feat(language): warn about partial references

2 files changed, 88 insertions, 0 deletions

diff --git a/subprojects/language/src/main/java/tools/refinery/language/validation/ActionTargetCollector.java b/subprojects/language/src/main/java/tools/refinery/language/validation/ActionTargetCollector.java
new file mode 100644
index 00000000..67cd5777
--- /dev/null
+++ b/subprojects/language/src/main/java/tools/refinery/language/validation/ActionTargetCollector.java
@@ -0,0 +1,73 @@
+/*
+ * SPDX-FileCopyrightText: 2024 The Refinery Authors <https://refinery.tools/>
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ */
+package tools.refinery.language.validation;
+
+import com.google.inject.Inject;
+import com.google.inject.Singleton;
+import org.eclipse.xtext.EcoreUtil2;
+import org.eclipse.xtext.util.IResourceScopeCache;
+import org.eclipse.xtext.util.Tuples;
+import tools.refinery.language.model.problem.*;
+
+import java.util.HashSet;
+import java.util.Set;
+
+@Singleton
+public class ActionTargetCollector {
+        private static final String ACTION_TARGETS =
+                        "tools.refinery.language.validation.ActionTargetCollector.ACTION_TARGETS";
+
+        @Inject
+        private IResourceScopeCache cache = IResourceScopeCache.NullImpl.INSTANCE;
+
+        public boolean isActionTarget(Relation relation) {
+                var problem = EcoreUtil2.getContainerOfType(relation, Problem.class);
+                return problem != null && isActionTarget(problem, relation);
+        }
+
+        public boolean isActionTarget(Problem problem, Relation relation) {
+                var targets = getActionTargets(problem);
+                if (targets.contains(relation)) {
+                        return true;
+                }
+                if (relation instanceof ReferenceDeclaration referenceDeclaration) {
+                        var opposite = referenceDeclaration.getOpposite();
+                        return opposite != null && targets.contains(opposite);
+                }
+                return false;
+        }
+
+        protected Set<Relation> getActionTargets(Problem problem) {
+                var resource = problem.eResource();
+                if (resource == null) {
+                        return doGetActionTargets(problem);
+                }
+                return cache.get(Tuples.create(problem, ACTION_TARGETS), resource, () -> doGetActionTargets(problem));
+        }
+
+        protected Set<Relation> doGetActionTargets(Problem problem) {
+                var targets = new HashSet<Relation>();
+                for (var statement : problem.getStatements()) {
+                        if (statement instanceof RuleDefinition ruleDefinition) {
+                                collectTargets(ruleDefinition, targets);
+                        }
+                }
+                return targets;
+        }
+
+        private static void collectTargets(RuleDefinition ruleDefinition, HashSet<Relation> targets) {
+                for (var consequent : ruleDefinition.getConsequents()) {
+                        for (var action : consequent.getActions()) {
+                                if (action instanceof AssertionAction assertionAction) {
+                                        var target = assertionAction.getRelation();
+                                        if (target != null) {
+                                                targets.add(target);
+                                        }
+                                }
+                        }
+                }
+        }
+}
diff --git a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
index 36a77ac7..84218f17 100644
--- a/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
+++ b/subprojects/language/src/main/java/tools/refinery/language/validation/ProblemValidator.java
@@ -54,6 +54,7 @@ public class ProblemValidator extends AbstractProblemValidator {
         public static final String INVALID_ASSIGNMENT_ISSUE = ISSUE_PREFIX + "INVALID_ASSIGNMENT";
         public static final String TYPE_ERROR = ISSUE_PREFIX + "TYPE_ERROR";
         public static final String VARIABLE_WITHOUT_EXISTS = ISSUE_PREFIX + "VARIABLE_WITHOUT_EXISTS";
+        public static final String UNUSED_PARTIAL_RELATION = ISSUE_PREFIX + "UNUSED_PARTIAL_RELATION";
 
         @Inject
         private ReferenceCounter referenceCounter;
@@ -62,6 +63,9 @@ public class ProblemValidator extends AbstractProblemValidator {
         private ExistsVariableCollector existsVariableCollector;
 
         @Inject
+        private ActionTargetCollector actionTargetCollector;
+
+        @Inject
         private IQualifiedNameConverter qualifiedNameConverter;
 
         @Inject
@@ -336,6 +340,17 @@ public class ProblemValidator extends AbstractProblemValidator {
         }
 
         @Check
+        public void checkPartialReference(ReferenceDeclaration referenceDeclaration) {
+                if (referenceDeclaration.getKind() == ReferenceKind.PARTIAL &&
+                                !actionTargetCollector.isActionTarget(referenceDeclaration)) {
+                        var message = "Add decision or propagation rules to refine partial relation '%s'."
+                                                        .formatted(referenceDeclaration.getName());
+                        acceptWarning(message, referenceDeclaration, ProblemPackage.Literals.REFERENCE_DECLARATION__KIND, 0,
+                                        UNUSED_PARTIAL_RELATION);
+                }
+        }
+
+        @Check
         public void checkSupertypes(ClassDeclaration classDeclaration) {
                 var supertypes = classDeclaration.getSuperTypes();
                 int supertypeCount = supertypes.size();