refactor: use dart 3 pattern matching

ardera · Jun 20, 2023 · 7f4a1d9 · 7f4a1d9
1 parent ed9bd23
commit 7f4a1d9
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Showing 2 changed files with 30 additions and 40 deletions.
diff --git a/packages/linux_can/lib/src/data_classes.dart b/packages/linux_can/lib/src/data_classes.dart
@@ -435,7 +435,7 @@ abstract class CanFrame {
   }
 }
 
-abstract class CanDataFrame extends CanFrame {
+sealed class CanDataFrame extends CanFrame {
   const CanDataFrame({required this.id, required this.data}) : assert(0 <= data.length && data.length <= 8);
 
   /// CAN ID of the frame.
@@ -444,7 +444,7 @@ abstract class CanDataFrame extends CanFrame {
   final List<int> data;
 }
 
-class CanStandardDataFrame extends CanDataFrame {
+final class CanStandardDataFrame extends CanDataFrame {
   const CanStandardDataFrame({required super.id, required super.data}) : assert(id & ~CAN_SFF_MASK == 0);
 
   @override
@@ -456,7 +456,7 @@ class CanStandardDataFrame extends CanDataFrame {
   int get hashCode => Object.hash(id.hashCode, data.hashCode);
 }
 
-class CanExtendedDataFrame extends CanDataFrame {
+final class CanExtendedDataFrame extends CanDataFrame {
   const CanExtendedDataFrame({required super.id, required super.data}) : assert(id & ~CAN_EFF_MASK == 0);
 
   @override
@@ -468,14 +468,14 @@ class CanExtendedDataFrame extends CanDataFrame {
   int get hashCode => Object.hash(id.hashCode, data.hashCode);
 }
 
-abstract class CanRemoteFrame extends CanFrame {
+sealed class CanRemoteFrame extends CanFrame {
   const CanRemoteFrame({required this.id});
 
   /// CAN ID of the frame.
   final int id;
 }
 
-class CanStandardRemoteFrame extends CanRemoteFrame {
+final class CanStandardRemoteFrame extends CanRemoteFrame {
   const CanStandardRemoteFrame({required super.id}) : assert(id & ~CAN_SFF_MASK == 0);
 
   @override
@@ -487,7 +487,7 @@ class CanStandardRemoteFrame extends CanRemoteFrame {
   int get hashCode => id.hashCode;
 }
 
-class CanExtendedRemoteFrame extends CanRemoteFrame {
+final class CanExtendedRemoteFrame extends CanRemoteFrame {
   const CanExtendedRemoteFrame({required super.id}) : assert(id & ~CAN_EFF_MASK == 0);
 
   @override
@@ -499,14 +499,8 @@ class CanExtendedRemoteFrame extends CanRemoteFrame {
   int get hashCode => id.hashCode;
 }
 
-class CanErrorFrame extends CanFrame {
-  /// The fact that we only have one instance of this means we don't need to implement
-  /// operator ==() and hashCode().
-  const CanErrorFrame._();
-
-  factory CanErrorFrame() {
-    return const CanErrorFrame._();
-  }
+final class CanErrorFrame extends CanFrame {
+  const CanErrorFrame();
 }
 
 /// The RFC2863 state of the network interface.

diff --git a/packages/linux_can/lib/src/platform_interface.dart b/packages/linux_can/lib/src/platform_interface.dart
@@ -426,32 +426,28 @@ class PlatformInterface {
 
     final nativeFrame = ffi.calloc<can_frame>();
 
-    if (frame is CanDataFrame) {
-      nativeFrame.ref.can_id = frame.id;
-      if (frame is CanExtendedDataFrame) {
-        nativeFrame.ref.can_id |= CAN_EFF_FLAG;
-      }
-
-      assert(frame.data.length <= 8);
-
-      nativeFrame.ref.len = frame.data.length;
-      _writeBytesToArray(
-        frame.data,
-        8,
-        (index, value) => nativeFrame.ref.data[index] = value,
-      );
-    } else if (frame is CanRemoteFrame) {
-      nativeFrame.ref.can_id = frame.id;
-      if (frame is CanExtendedRemoteFrame) {
-        nativeFrame.ref.can_id |= CAN_EFF_FLAG;
-      }
-      nativeFrame.ref.can_id |= CAN_RTR_FLAG;
-
-      nativeFrame.ref.len = 0;
-    } else if (frame is CanErrorFrame) {
-      nativeFrame.ref.can_id |= CAN_ERR_FLAG;
-
-      nativeFrame.ref.len = 0;
+    switch (frame) {
+      case CanDataFrame(data: var data):
+        nativeFrame.ref.can_id = switch (frame) {
+          CanStandardDataFrame(id: var id) => id,
+          CanExtendedDataFrame(id: var id) => id | CAN_EFF_FLAG,
+        };
+
+        nativeFrame.ref.len = frame.data.length;
+        _writeBytesToArray(
+          data,
+          8,
+          (index, value) => nativeFrame.ref.data[index] = value,
+        );
+      case CanRemoteFrame _:
+        nativeFrame.ref.can_id = switch (frame) {
+          CanStandardRemoteFrame(id: var id) => id | CAN_RTR_FLAG,
+          CanExtendedRemoteFrame(id: var id) => id | CAN_RTR_FLAG | CAN_EFF_FLAG,
+        };
+        nativeFrame.ref.len = 0;
+      case CanErrorFrame _:
+        nativeFrame.ref.can_id = CAN_ERR_FLAG;
+        nativeFrame.ref.len = 0;
     }
 
     /// TODO: use sendmsg and MSG_DONTWAIT for non-blocking sends, and make blocking sends block in the kernel