refactor(language): name disambiguation

* Use fully qualified names starting with :: (as in C++) to unambiguously refer
  to an element.
* Name shadowing within modules.

2 files changed, 14 insertions, 10 deletions

diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
index 166b4400..fa04a012 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/contentassist/ProblemCrossrefProposalProvider.java
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2023 The Refinery Authors <https://refinery.tools/>
+ * SPDX-FileCopyrightText: 2021-2024 The Refinery Authors <https://refinery.tools/>
  *
  * SPDX-License-Identifier: EPL-2.0
  */
@@ -15,13 +15,14 @@ import org.eclipse.xtext.EcoreUtil2;
 import org.eclipse.xtext.GrammarUtil;
 import org.eclipse.xtext.ide.editor.contentassist.ContentAssistContext;
 import org.eclipse.xtext.ide.editor.contentassist.IdeCrossrefProposalProvider;
-import org.eclipse.xtext.naming.QualifiedName;
 import org.eclipse.xtext.nodemodel.util.NodeModelUtils;
 import org.eclipse.xtext.resource.IEObjectDescription;
 import org.eclipse.xtext.scoping.IScope;
 import org.eclipse.xtext.xtext.CurrentTypeFinder;
 import org.jetbrains.annotations.Nullable;
 import tools.refinery.language.model.problem.*;
+import tools.refinery.language.naming.NamingUtil;
+import tools.refinery.language.naming.ProblemQualifiedNameConverter;
 import tools.refinery.language.resource.ProblemResourceDescriptionStrategy;
 import tools.refinery.language.utils.BuiltinSymbols;
 import tools.refinery.language.utils.ProblemDesugarer;
@@ -46,14 +47,12 @@ public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider
         @Override
         protected Iterable<IEObjectDescription> queryScope(IScope scope, CrossReference crossReference,
                                                                                                            ContentAssistContext context) {
-                var eObjectDescriptionsByName = new HashMap<QualifiedName, List<IEObjectDescription>>();
+                var eObjectDescriptionsByName = new HashMap<ProblemResourceDescriptionStrategy.ShadowingKey,
+                                List<IEObjectDescription>>();
                 for (var candidate : super.queryScope(scope, crossReference, context)) {
                         if (isExistingObject(candidate, crossReference, context)) {
-                                // {@code getQualifiedName()} will refer to the full name for objects that are loaded from the global
-                                // scope, but {@code getName()} returns the qualified name that we set in
-                                // {@code ProblemResourceDescriptionStrategy}.
-                                var qualifiedName = candidate.getName();
-                                var candidateList = eObjectDescriptionsByName.computeIfAbsent(qualifiedName,
+                                var shadowingKey = ProblemResourceDescriptionStrategy.getShadowingKey(candidate);
+                                var candidateList = eObjectDescriptionsByName.computeIfAbsent(shadowingKey,
                                                 ignored -> new ArrayList<>());
                                 candidateList.add(candidate);
                         }
@@ -61,7 +60,7 @@ public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider
                 var eObjectDescriptions = new ArrayList<IEObjectDescription>();
                 for (var candidates : eObjectDescriptionsByName.values()) {
                         if (candidates.size() == 1) {
-                                var candidate = candidates.get(0);
+                                var candidate = candidates.getFirst();
                                 if (shouldBeVisible(candidate, crossReference, context)) {
                                         eObjectDescriptions.add(candidate);
                                 }
@@ -96,6 +95,11 @@ public class ProblemCrossrefProposalProvider extends IdeCrossrefProposalProvider
 
         protected boolean shouldBeVisible(IEObjectDescription candidate, CrossReference crossReference,
                                                                           ContentAssistContext context) {
+                if (NamingUtil.isFullyQualified(candidate.getName()) &&
+                                !context.getPrefix().startsWith(ProblemQualifiedNameConverter.DELIMITER)) {
+                        // Do not propose names with a root prefix unless explicitly asked for.
+                        return false;
+                }
                 var errorPredicate = candidate.getUserData(ProblemResourceDescriptionStrategy.ERROR_PREDICATE);
                 if (ProblemResourceDescriptionStrategy.ERROR_PREDICATE_TRUE.equals(errorPredicate)) {
                         return false;
diff --git a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
index 94a61c4f..891c73c7 100644
--- a/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
+++ b/subprojects/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
@@ -99,7 +99,7 @@ public class ProblemSemanticHighlightingCalculator extends DefaultSemanticHighli
 
         protected String[] getHighlightClass(EObject eObject, EReference reference) {
                 boolean isError = ProblemUtil.isError(eObject);
-                if (ProblemUtil.isBuiltIn(eObject)) {
+                if (ProblemUtil.isBuiltIn(eObject) && !(eObject instanceof Problem)) {
                         var className = isError ? ERROR_CLASS : BUILTIN_CLASS;
                         return new String[]{className};
                 }