Fix bug when the flag value is null

CHANGELOG.md

@@ -1,3 +1,7 @@
+# 3.1.1 - 16/01/2024
+
+- Return the correct flag value from value() method when nil is given as default value or when the value for flag is null
+
 # 3.1.0 - 08/11/2023
 
 - Troubleshooting mode : If you are experiencing issues while using the SDK, we are now able to gather logs and information to help you.

example/lib/widgets/Modifications.dart

@@ -57,10 +57,7 @@ class _ModificationsState extends State<Modifications> {
 
     myFlag = currentVisitor?.getFlag(keyFlagController.text, defaultValue);
 
-    var ret = myFlag?.value(visitorExposed: false);
-
-    //  var ret =
-    //   currentVisitor?.getModification(keyFlagController.text, defaultValue);
+    var ret = myFlag?.value();
 
     setState(() {
       valueForFlag = ret.toString();

lib/flagship_version.dart

@@ -1,2 +1,2 @@
 /// This file is automatically updated
-const FlagshipVersion = "3.1.0";
+const FlagshipVersion = "3.1.1";

lib/model/flag.dart

@@ -17,28 +17,42 @@ class Flag<T> implements IFlag {
 // Get value for flag
 //
 // visitorExposed is true by default
-  T value({bool visitorExposed = true}) {
+  dynamic value({bool visitorExposed = true}) {
+    dynamic retValue = _defaultValue;
     Modification? modif = this._visitorDelegate.getFlagModification(this._key);
     if (modif != null) {
-      if (_isSameType(modif.value)) {
-        // Activate if necessary
-        if (visitorExposed) {
-          this.visitorExposed();
+      try {
+        {
+          if (modif.value == null) {
+            // Activate if necessary
+            if (visitorExposed) {
+              this.visitorExposed();
+            }
+          } else if (_isSameTypeOrDefaultValueNull(modif.value)) {
+            /// Get the flag value
+            retValue = modif.value;
+            // Activate if necessary
+            if (visitorExposed) {
+              this.visitorExposed();
+            }
+          } else {
+            DataUsageTracking.sharedInstance().proceesTroubleShootingFlag(
+                CriticalPoints.GET_FLAG_VALUE_TYPE_WARNING.name,
+                this,
+                this._visitorDelegate.visitor);
+          }
         }
-        return modif.value as T;
-      } else {
-        DataUsageTracking.sharedInstance().proceesTroubleShootingFlag(
-            CriticalPoints.GET_FLAG_VALUE_TYPE_WARNING.name,
-            this,
-            this._visitorDelegate.visitor);
+      } catch (exp) {
+        Flagship.logger(Level.INFO,
+            "an exception raised  $exp , will return a default value ");
       }
     } else {
       DataUsageTracking.sharedInstance().proceesTroubleShootingFlag(
           CriticalPoints.GET_FLAG_VALUE_FLAG_NOT_FOUND.name,
           this,
           this._visitorDelegate.visitor);
     }
-    return _defaultValue;
+    return retValue;
   }
 
 // Expose Flag
@@ -53,7 +67,8 @@ class Flag<T> implements IFlag {
     Modification? modification =
         this._visitorDelegate.getFlagModification(this._key);
     if (modification != null) {
-      if (modification.value == null || _isSameType(modification.value)) {
+      if (modification.value == null ||
+          _isSameTypeOrDefaultValueNull(modification.value)) {
         Flagship.logger(
             Level.DEBUG, "Send exposure flag (activate) for : " + _key);
 
@@ -81,7 +96,8 @@ class Flag<T> implements IFlag {
   FlagMetadata metadata() {
     // Before expose whe should check the Type
     Modification? modif = this._visitorDelegate.getFlagModification(this._key);
-    if (modif != null && (modif.value == null || _isSameType(modif.value))) {
+    if (modif != null &&
+        (modif.value == null || _isSameTypeOrDefaultValueNull(modif.value))) {
       // when the flag value is null we provide the metadata
       return FlagMetadata.withMap(
           this._visitorDelegate.getModificationInfo(this._key));
@@ -90,8 +106,12 @@ class Flag<T> implements IFlag {
     }
   }
 
-  // Check the type of flag's value with the default value
-  bool _isSameType(dynamic value) {
+  // Check the type of flag's value with the default value and return true if the same
+  // If the default value is null will return true
+  bool _isSameTypeOrDefaultValueNull(dynamic value) {
+    if (this._defaultValue.runtimeType == Null) {
+      return true;
+    }
     return (value is T);
   }
 

pubspec.yaml

@@ -1,6 +1,6 @@
 name: flagship
 description: Flutter SDK for Flagship Feature management & Experiment platform for modern engineering and product teams
-version: 3.1.0
+version: 3.1.1
 homepage: https://flagship.io
 
 environment:

test/flag_test.dart

@@ -212,6 +212,10 @@ void main() async {
     v2.fetchFlags().whenComplete(() {
       Flag myFlag = v2.getFlag("key_A", 3.14);
       expect(myFlag.value(), 3.14);
+
+      Flag myFlagBis = v2.getFlag("key_A", false);
+      expect(myFlagBis.value(), false);
+
       expect(myFlag.exists(), true);
       FlagMetadata metadata = myFlag.metadata();
       expect(metadata.campaignId, "");
@@ -224,12 +228,23 @@ void main() async {
   });
 
   test("Flag with null as value", () {
-    //  PathProviderPlatform.instance = FakePathProviderPlatform();
     var v3 = Flagship.newVisitor("flagVisitor").build();
     v3.fetchFlags().whenComplete(() {
+      // String as default value
       Flag myFlag = v3.getFlag("keyNull", "nullValue");
       expect(myFlag.value(), "nullValue");
+      // bool as default value
+      Flag myFlagBool = v3.getFlag("keyNull", false);
+      expect(myFlagBool.value(), false);
+      // Double as default value
+      Flag myFlagDouble = v3.getFlag("keyNull", 12.0);
+      expect(myFlagDouble.value(), 12.0);
+      // Int as default value
+      Flag myFlagInt = v3.getFlag("keyNull", 2);
+      expect(myFlagInt.value(), 2);
+      // is existing
       expect(myFlag.exists(), true);
+      // Get metadata
       FlagMetadata metadata = myFlag.metadata();
       expect(metadata.campaignId, "bsffhle242b2l3igq4dg");
       expect(metadata.variationGroupId, "bsffhle242b2l3igq4egaa");
@@ -257,6 +272,23 @@ void main() async {
     });
   });
 
+  test("Flag with default value = null", () {
+    //PathProviderPlatform.instance = FakePathProviderPlatform();
+    var v4 = Flagship.newVisitor("flagVisitor").build();
+    v4.fetchFlags().whenComplete(() {
+      Flag myFlag = v4.getFlag("key_A", null);
+      expect(myFlag.value(), "val_A");
+      expect(myFlag.exists(), true);
+      FlagMetadata metadata = myFlag.metadata();
+      expect(metadata.campaignId, "bsffhle242b2l3igq4dg");
+      expect(metadata.variationGroupId, "bsffhle242b2l3igq4egaa");
+      expect(metadata.variationId, "bsffhle242b2l3igq4f0");
+      expect(metadata.isReference, true);
+      expect(metadata.slug, "flutter");
+      expect(metadata.campaignType, "ab");
+    });
+  });
+
   test("Failed Activate Flag", () {
     when(fakeService.sendHttpRequest(RequestType.Post,
             'https://decision.flagship.io/v2/activate', any, any,