diff --git a/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.test.ts b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.test.ts
new file mode 100644
index 0000000000..5655839ad4
--- /dev/null
+++ b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.test.ts
@@ -0,0 +1,20 @@
+import {
+    getDeletedLegalValues,
+    getInvalidLegalValues,
+} from './legal-value-functions';
+
+test('should return deleted legal values', () => {
+    const deletedLegalValues = getDeletedLegalValues(
+        [{ value: 'A' }, { value: 'B' }],
+        ['A', 'C'],
+    );
+    expect([...deletedLegalValues]).toStrictEqual(['C']);
+});
+
+test('should return invalid legal values', () => {
+    const invalidLegalValues = getInvalidLegalValues(
+        (value: string) => value === 'B',
+        [{ value: 'A' }, { value: 'B' }],
+    );
+    expect([...invalidLegalValues]).toEqual(['A']);
+});
diff --git a/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.ts b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.ts
new file mode 100644
index 0000000000..bb07886864
--- /dev/null
+++ b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/legal-value-functions.ts
@@ -0,0 +1,25 @@
+import type { ILegalValue } from 'interfaces/context';
+import { difference } from './set-functions';
+
+export const getDeletedLegalValues = (
+    allLegalValues: ILegalValue[],
+    selectedLegalValues: string[],
+): Set<string> => {
+    const currentLegalValues = new Set(
+        allLegalValues.map(({ value }) => value),
+    );
+    const deletedValues = difference(selectedLegalValues, currentLegalValues);
+
+    return deletedValues;
+};
+
+export const getInvalidLegalValues = (
+    validate: (value: string) => boolean,
+    allLegalValues: ILegalValue[],
+): Set<string> => {
+    return new Set(
+        allLegalValues
+            .filter(({ value }) => !validate(value))
+            .map(({ value }) => value),
+    );
+};
diff --git a/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/useEditableConstraint.tsx b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/useEditableConstraint.tsx
index 76c246074d..ffdfcc0e0c 100644
--- a/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/useEditableConstraint.tsx
+++ b/frontend/src/component/feature/FeatureStrategy/FeatureStrategyConstraints/useEditableConstraint/useEditableConstraint.tsx
@@ -20,7 +20,10 @@ import {
     type ConstraintValidationResult,
     constraintValidator,
 } from './constraint-validator';
-import { difference } from './set-functions';
+import {
+    getDeletedLegalValues,
+    getInvalidLegalValues,
+} from './legal-value-functions';
 
 const resolveContextDefinition = (
     context: IUnleashContextDefinition[],
@@ -88,16 +91,10 @@ export const useEditableConstraint = (
             contextDefinition.legalValues?.length &&
             constraint.values?.length
         ) {
-            // todo: extract and test
-            const currentLegalValues = new Set(
-                contextDefinition.legalValues.map(({ value }) => value),
-            );
-            const deletedValues = difference(
+            return getDeletedLegalValues(
+                contextDefinition.legalValues,
                 constraint.values,
-                currentLegalValues,
             );
-
-            return deletedValues;
         }
         return undefined;
     }, [
@@ -110,11 +107,9 @@ export const useEditableConstraint = (
             contextDefinition.legalValues?.length &&
             isSingleValueConstraint(localConstraint)
         ) {
-            // todo: extract and test
-            return new Set(
-                contextDefinition.legalValues
-                    .filter(({ value }) => !validator(value)[0])
-                    .map(({ value }) => value),
+            return getInvalidLegalValues(
+                (value) => validator(value)[0],
+                contextDefinition.legalValues,
             );
         }
         return undefined;