[2291] Fix item label for constraint to show their name and expression

CHANGELOG.adoc

@@ -30,6 +30,7 @@ It has long been unused by Sirius Web itself (since the transition to MUI).
 - https://github.com/eclipse-syson/syson/issues/2232[#2232] [configuration] Fix a serialization problem of the View models of SysON representations.
 - https://github.com/eclipse-syson/syson/issues/2237[#2237] [diagrams] Fix the item label inside `frames`, `require constraints`, and `assume constraints` compartments.
 - https://github.com/eclipse-syson/syson/issues/2278[#2278] [diagrams] Display inherited behavior parameters in the _parameters_ compartment of `ActionDefinition` and `ActionUsage` graphical nodes.
+- https://github.com/eclipse-syson/syson/issues/2291[#2291] [diagrams] Fix item label for constraint to show their name and expression value between braces (if present).
 
 === Improvements
 

backend/services/syson-diagram-services/src/main/java/org/eclipse/syson/diagram/services/DiagramQueryLabelService.java

@@ -493,10 +493,7 @@ public String getCompartmentItemLabel(Usage usage) {
 
     private String getCompartmentItemStringRepresentation(Usage usage, boolean directEditInput) {
         StringBuilder label = new StringBuilder();
-        if (usage instanceof ConstraintUsage constraintUsage
-                && usage.getOwningMembership() instanceof RequirementConstraintMembership) {
-            // Use the constraint-specific rendering only if the element is a constraint owned by a requirement. Other
-            // constraints (including requirements) are rendered as regular elements.
+        if (usage instanceof ConstraintUsage constraintUsage) {
             label.append(this.getCompartmentItemLabel(constraintUsage, directEditInput));
         } else {
             label.append(this.getUsageListItemPrefix(usage));
@@ -597,11 +594,7 @@ public String getSatisfyLabel(SatisfyRequirementUsage satisfyRequirementUsage) {
      */
     private String getCompartmentItemLabel(ConstraintUsage constraintUsage, boolean directEditInput) {
         StringBuilder label = new StringBuilder();
-        if (constraintUsage == null) {
-            label.append("");
-        } else if (!constraintUsage.getOwnedMember().isEmpty() && constraintUsage.getOwnedMember().get(0) instanceof Expression expression) {
-            label.append(this.getSysmlTextualRepresentation(expression, directEditInput));
-        } else {
+        if (constraintUsage != null) {
             var identificationLabel = this.getIdentificationLabel(constraintUsage);
             if (identificationLabel.isBlank()) {
                 // The constraint doesn't have an expression and does not have a name, we use the referenced feature name if the referenced feature exists
@@ -615,6 +608,14 @@ private String getCompartmentItemLabel(ConstraintUsage constraintUsage, boolean
                 label.append(this.getReferenceSubsettingLabel(constraintUsage));
             }
 
+            if (!directEditInput && !constraintUsage.getOwnedMember().isEmpty() && constraintUsage.getOwnedMember().get(0) instanceof Expression expression) {
+                if (!label.isEmpty()) {
+                    label.append(LabelConstants.SPACE);
+                }
+                label.append(LabelConstants.OPEN_BRACE).append(LabelConstants.SPACE);
+                label.append(this.getSysmlTextualRepresentation(expression, directEditInput));
+                label.append(LabelConstants.SPACE).append(LabelConstants.CLOSE_BRACE);
+            }
         }
         return label.toString();
     }

backend/services/syson-diagram-services/src/test/java/org/eclipse/syson/diagram/services/DiagramQueryLabelServiceTest.java

@@ -333,7 +333,7 @@ public void testGetCompartmentItemLabelOfConstraintWithBooleanExpression() {
         literalInteger.setValue(2);
         yValue.getOwnedRelatedElement().add(literalInteger);
 
-        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo("1 >= 2");
+        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo(CONSTRAINT_USAGE_NAME + " { 1 >= 2 }");
     }
 
     @DisplayName("GIVEN a ConstraintUsage with an expression containing a subject reference, WHEN its label is computed, THEN the label represents the expression")
@@ -356,7 +356,7 @@ public void testGetCompartmentItemLabelOfConstraintWithSubjectReferenceExpressio
         yFeatureReference.getOwnedRelationship().add(yFeatureReferenceMembership);
         yFeatureReferenceMembership.setMemberElement(subjectReference);
 
-        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo("1 >= mySubject");
+        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo(CONSTRAINT_USAGE_NAME + " { 1 >= mySubject }");
 
     }
 
@@ -381,7 +381,7 @@ public void testGetCompartmentItemLabelOfConstraintWithAttributeReferenceExpress
         yFeatureReference.getOwnedRelationship().add(yFeatureReferenceMembership);
         yFeatureReferenceMembership.setMemberElement(attributeUsage);
 
-        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo("1 >= myAttribute");
+        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo(CONSTRAINT_USAGE_NAME + " { 1 >= myAttribute }");
     }
 
     @DisplayName("GIVEN a ConstraintUsage with an expression containing a single feature chaining, WHEN its label is computed, THEN the label represents the expression")
@@ -406,7 +406,7 @@ public void testGetCompartmentItemLabelOfConstraintWithSingleFeatureChainingExpr
         featureChainExpression.getOwnedRelationship().add(featureChainMembership);
         featureChainMembership.setMemberElement(subAttributeUsage);
 
-        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo("1 >= myAttribute.mySubAttribute");
+        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo(CONSTRAINT_USAGE_NAME + " { 1 >= myAttribute.mySubAttribute }");
     }
 
     @DisplayName("GIVEN a ConstraintUsage with an expression containing multiple feature chainings, WHEN its label is computed, THEN the label represents the expression")
@@ -439,7 +439,7 @@ public void testGetCompartmentItemLabelOfConstraintWithMultipleFeatureChainingEx
         featureChaining2.setChainingFeature(zAttributeUsage);
         feature.getOwnedRelationship().addAll(List.of(featureChaining1, featureChaining2));
 
-        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo("1 >= x.y.z");
+        assertThat(this.labelService.getCompartmentItemLabel(constraintUsage)).isEqualTo(CONSTRAINT_USAGE_NAME + " { 1 >= x.y.z }");
     }
 
     @DisplayName("GIVEN a Dependency with a name and short name, WHEN its edge label is computed, THEN the label contains the name and short name")

backend/services/syson-sysml-metamodel-services/src/main/java/org/eclipse/syson/sysml/metamodel/helper/LabelConstants.java

@@ -25,6 +25,8 @@ public class LabelConstants {
 
     public static final String ASSUME = SysMLv2Keywords.ASSUME;
 
+    public static final String CLOSE_BRACE = SysMLv2Keywords.RIGHT_BRACE;
+
     public static final String CLOSE_BRACKET = SysMLv2Keywords.RIGHT_BRACKET;
 
     public static final String CLOSE_PARENTHESIS = SysMLv2Keywords.RIGHT_PAREN;
@@ -63,6 +65,8 @@ public class LabelConstants {
 
     public static final String NON_UNIQUE = SysMLv2Keywords.NONUNIQUE;
 
+    public static final String OPEN_BRACE = SysMLv2Keywords.LEFT_BRACE;
+
     public static final String OPEN_BRACKET = SysMLv2Keywords.LEFT_BRACKET;
 
     public static final String OPEN_PARENTHESIS = SysMLv2Keywords.LEFT_PAREN;