2 = SimpleSpan(name: 'span2', parentSpan: null);
     sut.setActiveSpan(span);
     sut.setActiveSpan(span2);
 
@@ -368,8 +368,8 @@ void main() {
   test('getActiveSpan returns the last active span in the list', () {
     final sut = fixture.getSut();
 
-    final span = SimpleSpan(parentSpan: null);
-    final span2 = SimpleSpan(parentSpan: null);
+    final span = SimpleSpan(name: 'span1', parentSpan: null);
+    final span2 = SimpleSpan(name: 'span2', parentSpan: null);
     sut.setActiveSpan(span);
     sut.setActiveSpan(span2);
 
@@ -382,8 +382,8 @@ void main() {
       () {
     final sut = fixture.getSut();
 
-    final span = SimpleSpan(parentSpan: null);
-    final span2 = SimpleSpan(parentSpan: null);
+    final span = SimpleSpan(name: 'span1', parentSpan: null);
+    final span2 = SimpleSpan(name: 'span2', parentSpan: null);
     sut.setActiveSpan(span);
     sut.setActiveSpan(span2);
 
diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
new file mode 100644
index 0000000000..8222977ab0
--- /dev/null
+++ b/packages/dart/test/span_test.dart
@@ -0,0 +1,138 @@
+import 'package:sentry/sentry.dart';
+import 'package:sentry/src/protocol/noop_span.dart';
+import 'package:sentry/src/protocol/simple_span.dart';
+import 'package:test/test.dart';
+
+import 'mocks/mock_client_report_recorder.dart';
+import 'mocks/mock_sentry_client.dart';
+import 'test_utils.dart';
+
+void main() {
+  group('SimpleSpan', () {
+    late Fixture fixture;
+
+    setUp(() {
+      fixture = Fixture();
+    });
+
+    test('end finishes the span', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      // Should not throw
+      span.end();
+      // TODO: verify span is finished once SimpleSpan implements it
+    });
+
+    test('end with custom timestamp sets end time', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+      final endTime = DateTime.now().add(Duration(seconds: 5));
+
+      span.end(endTimestamp: endTime);
+      // TODO: verify end timestamp once SimpleSpan implements it
+    });
+
+    test('setAttribute sets single attribute', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      span.setAttribute('key', SentryAttribute.string('value'));
+      // TODO: verify attribute once SimpleSpan implements it
+    });
+
+    test('setAttributes sets multiple attributes', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      span.setAttributes({
+        'key1': SentryAttribute.string('value1'),
+        'key2': SentryAttribute.int(42),
+      });
+      // TODO: verify attributes once SimpleSpan implements it
+    });
+
+    test('setName sets span name', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'initial-name', parentSpan: null, hub: hub);
+
+      span.setName('updated-name');
+      // TODO: verify name once SimpleSpan implements it
+    });
+
+    test('setStatus sets span status to ok', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      span.setStatus(SpanV2Status.ok);
+      // TODO: verify status once SimpleSpan implements it
+    });
+
+    test('setStatus sets span status to error', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      span.setStatus(SpanV2Status.error);
+      // TODO: verify status once SimpleSpan implements it
+    });
+
+    test('parentSpan returns the parent span', () {
+      final hub = fixture.getSut();
+      final parent = SimpleSpan(name: 'parent', parentSpan: null, hub: hub);
+      final child = SimpleSpan(name: 'child', parentSpan: parent, hub: hub);
+
+      expect(child.parentSpan, equals(parent));
+    });
+
+    test('parentSpan returns null for root span', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'root', parentSpan: null, hub: hub);
+
+      expect(span.parentSpan, isNull);
+    });
+
+    test('name returns the span name', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'my-span-name', parentSpan: null, hub: hub);
+
+      expect(span.name, equals('my-span-name'));
+    });
+  });
+
+  group('NoOpSpan', () {
+    test('NoOpSpan operations do not throw', () {
+      const span = NoOpSpan();
+
+      // All operations should be no-ops and not throw
+      span.end();
+      span.end(endTimestamp: DateTime.now());
+      span.setAttribute('key', SentryAttribute.string('value'));
+      span.setAttributes({'key': SentryAttribute.string('value')});
+      span.setName('name');
+      span.setStatus(SpanV2Status.ok);
+      span.setStatus(SpanV2Status.error);
+      expect(span.toJson(), isEmpty);
+    });
+  });
+}
+
+class Fixture {
+  final client = MockSentryClient();
+  final recorder = MockClientReportRecorder();
+
+  final options = defaultTestOptions();
+
+  Hub getSut({
+    double? tracesSampleRate = 1.0,
+  }) {
+    options.tracesSampleRate = tracesSampleRate;
+
+    final hub = Hub(options);
+
+    hub.bindClient(client);
+    options.recorder = recorder;
+
+    return hub;
+  }
+}
+

From 8713bfc03f5cf1e63fd4c6e250cae5919d730ebc Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:29:29 +0100
Subject: [PATCH 04/16] Update

---
 packages/dart/lib/src/protocol/noop_span.dart |  19 +-
 .../dart/lib/src/protocol/simple_span.dart    |  45 ++--
 packages/dart/lib/src/protocol/span.dart      |  31 ++-
 .../dart/lib/src/protocol/unset_span.dart     |  19 +-
 packages/dart/test/hub_span_test.dart         | 204 ++++++++----------
 packages/dart/test/span_test.dart             |  55 +++--
 6 files changed, 208 insertions(+), 165 deletions(-)

diff --git a/packages/dart/lib/src/protocol/noop_span.dart b/packages/dart/lib/src/protocol/noop_span.dart
index ef55a4410c..bd673bcd96 100644
--- a/packages/dart/lib/src/protocol/noop_span.dart
+++ b/packages/dart/lib/src/protocol/noop_span.dart
@@ -4,14 +4,17 @@ class NoOpSpan implements Span {
   const NoOpSpan();
 
   @override
-  String get name => '';
+  final String name = 'NoOpSpan';
 
   @override
-  Span? get parentSpan => null;
+  final SpanV2Status status = SpanV2Status.ok;
 
   @override
   void end({DateTime? endTimestamp}) {}
 
+  @override
+  Span? get parentSpan => NoOpSpan();
+
   @override
   void setAttribute(String key, SentryAttribute value) {}
 
@@ -19,11 +22,17 @@ class NoOpSpan implements Span {
   void setAttributes(Map<String, SentryAttribute> attributes) {}
 
   @override
-  void setName(String name) {}
+  Map<String, dynamic> toJson() => {};
 
   @override
-  void setStatus(SpanV2Status status) {}
+  set name(String name) {}
 
   @override
-  Map<String, dynamic> toJson() => {};
+  set status(SpanV2Status status) {}
+
+  @override
+  Map<String, SentryAttribute> get attributes => {};
+
+  @override
+  DateTime? get endTimestamp => null;
 }
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index c43555fe29..dbaae046ab 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -2,39 +2,58 @@ import '../../sentry.dart';
 
 class SimpleSpan implements Span {
   final Hub hub;
+  final Map<String, SentryAttribute> _attributes = {};
 
   @override
   final Span? parentSpan;
 
+  String _name;
+  SpanV2Status _status = SpanV2Status.ok;
+  DateTime? _endTimestamp;
+
+  SimpleSpan({
+    required String name,
+    this.parentSpan,
+    Hub? hub,
+  })  : hub = hub ?? HubAdapter(),
+        _name = name;
+
   @override
-  final String name;
+  DateTime? get endTimestamp => _endTimestamp;
 
-  SimpleSpan({required this.name, required this.parentSpan, Hub? hub})
-      : hub = hub ?? HubAdapter();
+  @override
+  Map<String, SentryAttribute> get attributes => Map.unmodifiable(_attributes);
 
   @override
-  void end({DateTime? endTimestamp}) {
-    // TODO: implement end
+  String get name => _name;
+
+  @override
+  set name(String value) {
+    _name = value;
   }
 
   @override
-  void setAttribute(String key, SentryAttribute value) {
-    // TODO: implement setAttribute
+  SpanV2Status get status => _status;
+
+  @override
+  set status(SpanV2Status value) {
+    _status = value;
   }
 
   @override
-  void setAttributes(Map<String, SentryAttribute> attributes) {
-    // TODO: implement setAttributes
+  void end({DateTime? endTimestamp}) {
+    _endTimestamp = endTimestamp ?? DateTime.now().toUtc();
+    // TODO: add this span to buffer through hub.captureSpan
   }
 
   @override
-  void setName(String name) {
-    // TODO: implement setName
+  void setAttribute(String key, SentryAttribute value) {
+    _attributes[key] = value;
   }
 
   @override
-  void setStatus(SpanV2Status status) {
-    // TODO: implement setStatus
+  void setAttributes(Map<String, SentryAttribute> attributes) {
+    _attributes.addAll(attributes);
   }
 
   @override
diff --git a/packages/dart/lib/src/protocol/span.dart b/packages/dart/lib/src/protocol/span.dart
index d800b12b16..15509c67fb 100644
--- a/packages/dart/lib/src/protocol/span.dart
+++ b/packages/dart/lib/src/protocol/span.dart
@@ -1,8 +1,12 @@
+import 'dart:collection';
+
 import 'package:meta/meta.dart';
 
 import '../../sentry.dart';
 
-/// Represents the Span model based on https://develop.sentry.dev/sdk/telemetry/spans/span-api/
+// Span specs: https://develop.sentry.dev/sdk/telemetry/spans/span-api/
+
+/// Represents a basic telemetry span.
 abstract class Span {
   @internal
   const Span();
@@ -10,14 +14,31 @@ abstract class Span {
   /// Gets the name of the span.
   String get name;
 
+  /// Sets the name of the span.
+  set name(String name);
+
   /// Gets the parentSpan.
   /// If null this span has no parent.
   Span? get parentSpan;
 
+  /// Gets the status of the span.
+  SpanV2Status get status;
+
+  /// Sets the status of the span.
+  set status(SpanV2Status status);
+
+  /// Gets the end timestamp of the span.
+  DateTime? get endTimestamp;
+
+  /// Gets a read-only view of the attributes of the span.
+  ///
+  /// The returned map must not be mutated by callers.
+  Map<String, SentryAttribute> get attributes;
+
   /// Ends the span.
   ///
   /// [endTimestamp] can be used to override the end time.
-  /// If omitted, the span ends using the current time.
+  /// If omitted, the span ends using the current time when end is executed.
   void end({DateTime? endTimestamp});
 
   /// Sets a single attribute.
@@ -30,12 +51,6 @@ abstract class Span {
   /// Overrides if the attributes already exist.
   void setAttributes(Map<String, SentryAttribute> attributes);
 
-  /// Sets the status of the span.
-  void setStatus(SpanV2Status status);
-
-  /// Sets the name of the span.
-  void setName(String name);
-
   @internal
   Map<String, dynamic> toJson();
 }
diff --git a/packages/dart/lib/src/protocol/unset_span.dart b/packages/dart/lib/src/protocol/unset_span.dart
index 164c868ed4..6411bcae9f 100644
--- a/packages/dart/lib/src/protocol/unset_span.dart
+++ b/packages/dart/lib/src/protocol/unset_span.dart
@@ -32,17 +32,26 @@ class UnsetSpan extends Span {
   }
 
   @override
-  void setName(String name) {
+  Map<String, dynamic> toJson() {
     throw UnimplementedError('$UnsetSpan methods should not be used');
   }
 
   @override
-  void setStatus(SpanV2Status status) {
-    throw UnimplementedError('$UnsetSpan methods should not be used');
+  set name(String name) {
+    throw UnimplementedError();
   }
 
   @override
-  Map<String, dynamic> toJson() {
-    throw UnimplementedError('$UnsetSpan methods should not be used');
+  set status(SpanV2Status status) {
+    throw UnimplementedError();
   }
+
+  @override
+  SpanV2Status get status => throw UnimplementedError();
+
+  @override
+  Map<String, SentryAttribute> get attributes => throw UnimplementedError();
+
+  @override
+  DateTime? get endTimestamp => throw UnimplementedError();
 }
diff --git a/packages/dart/test/hub_span_test.dart b/packages/dart/test/hub_span_test.dart
index 2f487393b0..b1e110d60d 100644
--- a/packages/dart/test/hub_span_test.dart
+++ b/packages/dart/test/hub_span_test.dart
@@ -8,145 +8,144 @@ import 'mocks/mock_sentry_client.dart';
 import 'test_utils.dart';
 
 void main() {
-  group('Hub startSpan', () {
+  group('Hub', () {
     late Fixture fixture;
 
     setUp(() {
       fixture = Fixture();
     });
 
-    test('startSpan returns SimpleSpan when tracing is enabled', () {
-      final hub = fixture.getSut();
+    group('startSpan', () {
+      group('span creation', () {
+        test('returns SimpleSpan when tracing is enabled', () {
+          final hub = fixture.getSut();
 
-      final span = hub.startSpan('test-span');
+          final span = hub.startSpan('test-span');
 
-      expect(span, isA<SimpleSpan>());
-    });
+          expect(span, isA<SimpleSpan>());
+        });
 
-    test('startSpan returns NoOpSpan when tracing is disabled', () {
-      final hub = fixture.getSut(tracesSampleRate: null);
+        test('returns NoOpSpan when tracing is disabled', () {
+          final hub = fixture.getSut(tracesSampleRate: null);
 
-      final span = hub.startSpan('test-span');
+          final span = hub.startSpan('test-span');
 
-      expect(span, isA<NoOpSpan>());
-    });
+          expect(span, isA<NoOpSpan>());
+        });
 
-    test('startSpan returns NoOpSpan when hub is disabled', () async {
-      final hub = fixture.getSut();
-      await hub.close();
+        test('returns NoOpSpan when hub is closed', () async {
+          final hub = fixture.getSut();
+          await hub.close();
 
-      final span = hub.startSpan('test-span');
+          final span = hub.startSpan('test-span');
 
-      expect(span, isA<NoOpSpan>());
-    });
+          expect(span, isA<NoOpSpan>());
+        });
 
-    test('startSpan sets span name', () {
-      final hub = fixture.getSut();
+        test('sets span name from parameter', () {
+          final hub = fixture.getSut();
 
-      final span = hub.startSpan('my-span-name');
-
-      expect(span, isA<SimpleSpan>());
-      // TODO: verify span name once SimpleSpan implements it
-    });
+          final span = hub.startSpan('my-span-name');
 
-    test('startSpan with active=true sets span as active on scope', () {
-      final hub = fixture.getSut();
+          expect(span.name, equals('my-span-name'));
+        });
 
-      final span = hub.startSpan('test-span', active: true);
+        test('sets attributes on span when provided', () {
+          final hub = fixture.getSut();
+          final attributes = {
+            'attr1': SentryAttribute.string('value1'),
+            'attr2': SentryAttribute.int(42),
+          };
 
-      expect(hub.scope.getActiveSpan(), equals(span));
-    });
+          final span = hub.startSpan('test-span', attributes: attributes);
 
-    test('startSpan with active=false does not set span as active on scope',
-        () {
-      final hub = fixture.getSut();
+          expect(span.attributes, equals(attributes));
+        });
+      });
 
-      hub.startSpan('test-span', active: false);
+      group('active span handling', () {
+        test('sets span as active on scope when active is true', () {
+          final hub = fixture.getSut();
 
-      expect(hub.scope.getActiveSpan(), isNull);
-    });
+          final span = hub.startSpan('test-span', active: true);
 
-    test('startSpan uses active span as parent when parentSpan is not provided',
-        () {
-      final hub = fixture.getSut();
+          expect(hub.scope.getActiveSpan(), equals(span));
+        });
 
-      // Start first span which becomes active
-      final parentSpan = hub.startSpan('parent-span');
-      expect(hub.scope.getActiveSpan(), equals(parentSpan));
+        test('does not set span as active on scope when active is false', () {
+          final hub = fixture.getSut();
 
-      // Start second span - should use active span as parent
-      final childSpan = hub.startSpan('child-span');
-      expect(childSpan, isA<SimpleSpan>());
-      expect(childSpan.parentSpan, equals(parentSpan));
-    });
+          hub.startSpan('test-span', active: false);
 
-    test('startSpan with explicit parentSpan uses that as parent', () {
-      final hub = fixture.getSut();
+          expect(hub.scope.getActiveSpan(), isNull);
+        });
+      });
 
-      final explicitParent = hub.startSpan('explicit-parent');
-      // Start another span to change active span
-      hub.startSpan('other-span');
+      group('parent span resolution', () {
+        test('creates root span when no active span exists', () {
+          final hub = fixture.getSut();
 
-      // Start span with explicit parent
-      final childSpan = hub.startSpan('child-span',
-          parentSpan: explicitParent, active: false);
+          final span = hub.startSpan('test-span');
 
-      expect(childSpan, isA<SimpleSpan>());
-      expect(childSpan.parentSpan, equals(explicitParent));
-    });
+          expect(span.parentSpan, isNull);
+        });
 
-    test('startSpan with parentSpan=null creates root/segment span', () {
-      final hub = fixture.getSut();
+        test('uses active span as parent when parentSpan is not provided', () {
+          final hub = fixture.getSut();
+          final parentSpan = hub.startSpan('parent-span');
 
-      // Start active span first
-      hub.startSpan('active-span');
+          final childSpan = hub.startSpan('child-span');
 
-      // Start span with null parent - should be root span
-      final rootSpan = hub.startSpan('root-span', parentSpan: null);
+          expect(childSpan.parentSpan, equals(parentSpan));
+        });
 
-      expect(rootSpan, isA<SimpleSpan>());
-      expect(rootSpan.parentSpan, isNull);
-    });
+        test('uses explicit parentSpan instead of active span when provided',
+            () {
+          final hub = fixture.getSut();
+          final explicitParent = hub.startSpan('explicit-parent');
+          hub.startSpan('other-span'); // Changes active span
 
-    test('startSpan with attributes sets attributes on span', () {
-      final hub = fixture.getSut();
-      final attributes = {
-        'attr1': SentryAttribute.string('value1'),
-        'attr2': SentryAttribute.int(42),
-      };
+          final childSpan = hub.startSpan(
+            'child-span',
+            parentSpan: explicitParent,
+            active: false,
+          );
 
-      final span = hub.startSpan('test-span', attributes: attributes);
+          expect(childSpan.parentSpan, equals(explicitParent));
+        });
 
-      expect(span, isA<SimpleSpan>());
-      // TODO: verify attributes once SimpleSpan implements it
-    });
-  });
+        test('creates root span when parentSpan is explicitly set to null', () {
+          final hub = fixture.getSut();
+          hub.startSpan('active-span');
 
-  group('Hub captureSpan', () {
-    late Fixture fixture;
+          final rootSpan = hub.startSpan('root-span', parentSpan: null);
 
-    setUp(() {
-      fixture = Fixture();
+          expect(rootSpan.parentSpan, isNull);
+        });
+      });
     });
 
-    test('captureSpan removes span from active spans', () {
-      final hub = fixture.getSut();
+    group('captureSpan', () {
+      // TODO: add test that it was added to buffer
 
-      final span = hub.startSpan('test-span');
-      expect(hub.scope.activeSpans, contains(span));
+      test('removes span from active spans on scope', () {
+        final hub = fixture.getSut();
+        final span = hub.startSpan('test-span');
+        expect(hub.scope.activeSpans, contains(span));
 
-      hub.captureSpan(span);
+        hub.captureSpan(span);
 
-      expect(hub.scope.activeSpans, isNot(contains(span)));
-    });
+        expect(hub.scope.activeSpans, isNot(contains(span)));
+      });
 
-    test('captureSpan does nothing when hub is disabled', () async {
-      final hub = fixture.getSut();
-      final span = hub.startSpan('test-span');
-      await hub.close();
+      test('does nothing when hub is closed', () async {
+        final hub = fixture.getSut();
+        final span = hub.startSpan('test-span');
+        await hub.close();
 
-      // Should not throw
-      hub.captureSpan(span);
+        // Should not throw
+        hub.captureSpan(span);
+      });
     });
   });
 }
@@ -157,10 +156,6 @@ class Fixture {
 
   final options = defaultTestOptions();
 
-  SentryLevel? loggedLevel;
-  String? loggedMessage;
-  Object? loggedException;
-
   Hub getSut({
     double? tracesSampleRate = 1.0,
     TracesSamplerCallback? tracesSampler,
@@ -169,7 +164,6 @@ class Fixture {
     options.tracesSampleRate = tracesSampleRate;
     options.tracesSampler = tracesSampler;
     options.debug = debug;
-    options.log = mockLogger;
 
     final hub = Hub(options);
 
@@ -178,16 +172,4 @@ class Fixture {
 
     return hub;
   }
-
-  void mockLogger(
-    SentryLevel level,
-    String message, {
-    String? logger,
-    Object? exception,
-    StackTrace? stackTrace,
-  }) {
-    loggedLevel = level;
-    loggedMessage = message;
-    loggedException = exception;
-  }
 }
diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index 8222977ab0..54fb3a15df 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -19,61 +19,71 @@ void main() {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
-      // Should not throw
       span.end();
       // TODO: verify span is finished once SimpleSpan implements it
     });
 
+    test('end sets current time by default', () {
+      final hub = fixture.getSut();
+      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+
+      span.end();
+
+      final now = DateTime.now();
+      expect(span.endTimestamp?.microsecondsSinceEpoch,
+          lessThan(now.microsecondsSinceEpoch));
+    });
+
     test('end with custom timestamp sets end time', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
       final endTime = DateTime.now().add(Duration(seconds: 5));
 
       span.end(endTimestamp: endTime);
-      // TODO: verify end timestamp once SimpleSpan implements it
+
+      expect(span.endTimestamp, equals(endTime));
     });
 
     test('setAttribute sets single attribute', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
-      span.setAttribute('key', SentryAttribute.string('value'));
-      // TODO: verify attribute once SimpleSpan implements it
+      final attributeValue = SentryAttribute.string('value');
+      span.setAttribute('key', attributeValue);
+
+      expect(span.attributes, equals({'key': attributeValue}));
     });
 
     test('setAttributes sets multiple attributes', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
-      span.setAttributes({
+      final attributes = {
         'key1': SentryAttribute.string('value1'),
         'key2': SentryAttribute.int(42),
-      });
-      // TODO: verify attributes once SimpleSpan implements it
+      };
+      span.setAttributes(attributes);
+
+      expect(span.attributes, equals(attributes));
     });
 
     test('setName sets span name', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'initial-name', parentSpan: null, hub: hub);
 
-      span.setName('updated-name');
-      // TODO: verify name once SimpleSpan implements it
+      span.name = 'updated-name';
+      expect(span.status, equals('updated-name'));
     });
 
-    test('setStatus sets span status to ok', () {
+    test('can set span status', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
-      span.setStatus(SpanV2Status.ok);
-      // TODO: verify status once SimpleSpan implements it
-    });
-
-    test('setStatus sets span status to error', () {
-      final hub = fixture.getSut();
-      final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
+      span.status = SpanV2Status.ok;
+      expect(span.status, equals(SpanV2Status.ok));
 
-      span.setStatus(SpanV2Status.error);
-      // TODO: verify status once SimpleSpan implements it
+      span.status = SpanV2Status.error;
+      expect(span.status, equals(SpanV2Status.error));
     });
 
     test('parentSpan returns the parent span', () {
@@ -108,9 +118,9 @@ void main() {
       span.end(endTimestamp: DateTime.now());
       span.setAttribute('key', SentryAttribute.string('value'));
       span.setAttributes({'key': SentryAttribute.string('value')});
-      span.setName('name');
-      span.setStatus(SpanV2Status.ok);
-      span.setStatus(SpanV2Status.error);
+      span.name = 'name';
+      span.status = SpanV2Status.ok;
+      span.status = SpanV2Status.error;
       expect(span.toJson(), isEmpty);
     });
   });
@@ -135,4 +145,3 @@ class Fixture {
     return hub;
   }
 }
-

From 1adb9a3600bd76948dac4e5c29948c26d15979ae Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:30:26 +0100
Subject: [PATCH 05/16] Update

---
 packages/dart/test/span_test.dart | 9 +--------
 1 file changed, 1 insertion(+), 8 deletions(-)

diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index 54fb3a15df..84739595d5 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -3,7 +3,6 @@ import 'package:sentry/src/protocol/noop_span.dart';
 import 'package:sentry/src/protocol/simple_span.dart';
 import 'package:test/test.dart';
 
-import 'mocks/mock_client_report_recorder.dart';
 import 'mocks/mock_sentry_client.dart';
 import 'test_utils.dart';
 
@@ -128,7 +127,6 @@ void main() {
 
 class Fixture {
   final client = MockSentryClient();
-  final recorder = MockClientReportRecorder();
 
   final options = defaultTestOptions();
 
@@ -136,12 +134,7 @@ class Fixture {
     double? tracesSampleRate = 1.0,
   }) {
     options.tracesSampleRate = tracesSampleRate;
-
-    final hub = Hub(options);
-
-    hub.bindClient(client);
-    options.recorder = recorder;
-
+    final hub = Hub(options)..bindClient(client);
     return hub;
   }
 }

From 5e74caa35898a968f0b378eaaaab457e62e78938 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:32:27 +0100
Subject: [PATCH 06/16] Remove unnecessary import

---
 packages/dart/lib/src/protocol/span.dart | 2 --
 1 file changed, 2 deletions(-)

diff --git a/packages/dart/lib/src/protocol/span.dart b/packages/dart/lib/src/protocol/span.dart
index 15509c67fb..0d73355517 100644
--- a/packages/dart/lib/src/protocol/span.dart
+++ b/packages/dart/lib/src/protocol/span.dart
@@ -1,5 +1,3 @@
-import 'dart:collection';
-
 import 'package:meta/meta.dart';
 
 import '../../sentry.dart';

From b1a38325b971007ef042ddaff980b5b3763dc372 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:32:59 +0100
Subject: [PATCH 07/16] Remove unnecessary import

---
 packages/dart/lib/src/protocol/span.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dart/lib/src/protocol/span.dart b/packages/dart/lib/src/protocol/span.dart
index 0d73355517..b014cc9296 100644
--- a/packages/dart/lib/src/protocol/span.dart
+++ b/packages/dart/lib/src/protocol/span.dart
@@ -15,7 +15,7 @@ abstract class Span {
   /// Sets the name of the span.
   set name(String name);
 
-  /// Gets the parentSpan.
+  /// Gets the parent span.
   /// If null this span has no parent.
   Span? get parentSpan;
 

From c7cbeeae2884b416062cf86aaa7d874beeb9658f Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:34:09 +0100
Subject: [PATCH 08/16] Update

---
 packages/dart/lib/src/scope.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index c6679e4d6d..c522293140 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -55,7 +55,7 @@ class Scope {
   /// becomes a child of this active span.
   @internal
   Span? getActiveSpan() {
-    return _activeSpans.isNotEmpty ? _activeSpans.last : null;
+    return _activeSpans.lastOrNull;
   }
 
   /// Sets the given [span] as the currently active span.

From 144405e4aff0e5d583c394abf155352fbdc52b86 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:34:54 +0100
Subject: [PATCH 09/16] Update

---
 packages/dart/lib/src/scope.dart | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index c522293140..f1e16892e5 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -63,9 +63,6 @@ class Scope {
   /// Active spans are used to automatically parent new spans.
   /// When a new span is started with `active: true` (the default), it becomes
   /// a child of the currently active span.
-  ///
-  /// The active spans are maintained as a stack - the most recently set span
-  /// is the current active span.
   @internal
   void setActiveSpan(Span span) {
     _activeSpans.add(span);

From ab66ec99a65b2b74aed3b6ba234f830eaf7aa886 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:40:37 +0100
Subject: [PATCH 10/16] Update

---
 packages/dart/test/span_test.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index 84739595d5..e6dfe44208 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -71,7 +71,7 @@ void main() {
       final span = SimpleSpan(name: 'initial-name', parentSpan: null, hub: hub);
 
       span.name = 'updated-name';
-      expect(span.status, equals('updated-name'));
+      expect(span.name, equals('updated-name'));
     });
 
     test('can set span status', () {

From 7d685bef4cab42e8ce750c714340759503f6f334 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 22:41:32 +0100
Subject: [PATCH 11/16] Update

---
 packages/dart/lib/src/scope.dart | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index f1e16892e5..f8e1d41229 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -71,7 +71,7 @@ class Scope {
   /// Removes the given [span] from the active spans list.
   ///
   /// This should be called when a span ends to remove it from the active
-  /// span hierarchy.
+  /// span list.
   @internal
   void removeActiveSpan(Span span) {
     _activeSpans.remove(span);

From 33d88922390a36a108f9109df694f2d0173deefa Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 23:34:07 +0100
Subject: [PATCH 12/16] Update

---
 packages/dart/lib/src/hub.dart                  |  2 +-
 packages/dart/lib/src/protocol/noop_span.dart   |  2 +-
 packages/dart/lib/src/protocol/simple_span.dart |  4 +++-
 packages/dart/test/hub_span_test.dart           |  4 ++++
 packages/dart/test/span_test.dart               | 11 +++++++++++
 5 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/packages/dart/lib/src/hub.dart b/packages/dart/lib/src/hub.dart
index f8bfbc14f2..d12cff1ca8 100644
--- a/packages/dart/lib/src/hub.dart
+++ b/packages/dart/lib/src/hub.dart
@@ -631,7 +631,7 @@ class Hub {
 
     scope.removeActiveSpan(span);
 
-    // TODO: implement span buffer and add the span to the buffer
+    // TODO: run this span through span specific pipeline and then forward to span buffer
   }
 
   @internal
diff --git a/packages/dart/lib/src/protocol/noop_span.dart b/packages/dart/lib/src/protocol/noop_span.dart
index bd673bcd96..326c8d36be 100644
--- a/packages/dart/lib/src/protocol/noop_span.dart
+++ b/packages/dart/lib/src/protocol/noop_span.dart
@@ -13,7 +13,7 @@ class NoOpSpan implements Span {
   void end({DateTime? endTimestamp}) {}
 
   @override
-  Span? get parentSpan => NoOpSpan();
+  Span? get parentSpan => null;
 
   @override
   void setAttribute(String key, SentryAttribute value) {}
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index dbaae046ab..84d9d61976 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -1,3 +1,5 @@
+import 'package:meta/meta.dart';
+
 import '../../sentry.dart';
 
 class SimpleSpan implements Span {
@@ -43,7 +45,7 @@ class SimpleSpan implements Span {
   @override
   void end({DateTime? endTimestamp}) {
     _endTimestamp = endTimestamp ?? DateTime.now().toUtc();
-    // TODO: add this span to buffer through hub.captureSpan
+    hub.captureSpan(this);
   }
 
   @override
diff --git a/packages/dart/test/hub_span_test.dart b/packages/dart/test/hub_span_test.dart
index b1e110d60d..0126fe993f 100644
--- a/packages/dart/test/hub_span_test.dart
+++ b/packages/dart/test/hub_span_test.dart
@@ -122,6 +122,10 @@ void main() {
 
           expect(rootSpan.parentSpan, isNull);
         });
+
+        test('should not allow finished span to be use as parent', () {
+          // TODO: this test case needs more clarification
+        });
       });
     });
 
diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index e6dfe44208..484595341a 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -43,6 +43,17 @@ void main() {
       expect(span.endTimestamp, equals(endTime));
     });
 
+    test('end removes active span from scope', () {
+      final hub = fixture.getSut();
+      final span = hub.startSpan('test-span');
+      expect(hub.scope.activeSpans.length, 1);
+      expect(hub.scope.activeSpans.first, equals(span));
+
+      span.end();
+
+      expect(hub.scope.activeSpans, isEmpty);
+    });
+
     test('setAttribute sets single attribute', () {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);

From d74fe5a38d071ff799143f30d6a33478ee6d3925 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 23:39:42 +0100
Subject: [PATCH 13/16] Update

---
 packages/dart/lib/src/protocol/noop_span.dart   | 3 +++
 packages/dart/lib/src/protocol/simple_span.dart | 7 +++++--
 packages/dart/lib/src/protocol/span.dart        | 3 +++
 packages/dart/lib/src/protocol/unset_span.dart  | 3 +++
 packages/dart/lib/src/scope.dart                | 7 +++++++
 packages/dart/test/scope_test.dart              | 1 +
 packages/dart/test/span_test.dart               | 4 +++-
 7 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/packages/dart/lib/src/protocol/noop_span.dart b/packages/dart/lib/src/protocol/noop_span.dart
index 326c8d36be..c0980fe4e8 100644
--- a/packages/dart/lib/src/protocol/noop_span.dart
+++ b/packages/dart/lib/src/protocol/noop_span.dart
@@ -35,4 +35,7 @@ class NoOpSpan implements Span {
 
   @override
   DateTime? get endTimestamp => null;
+
+  @override
+  bool get isFinished => false;
 }
diff --git a/packages/dart/lib/src/protocol/simple_span.dart b/packages/dart/lib/src/protocol/simple_span.dart
index 84d9d61976..1e00257975 100644
--- a/packages/dart/lib/src/protocol/simple_span.dart
+++ b/packages/dart/lib/src/protocol/simple_span.dart
@@ -1,5 +1,3 @@
-import 'package:meta/meta.dart';
-
 import '../../sentry.dart';
 
 class SimpleSpan implements Span {
@@ -12,6 +10,7 @@ class SimpleSpan implements Span {
   String _name;
   SpanV2Status _status = SpanV2Status.ok;
   DateTime? _endTimestamp;
+  bool _isFinished = false;
 
   SimpleSpan({
     required String name,
@@ -46,6 +45,7 @@ class SimpleSpan implements Span {
   void end({DateTime? endTimestamp}) {
     _endTimestamp = endTimestamp ?? DateTime.now().toUtc();
     hub.captureSpan(this);
+    _isFinished = true;
   }
 
   @override
@@ -58,6 +58,9 @@ class SimpleSpan implements Span {
     _attributes.addAll(attributes);
   }
 
+  @override
+  bool get isFinished => _isFinished;
+
   @override
   Map<String, dynamic> toJson() {
     // TODO: implement toJson
diff --git a/packages/dart/lib/src/protocol/span.dart b/packages/dart/lib/src/protocol/span.dart
index b014cc9296..28efff7ef9 100644
--- a/packages/dart/lib/src/protocol/span.dart
+++ b/packages/dart/lib/src/protocol/span.dart
@@ -49,6 +49,9 @@ abstract class Span {
   /// Overrides if the attributes already exist.
   void setAttributes(Map<String, SentryAttribute> attributes);
 
+  @internal
+  bool get isFinished;
+
   @internal
   Map<String, dynamic> toJson();
 }
diff --git a/packages/dart/lib/src/protocol/unset_span.dart b/packages/dart/lib/src/protocol/unset_span.dart
index 6411bcae9f..ed7303e6c0 100644
--- a/packages/dart/lib/src/protocol/unset_span.dart
+++ b/packages/dart/lib/src/protocol/unset_span.dart
@@ -54,4 +54,7 @@ class UnsetSpan extends Span {
 
   @override
   DateTime? get endTimestamp => throw UnimplementedError();
+
+  @override
+  bool get isFinished => throw UnimplementedError();
 }
diff --git a/packages/dart/lib/src/scope.dart b/packages/dart/lib/src/scope.dart
index f8e1d41229..f1382d9ede 100644
--- a/packages/dart/lib/src/scope.dart
+++ b/packages/dart/lib/src/scope.dart
@@ -43,6 +43,8 @@ class Scope {
   /// Returns active transaction or null if there is no active transaction.
   ISentrySpan? span;
 
+  /// List of active spans.
+  /// The last span in the list is the current active span.
   final List<Span> _activeSpans = [];
 
   @visibleForTesting
@@ -307,6 +309,7 @@ class Scope {
     _replayId = null;
     propagationContext = PropagationContext();
     _attributes.clear();
+    _activeSpans.clear();
 
     _clearBreadcrumbsSync();
     _setUserSync(null);
@@ -514,6 +517,10 @@ class Scope {
       clone.setAttributes(Map.from(_attributes));
     }
 
+    if (_activeSpans.isNotEmpty) {
+      clone._activeSpans.addAll(_activeSpans);
+    }
+
     return clone;
   }
 
diff --git a/packages/dart/test/scope_test.dart b/packages/dart/test/scope_test.dart
index 98b7892d19..a57bde0f84 100644
--- a/packages/dart/test/scope_test.dart
+++ b/packages/dart/test/scope_test.dart
@@ -431,6 +431,7 @@ void main() {
     expect(sut.eventProcessors.length, 0);
     expect(sut.replayId, isNull);
     expect(sut.attributes, isEmpty);
+    expect(sut.activeSpans, isEmpty);
   });
 
   test('clones', () async {
diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index 484595341a..64fed76482 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -19,7 +19,9 @@ void main() {
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
       span.end();
-      // TODO: verify span is finished once SimpleSpan implements it
+
+      expect(span.endTimestamp, isNotNull);
+      expect(span.isFinished, isTrue);
     });
 
     test('end sets current time by default', () {

From 2b9c8b26e826beb64e9dfb08aee23fa6b799fb00 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 23:48:33 +0100
Subject: [PATCH 14/16] Update

---
 packages/dart/test/span_test.dart | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/packages/dart/test/span_test.dart b/packages/dart/test/span_test.dart
index 64fed76482..073bd00229 100644
--- a/packages/dart/test/span_test.dart
+++ b/packages/dart/test/span_test.dart
@@ -28,11 +28,17 @@ void main() {
       final hub = fixture.getSut();
       final span = SimpleSpan(name: 'test-span', parentSpan: null, hub: hub);
 
+      final before = DateTime.now().toUtc();
       span.end();
+      final after = DateTime.now().toUtc();
 
-      final now = DateTime.now();
-      expect(span.endTimestamp?.microsecondsSinceEpoch,
-          lessThan(now.microsecondsSinceEpoch));
+      expect(span.endTimestamp, isNotNull);
+      expect(span.endTimestamp!.isAfter(before) || span.endTimestamp == before,
+          isTrue,
+          reason: 'endTimestamp should be >= time before end() was called');
+      expect(span.endTimestamp!.isBefore(after) || span.endTimestamp == after,
+          isTrue,
+          reason: 'endTimestamp should be <= time after end() was called');
     });
 
     test('end with custom timestamp sets end time', () {

From c5a24b443bbae42f6e36a46169e0a13fead70879 Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Tue, 2 Dec 2025 23:54:45 +0100
Subject: [PATCH 15/16] Update

---
 packages/dart/lib/src/hub.dart        |  3 -
 packages/dart/test/hub_span_test.dart | 87 +++++++++++++++++++++++++++
 2 files changed, 87 insertions(+), 3 deletions(-)

diff --git a/packages/dart/lib/src/hub.dart b/packages/dart/lib/src/hub.dart
index d12cff1ca8..b8a6eecd67 100644
--- a/packages/dart/lib/src/hub.dart
+++ b/packages/dart/lib/src/hub.dart
@@ -598,13 +598,10 @@ class Hub {
     // - If parentSpan is UnsetSpan (default), use the currently active span
     // - If parentSpan is a specific Span, use that as the parent
     // - If parentSpan is null, create a root/segment span (no parent)
-    // ignore: unused_local_variable
     final Span? resolvedParentSpan;
     if (parentSpan is UnsetSpan) {
-      // Use the currently active span from scope as parent
       resolvedParentSpan = scope.getActiveSpan();
     } else {
-      // Use the explicitly provided parent (can be null for root/segment span)
       resolvedParentSpan = parentSpan;
     }
 
diff --git a/packages/dart/test/hub_span_test.dart b/packages/dart/test/hub_span_test.dart
index 0126fe993f..d9c3e3eba4 100644
--- a/packages/dart/test/hub_span_test.dart
+++ b/packages/dart/test/hub_span_test.dart
@@ -127,6 +127,93 @@ void main() {
           // TODO: this test case needs more clarification
         });
       });
+
+      group('span hierarchy', () {
+        test('builds 3-level hierarchy with automatic parenting', () {
+          final hub = fixture.getSut();
+
+          final grandparent = hub.startSpan('grandparent');
+          final parent = hub.startSpan('parent');
+          final child = hub.startSpan('child');
+
+          expect(grandparent.parentSpan, isNull);
+          expect(parent.parentSpan, equals(grandparent));
+          expect(child.parentSpan, equals(parent));
+        });
+
+        test('ending middle span allows new span to parent to grandparent', () {
+          final hub = fixture.getSut();
+
+          final grandparent = hub.startSpan('grandparent');
+          final parent = hub.startSpan('parent');
+          parent.end();
+
+          final sibling = hub.startSpan('sibling');
+
+          expect(sibling.parentSpan, equals(grandparent));
+        });
+
+        test('sibling spans share same parent when created as inactive', () {
+          final hub = fixture.getSut();
+
+          final parent = hub.startSpan('parent');
+          final child1 = hub.startSpan('child1', active: false);
+          final child2 = hub.startSpan('child2', active: false);
+
+          expect(child1.parentSpan, equals(parent));
+          expect(child2.parentSpan, equals(parent));
+        });
+
+        test('ending spans in reverse order cleans up active spans correctly',
+            () {
+          final hub = fixture.getSut();
+
+          final span1 = hub.startSpan('span1');
+          final span2 = hub.startSpan('span2');
+          final span3 = hub.startSpan('span3');
+
+          expect(hub.scope.activeSpans.length, 3);
+
+          span3.end();
+          expect(hub.scope.activeSpans.length, 2);
+          expect(hub.scope.getActiveSpan(), equals(span2));
+
+          span2.end();
+          expect(hub.scope.getActiveSpan(), equals(span1));
+
+          span1.end();
+          expect(hub.scope.getActiveSpan(), isNull);
+        });
+
+        test('ending spans out of order removes them from active spans', () {
+          final hub = fixture.getSut();
+
+          final parent = hub.startSpan('parent');
+          final child = hub.startSpan('child');
+
+          parent.end();
+          expect(hub.scope.activeSpans, contains(child));
+          expect(hub.scope.activeSpans, isNot(contains(parent)));
+
+          child.end();
+          expect(hub.scope.activeSpans, isEmpty);
+        });
+
+        test('deep hierarchy maintains correct parent chain', () {
+          final hub = fixture.getSut();
+
+          final spans = <Span>[];
+          for (var i = 0; i < 5; i++) {
+            spans.add(hub.startSpan('span-$i'));
+          }
+
+          // Verify chain: span0 <- span1 <- span2 <- span3 <- span4
+          expect(spans[0].parentSpan, isNull);
+          for (var i = 1; i < spans.length; i++) {
+            expect(spans[i].parentSpan, equals(spans[i - 1]));
+          }
+        });
+      });
     });
 
     group('captureSpan', () {

From 540851decb0a4ab5fd5900b851abd79e059e776f Mon Sep 17 00:00:00 2001
From: Giancarlo Buenaflor <giancarlobuenaflor97@gmail.com>
Date: Wed, 3 Dec 2025 00:05:19 +0100
Subject: [PATCH 16/16] Update

---
 packages/dart/test/hub_span_test.dart | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/packages/dart/test/hub_span_test.dart b/packages/dart/test/hub_span_test.dart
index d9c3e3eba4..5f78608aff 100644
--- a/packages/dart/test/hub_span_test.dart
+++ b/packages/dart/test/hub_span_test.dart
@@ -199,6 +199,26 @@ void main() {
           expect(hub.scope.activeSpans, isEmpty);
         });
 
+        test(
+            'new span parents to active root span when multiple root spans exist',
+            () {
+          final hub = fixture.getSut();
+
+          final activeRoot =
+              hub.startSpan('active-root', parentSpan: null, active: true);
+          final inactiveRoot =
+              hub.startSpan('inactive-root', parentSpan: null, active: false);
+
+          final childToActiveSpan = hub.startSpan('child');
+          expect(childToActiveSpan.parentSpan, equals(activeRoot));
+          expect(childToActiveSpan.parentSpan, isNot(equals(inactiveRoot)));
+
+          final childToInactiveSpan =
+              hub.startSpan('child', parentSpan: inactiveRoot);
+          expect(childToInactiveSpan.parentSpan, equals(inactiveRoot));
+          expect(childToInactiveSpan.parentSpan, isNot(equals(activeRoot)));
+        });
+
         test('deep hierarchy maintains correct parent chain', () {
           final hub = fixture.getSut();