chore: remove builtin library xtext dependency

26 files changed, 376 insertions, 294 deletions

diff --git a/gradle.properties b/gradle.properties
index c4d174df..5c0df1d3 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,5 +1,6 @@
 ecoreVersion=2.25.0
 ecoreCodegenVersion=2.27.0
+ecoreXmiVersion=2.16.0
 hamcrestVersion=2.2
 jettyVersion=11.0.6
 jmhVersion=1.32
diff --git a/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java b/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
index b2e3c90b..76a67f96 100644
--- a/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
+++ b/language-ide/src/main/java/tools/refinery/language/ide/syntaxcoloring/ProblemSemanticHighlightingCalculator.java
@@ -15,7 +15,7 @@ import org.eclipse.xtext.util.CancelIndicator;
 import com.google.common.collect.ImmutableList;
 import com.google.inject.Inject;
 
-import tools.refinery.language.ProblemUtil;
+import tools.refinery.language.model.ProblemUtil;
 import tools.refinery.language.model.problem.ClassDeclaration;
 import tools.refinery.language.model.problem.EnumDeclaration;
 import tools.refinery.language.model.problem.NamedElement;
diff --git a/language-model/build.gradle b/language-model/build.gradle
index d01f8dfc..46ae839b 100644
--- a/language-model/build.gradle
+++ b/language-model/build.gradle
@@ -1,9 +1,11 @@
 apply plugin: 'java-library'
+apply plugin: 'java-test-fixtures'
 apply from: "${rootDir}/gradle/java-common.gradle"
 apply from: "${rootDir}/gradle/mwe2.gradle"
 
 dependencies {
         api "org.eclipse.emf:org.eclipse.emf.ecore:${ecoreVersion}"
+        api "org.eclipse.emf:org.eclipse.emf.ecore.xmi:${ecoreXmiVersion}"
         mwe2 "org.eclipse.emf:org.eclipse.emf.codegen.ecore:${ecoreCodegenVersion}"
         mwe2 "org.eclipse.emf:org.eclipse.emf.mwe.utils:${mweVersion}"
         mwe2 "org.eclipse.emf:org.eclipse.emf.mwe2.lib:${mwe2Version}"
diff --git a/language-model/plugin.xml b/language-model/plugin.xml
index 1e1a246e..4ca005a8 100644
--- a/language-model/plugin.xml
+++ b/language-model/plugin.xml
@@ -14,4 +14,11 @@
             genModel="src/main/resources/model/problem.genmodel"/>
    </extension>
 
+   <extension point="org.eclipse.emf.ecore.extension_parser">
+      <!-- @generated problem -->
+      <parser
+            type="problem_xmi"
+            class="tools.refinery.language.model.problem.util.ProblemResourceFactoryImpl"/>
+   </extension>
+
 </plugin>
diff --git a/language-model/src/main/java/tools/refinery/language/model/ProblemEMFSetup.java b/language-model/src/main/java/tools/refinery/language/model/ProblemEMFSetup.java
new file mode 100644
index 00000000..9383098b
--- /dev/null
+++ b/language-model/src/main/java/tools/refinery/language/model/ProblemEMFSetup.java
@@ -0,0 +1,34 @@
+package tools.refinery.language.model;
+
+import org.eclipse.emf.ecore.EPackage;
+import org.eclipse.emf.ecore.resource.Resource;
+
+import tools.refinery.language.model.problem.ProblemPackage;
+import tools.refinery.language.model.problem.impl.ProblemFactoryImpl;
+
+public class ProblemEMFSetup {
+        public static final String XMI_RESOURCE_EXTENSION = "problem_xmi";
+
+        private ProblemEMFSetup() {
+                throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
+        }
+
+        // Here we can't rely on java.util.HashMap#putIfAbsent, because
+        // org.eclipse.emf.ecore.impl.EPackageRegistryImpl#containsKey is overridden
+        // without also overriding putIfAbsent. We must make sure to call the
+        // overridden containsKey implementation.
+        @SuppressWarnings("squid:S3824")
+        public static void doEMFRegistration() {
+                if (!EPackage.Registry.INSTANCE.containsKey(ProblemPackage.eNS_URI)) {
+                        EPackage.Registry.INSTANCE.put(ProblemPackage.eNS_URI, ProblemPackage.eINSTANCE);
+                }
+
+                // This Resource.Factory is not actually used once
+                // tools.refinery.language.ProblemStandaloneSetup.createInjectorAndDoEMFRegistration()
+                // is called, because if will be replaced by
+                // tools.refinery.language.resource.ProblemXmiResourceFactory, which implements
+                // org.eclipse.xtext.resource.IResourceFactory as required by Xtext.
+                Resource.Factory.Registry.INSTANCE.getExtensionToFactoryMap().putIfAbsent(XMI_RESOURCE_EXTENSION,
+                                new ProblemFactoryImpl());
+        }
+}
diff --git a/language/src/main/java/tools/refinery/language/ProblemUtil.java b/language-model/src/main/java/tools/refinery/language/model/ProblemUtil.java
index ae2efc3d..b6b199f8 100644
--- a/language/src/main/java/tools/refinery/language/ProblemUtil.java
+++ b/language-model/src/main/java/tools/refinery/language/model/ProblemUtil.java
@@ -1,4 +1,4 @@
-package tools.refinery.language;
+package tools.refinery.language.model;
 
 import java.util.ArrayDeque;
 import java.util.Collection;
@@ -7,11 +7,10 @@ import java.util.HashSet;
 import java.util.Optional;
 import java.util.Set;
 
+import org.eclipse.emf.common.util.URI;
 import org.eclipse.emf.ecore.EObject;
 import org.eclipse.emf.ecore.resource.Resource;
 
-import com.google.common.collect.ImmutableList;
-
 import tools.refinery.language.model.problem.ClassDeclaration;
 import tools.refinery.language.model.problem.Node;
 import tools.refinery.language.model.problem.Problem;
@@ -19,15 +18,18 @@ import tools.refinery.language.model.problem.ProblemPackage;
 import tools.refinery.language.model.problem.ReferenceDeclaration;
 import tools.refinery.language.model.problem.Relation;
 import tools.refinery.language.model.problem.Variable;
-import tools.refinery.language.scoping.ProblemGlobalScopeProvider;
 
 public final class ProblemUtil {
+        public static final String BUILTIN_LIBRARY_NAME = "builtin";
+
+        public static final URI BUILTIN_LIBRARY_URI = getLibraryUri(BUILTIN_LIBRARY_NAME);
+
+        public static final String NODE_CLASS_NAME = "node";
+
         private ProblemUtil() {
                 throw new IllegalStateException("This is a static utility class and should not be instantiated directly");
         }
 
-        public static final String NODE_CLASS_NAME = "node";
-
         public static boolean isSingletonVariable(Variable variable) {
                 return variable.eContainingFeature() == ProblemPackage.Literals.VARIABLE_OR_NODE_ARGUMENT__SINGLETON_VARIABLE;
         }
@@ -44,8 +46,8 @@ public final class ProblemUtil {
 
         public static Optional<Problem> getBuiltInLibrary(EObject context) {
                 return Optional.ofNullable(context.eResource()).map(Resource::getResourceSet)
-                                .map(resourceSet -> resourceSet.getResource(ProblemGlobalScopeProvider.BULTIN_LIBRARY_URI, true))
-                                .map(Resource::getContents).filter(contents -> !contents.isEmpty()).map(contents -> contents.get(0))
+                                .map(resourceSet -> resourceSet.getResource(BUILTIN_LIBRARY_URI, true)).map(Resource::getContents)
+                                .filter(contents -> !contents.isEmpty()).map(contents -> contents.get(0))
                                 .filter(Problem.class::isInstance).map(Problem.class::cast);
         }
 
@@ -53,7 +55,7 @@ public final class ProblemUtil {
                 if (eObject != null) {
                         var eResource = eObject.eResource();
                         if (eResource != null) {
-                                return ProblemGlobalScopeProvider.BULTIN_LIBRARY_URI.equals(eResource.getURI());
+                                return BUILTIN_LIBRARY_URI.equals(eResource.getURI());
                         }
                 }
                 return false;
@@ -85,10 +87,16 @@ public final class ProblemUtil {
         }
 
         public static Collection<ReferenceDeclaration> getAllReferenceDeclarations(ClassDeclaration classDeclaration) {
-                ImmutableList.Builder<ReferenceDeclaration> builder = ImmutableList.builder();
+                Set<ReferenceDeclaration> referenceDeclarations = new HashSet<>();
                 for (ClassDeclaration superclass : getSuperclassesAndSelf(classDeclaration)) {
-                        builder.addAll(superclass.getReferenceDeclarations());
+                        referenceDeclarations.addAll(superclass.getReferenceDeclarations());
                 }
-                return builder.build();
+                return referenceDeclarations;
+        }
+
+        private static URI getLibraryUri(String libraryName) {
+                return URI.createURI(ProblemUtil.class.getClassLoader()
+                                .getResource("model/" + libraryName + "." + ProblemEMFSetup.XMI_RESOURCE_EXTENSION)
+                                .toString());
         }
 }
diff --git a/language-model/src/main/resources/model/builtin.problem_xmi b/language-model/src/main/resources/model/builtin.problem_xmi
new file mode 100644
index 00000000..9255ab66
--- /dev/null
+++ b/language-model/src/main/resources/model/builtin.problem_xmi
@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<problem:Problem
+    xmi:version="2.0"
+    xmlns:xmi="http://www.omg.org/XMI"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns:problem="https://refinery.tools/emf/2021/Problem"
+    xsi:schemaLocation="https://refinery.tools/emf/2021/Problem problem.ecore"
+    name="builtin">
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="node"
+      abstract="true">
+    <referenceDeclarations
+        name="equals"
+        referenceType="//@statements.0"
+        opposite="//@statements.0/@referenceDeclarations.0">
+      <multiplicity
+          xsi:type="problem:UnboundedMultiplicity"/>
+    </referenceDeclarations>
+  </statements>
+  <statements
+      xsi:type="problem:PredicateDefinition"
+      name="exists">
+    <parameters
+        name="node"
+        parameterType="//@statements.0"/>
+  </statements>
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="domain"
+      abstract="true"
+      superTypes="//@statements.0"/>
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="data"
+      abstract="true"
+      superTypes="//@statements.0"/>
+  <statements
+      xsi:type="problem:EnumDeclaration"
+      name="bool">
+    <literals
+        name="false"/>
+    <literals
+        name="true"/>
+  </statements>
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="real"
+      superTypes="//@statements.3">
+    <newNode
+        name="new"/>
+  </statements>
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="int"
+      superTypes="//@statements.3">
+    <newNode
+        name="new"/>
+  </statements>
+  <statements
+      xsi:type="problem:ClassDeclaration"
+      name="string"
+      superTypes="//@statements.3">
+    <newNode
+        name="new"/>
+  </statements>
+</problem:Problem>
diff --git a/language-model/src/main/resources/model/problem.ecore b/language-model/src/main/resources/model/problem.ecore
index a62590ac..e86f0afd 100644
--- a/language-model/src/main/resources/model/problem.ecore
+++ b/language-model/src/main/resources/model/problem.ecore
@@ -1,7 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <ecore:EPackage xmi:version="2.0" xmlns:xmi="http://www.omg.org/XMI" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xmlns:ecore="http://www.eclipse.org/emf/2002/Ecore" name="problem" nsURI="https://refinery.tools/emf/2021/Problem"
-    nsPrefix="problem">
+    xmlns:ecore="http://www.eclipse.org/emf/2002/Ecore" name="problem" nsURI="https://refinery.tools/emf/2021/Problem" nsPrefix="problem">
   <eClassifiers xsi:type="ecore:EClass" name="Problem" eSuperTypes="#//NamedElement">
     <eStructuralFeatures xsi:type="ecore:EReference" name="nodes" upperBound="-1"
         eType="#//Node" containment="true"/>
diff --git a/language-model/src/main/resources/model/problem.genmodel b/language-model/src/main/resources/model/problem.genmodel
index e529977f..057b4917 100644
--- a/language-model/src/main/resources/model/problem.genmodel
+++ b/language-model/src/main/resources/model/problem.genmodel
@@ -8,8 +8,8 @@
     copyrightFields="false" operationReflection="true" importOrganizing="true">
   <foreignModel>problem.ecore</foreignModel>
   <testsDirectory xsi:nil="true"/>
-  <genPackages prefix="Problem" basePackage="tools.refinery.language.model"
-      disposableProviderFactory="true" ecorePackage="problem.ecore#/">
+  <genPackages prefix="Problem" basePackage="tools.refinery.language.model" resource="XMI"
+      disposableProviderFactory="true" fileExtensions="problem_xmi" ecorePackage="problem.ecore#/">
     <genEnums typeSafeEnumCompatible="false" ecoreEnum="problem.ecore#//LogicValue">
       <genEnumLiterals ecoreEnumLiteral="problem.ecore#//LogicValue/TRUE"/>
       <genEnumLiterals ecoreEnumLiteral="problem.ecore#//LogicValue/FALSE"/>
diff --git a/language-model/src/testFixtures/java/tools/refinery/language/model/tests/ProblemTestUtil.java b/language-model/src/testFixtures/java/tools/refinery/language/model/tests/ProblemTestUtil.java
new file mode 100644
index 00000000..b412ed1f
--- /dev/null
+++ b/language-model/src/testFixtures/java/tools/refinery/language/model/tests/ProblemTestUtil.java
@@ -0,0 +1,154 @@
+package tools.refinery.language.model.tests;
+
+import java.util.List;
+import java.util.stream.Stream;
+
+import org.eclipse.emf.ecore.resource.Resource.Diagnostic;
+import org.eclipse.emf.ecore.util.EcoreUtil;
+
+import tools.refinery.language.model.ProblemUtil;
+import tools.refinery.language.model.problem.Argument;
+import tools.refinery.language.model.problem.Assertion;
+import tools.refinery.language.model.problem.AssertionArgument;
+import tools.refinery.language.model.problem.Atom;
+import tools.refinery.language.model.problem.ClassDeclaration;
+import tools.refinery.language.model.problem.Conjunction;
+import tools.refinery.language.model.problem.EnumDeclaration;
+import tools.refinery.language.model.problem.Literal;
+import tools.refinery.language.model.problem.NamedElement;
+import tools.refinery.language.model.problem.NegativeLiteral;
+import tools.refinery.language.model.problem.Node;
+import tools.refinery.language.model.problem.NodeAssertionArgument;
+import tools.refinery.language.model.problem.NodeValueAssertion;
+import tools.refinery.language.model.problem.Parameter;
+import tools.refinery.language.model.problem.PredicateDefinition;
+import tools.refinery.language.model.problem.Problem;
+import tools.refinery.language.model.problem.ReferenceDeclaration;
+import tools.refinery.language.model.problem.Relation;
+import tools.refinery.language.model.problem.Statement;
+import tools.refinery.language.model.problem.UniqueDeclaration;
+import tools.refinery.language.model.problem.Variable;
+import tools.refinery.language.model.problem.VariableOrNode;
+import tools.refinery.language.model.problem.VariableOrNodeArgument;
+
+public class ProblemTestUtil {
+        public Problem builtin(Problem problem) {
+                return ProblemUtil.getBuiltInLibrary(problem).get();
+        }
+
+        public List<Diagnostic> errors(Problem problem) {
+                EcoreUtil.resolveAll(problem);
+                return problem.eResource().getErrors();
+        }
+
+        public List<String> nodeNames(Problem problem) {
+                return problem.getNodes().stream().map(node -> node.getName()).toList();
+        }
+
+        public PredicateDefinition pred(Problem problem, String name) {
+                return namedStatementOfType(problem, PredicateDefinition.class, name);
+        }
+
+        public Parameter param(PredicateDefinition definition, int i) {
+                return definition.getParameters().get(i);
+        }
+
+        public Conjunction conj(PredicateDefinition definition, int i) {
+                return definition.getBodies().get(i);
+        }
+
+        public Literal lit(Conjunction conjunction, int i) {
+                return conjunction.getLiterals().get(i);
+        }
+
+        public Atom negated(Literal literal) {
+                return ((NegativeLiteral) literal).getAtom();
+        }
+
+        public Relation relation(Literal literal) {
+                return ((Atom) literal).getRelation();
+        }
+
+        public Argument arg(Atom atom, int i) {
+                return atom.getArguments().get(i);
+        }
+
+        public Argument arg(Literal literal, int i) {
+                return arg((Atom) literal, i);
+        }
+
+        public VariableOrNode variableOrNode(Argument argument) {
+                return ((VariableOrNodeArgument) argument).getVariableOrNode();
+        }
+
+        public Variable variable(Argument argument) {
+                return (Variable) variableOrNode(argument);
+        }
+
+        public Node node(Argument argument) {
+                return (Node) variableOrNode(argument);
+        }
+
+        public Assertion assertion(Problem problem, int i) {
+                return nthStatementOfType(problem, Assertion.class, i);
+        }
+
+        public AssertionArgument arg(Assertion assertion, int i) {
+                return assertion.getArguments().get(i);
+        }
+
+        public Node node(AssertionArgument argument) {
+                return ((NodeAssertionArgument) argument).getNode();
+        }
+
+        public Node node(Problem problem, String name) {
+                return named(problem.getNodes(), name);
+        }
+
+        public Node uniqueNode(Problem problem, String name) {
+                var uniqueNodes = statementsOfType(problem, UniqueDeclaration.class)
+                                .flatMap(declaration -> declaration.getNodes().stream());
+                return named(uniqueNodes, name);
+        }
+
+        public NodeValueAssertion nodeValueAssertion(Problem problem, int i) {
+                return nthStatementOfType(problem, NodeValueAssertion.class, i);
+        }
+
+        public ClassDeclaration findClass(Problem problem, String name) {
+                return namedStatementOfType(problem, ClassDeclaration.class, name);
+        }
+
+        public ReferenceDeclaration reference(ClassDeclaration declaration, String name) {
+                return named(declaration.getReferenceDeclarations(), name);
+        }
+
+        public EnumDeclaration findEnum(Problem problem, String name) {
+                return namedStatementOfType(problem, EnumDeclaration.class, name);
+        }
+
+        public Node literal(EnumDeclaration declaration, String name) {
+                return named(declaration.getLiterals(), name);
+        }
+
+        private <T extends NamedElement> T named(Stream<? extends T> stream, String name) {
+                return stream.filter(statement -> name.equals(statement.getName())).findAny().get();
+        }
+
+        private <T extends NamedElement> T named(List<? extends T> list, String name) {
+                return named(list.stream(), name);
+        }
+
+        private <T extends Statement> Stream<T> statementsOfType(Problem problem, Class<? extends T> type) {
+                return problem.getStatements().stream().filter(type::isInstance).map(type::cast);
+        }
+
+        private <T extends Statement & NamedElement> T namedStatementOfType(Problem problem, Class<? extends T> type,
+                        String name) {
+                return named(statementsOfType(problem, type), name);
+        }
+
+        private <T extends Statement> T nthStatementOfType(Problem problem, Class<? extends T> type, int n) {
+                return statementsOfType(problem, type).skip(n).findFirst().get();
+        }
+}
diff --git a/language-to-store/src/main/java/tools/refinery/language/mapping/PartialModelMapper.java b/language-to-store/src/main/java/tools/refinery/language/mapping/PartialModelMapper.java
index 2ace27f4..d37c9ec7 100644
--- a/language-to-store/src/main/java/tools/refinery/language/mapping/PartialModelMapper.java
+++ b/language-to-store/src/main/java/tools/refinery/language/mapping/PartialModelMapper.java
@@ -7,7 +7,7 @@ import java.util.Optional;
 
 import org.eclipse.emf.common.util.EList;
 
-import tools.refinery.language.ProblemUtil;
+import tools.refinery.language.model.ProblemUtil;
 import tools.refinery.language.model.problem.Assertion;
 import tools.refinery.language.model.problem.AssertionArgument;
 import tools.refinery.language.model.problem.ClassDeclaration;
diff --git a/language-to-store/src/test/java/tools/refinery/language/mapping/tests/PartialModelMapperTest.xtend b/language-to-store/src/test/java/tools/refinery/language/mapping/tests/PartialModelMapperTest.xtend
index 86dd47ae..dcdea332 100644
--- a/language-to-store/src/test/java/tools/refinery/language/mapping/tests/PartialModelMapperTest.xtend
+++ b/language-to-store/src/test/java/tools/refinery/language/mapping/tests/PartialModelMapperTest.xtend
@@ -10,6 +10,7 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.^extension.ExtendWith
 import tools.refinery.language.mapping.PartialModelMapper
 import tools.refinery.language.model.problem.Problem
+import tools.refinery.language.model.tests.ProblemTestUtil
 import tools.refinery.language.tests.ProblemInjectorProvider
 import tools.refinery.store.model.Tuple
 import tools.refinery.store.model.representation.TruthValue
diff --git a/language-to-store/src/test/java/tools/refinery/language/mapping/tests/ProblemTestUtil.xtend b/language-to-store/src/test/java/tools/refinery/language/mapping/tests/ProblemTestUtil.xtend
deleted file mode 100644
index b3b8145e..00000000
--- a/language-to-store/src/test/java/tools/refinery/language/mapping/tests/ProblemTestUtil.xtend
+++ /dev/null
@@ -1,114 +0,0 @@
-package tools.refinery.language.mapping.tests
-
-import tools.refinery.language.ProblemUtil
-import tools.refinery.language.model.problem.Argument
-import tools.refinery.language.model.problem.Assertion
-import tools.refinery.language.model.problem.AssertionArgument
-import tools.refinery.language.model.problem.Atom
-import tools.refinery.language.model.problem.ClassDeclaration
-import tools.refinery.language.model.problem.Conjunction
-import tools.refinery.language.model.problem.EnumDeclaration
-import tools.refinery.language.model.problem.Literal
-import tools.refinery.language.model.problem.NegativeLiteral
-import tools.refinery.language.model.problem.Node
-import tools.refinery.language.model.problem.NodeAssertionArgument
-import tools.refinery.language.model.problem.NodeValueAssertion
-import tools.refinery.language.model.problem.PredicateDefinition
-import tools.refinery.language.model.problem.Problem
-import tools.refinery.language.model.problem.UniqueDeclaration
-import tools.refinery.language.model.problem.Variable
-import tools.refinery.language.model.problem.VariableOrNodeArgument
-
-class ProblemTestUtil {
-        def builtin(Problem it) {
-                ProblemUtil.getBuiltInLibrary(it).get
-        }
-        
-        def errors(Problem it) {
-                eResource.errors
-        }
-        
-        def nodeNames(Problem it) {
-                nodes.map[name]
-        }
-        
-        def pred(Problem it, String name) {
-                statements.filter(PredicateDefinition).findFirst[it.name == name]
-        }
-        
-        def param(PredicateDefinition it, int i) {
-                parameters.get(i)
-        } 
-
-        def conj(PredicateDefinition it, int i) {
-                bodies.get(i)
-        }
-
-        def lit(Conjunction it, int i) {
-                literals.get(i)
-        }
-
-        def negated(Literal it) {
-                (it as NegativeLiteral).atom
-        }
-
-        def relation(Literal it) {
-                (it as Atom).relation
-        }
-
-        def arg(Atom it, int i) {
-                it.arguments.get(i)
-        }
-
-        def arg(Literal it, int i) {
-                (it as Atom).arg(i)
-        }
-
-        def variable(Argument it) {
-                (it as VariableOrNodeArgument).variableOrNode as Variable
-        }
-
-        def node(Argument it) {
-                (it as VariableOrNodeArgument).variableOrNode as Node
-        }
-        
-        def assertion(Problem it, int i) {
-                statements.filter(Assertion).get(i)
-        }
-        
-        def nodeValueAssertion(Problem it, int i) {
-                statements.filter(NodeValueAssertion).get(i)
-        }
-        
-        def arg(Assertion it, int i) {
-                arguments.get(i)
-        }
-        
-        def node(AssertionArgument it) {
-                (it as NodeAssertionArgument).node
-        }
-        
-        def node(Problem it, String name) {
-                nodes.findFirst[it.name == name]
-        }
-        
-        def uniqueNode(Problem it, String name) {
-                statements.filter(UniqueDeclaration).flatMap[nodes].findFirst[it.name == name]
-        }
-        
-        def findClass(Problem it, String name) {
-                statements.filter(ClassDeclaration).findFirst[it.name == name]
-        }
-        
-        def reference(ClassDeclaration it, String name) {
-                it.referenceDeclarations.findFirst[it.name == name]
-        }
-        
-        def findEnum(Problem it, String name) {
-                statements.filter(EnumDeclaration).findFirst[it.name == name]
-        }
-        
-        def literal(EnumDeclaration it, String name) {
-                literals.findFirst[it.name == name]
-        }
-}
diff --git a/language/build.gradle b/language/build.gradle
index 85b0902f..f2b20ab5 100644
--- a/language/build.gradle
+++ b/language/build.gradle
@@ -12,6 +12,7 @@ dependencies {
         api "org.eclipse.emf:org.eclipse.emf.ecore:${ecoreVersion}"
         api project(':refinery-language-model')
         testFixturesApi "org.eclipse.xtext:org.eclipse.xtext.testing:${xtextVersion}"
+        testFixturesApi testFixtures(project(':refinery-language-model'))
         mwe2 "org.eclipse.xtext:org.eclipse.xtext.common.types:${xtextVersion}"
         mwe2 "org.eclipse.xtext:org.eclipse.xtext.xtext.generator:${xtextVersion}"
         mwe2 "org.eclipse.xtext:xtext-antlr-generator:${xtextAntlrGeneratorVersion}"
diff --git a/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java b/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
index f49069a5..d753a119 100644
--- a/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
+++ b/language/src/main/java/tools/refinery/language/ProblemStandaloneSetup.java
@@ -3,11 +3,14 @@
  */
 package tools.refinery.language;
 
-import org.eclipse.emf.ecore.EPackage;
+import org.eclipse.emf.ecore.resource.Resource;
+import org.eclipse.xtext.resource.IResourceFactory;
+import org.eclipse.xtext.resource.IResourceServiceProvider;
 
+import com.google.inject.Guice;
 import com.google.inject.Injector;
 
-import tools.refinery.language.model.problem.ProblemPackage;
+import tools.refinery.language.model.ProblemEMFSetup;
 
 /**
  * Initialization support for running Xtext languages without Equinox extension
@@ -20,15 +23,22 @@ public class ProblemStandaloneSetup extends ProblemStandaloneSetupGenerated {
         }
 
         @Override
-        // Here we can't rely on java.util.HashMap#computeIfAbsent, because
-        // org.eclipse.emf.ecore.impl.EPackageRegistryImpl#containsKey is overridden
-        // without also overriding computeIfAbsent. We must make sure to call the
-        // overridden containsKey implementation.
-        @SuppressWarnings("squid:S3824")
         public Injector createInjectorAndDoEMFRegistration() {
-                if (!EPackage.Registry.INSTANCE.containsKey(ProblemPackage.eNS_URI)) {
-                        EPackage.Registry.INSTANCE.put(ProblemPackage.eNS_URI, ProblemPackage.eINSTANCE);
-                }
+                ProblemEMFSetup.doEMFRegistration();
+                var xmiInjector = createXmiInjector();
+                registerXmiInjector(xmiInjector);
                 return super.createInjectorAndDoEMFRegistration();
         }
+        
+        protected Injector createXmiInjector() {
+                return Guice.createInjector(new ProblemXmiRuntimeModule());
+        }
+
+        protected void registerXmiInjector(Injector injector) {
+                IResourceFactory resourceFactory = injector.getInstance(IResourceFactory.class);
+                IResourceServiceProvider serviceProvider = injector.getInstance(IResourceServiceProvider.class);
+                
+                Resource.Factory.Registry.INSTANCE.getExtensionToFactoryMap().put(ProblemEMFSetup.XMI_RESOURCE_EXTENSION, resourceFactory);
+                IResourceServiceProvider.Registry.INSTANCE.getExtensionToFactoryMap().put(ProblemEMFSetup.XMI_RESOURCE_EXTENSION, serviceProvider);
+        }
 }
diff --git a/language/src/main/java/tools/refinery/language/ProblemXmiRuntimeModule.java b/language/src/main/java/tools/refinery/language/ProblemXmiRuntimeModule.java
new file mode 100644
index 00000000..03a33bee
--- /dev/null
+++ b/language/src/main/java/tools/refinery/language/ProblemXmiRuntimeModule.java
@@ -0,0 +1,35 @@
+package tools.refinery.language;
+
+import org.eclipse.xtext.naming.IQualifiedNameConverter;
+import org.eclipse.xtext.resource.IDefaultResourceDescriptionStrategy;
+import org.eclipse.xtext.resource.IResourceFactory;
+import org.eclipse.xtext.resource.generic.AbstractGenericResourceRuntimeModule;
+
+import tools.refinery.language.model.ProblemEMFSetup;
+import tools.refinery.language.naming.ProblemQualifiedNameConverter;
+import tools.refinery.language.resource.ProblemResourceDescriptionStrategy;
+import tools.refinery.language.resource.ProblemXmiResourceFactory;
+
+public class ProblemXmiRuntimeModule extends AbstractGenericResourceRuntimeModule {
+        @Override
+        protected String getLanguageName() {
+                return "tools.refinery.language.ProblemXmi";
+        }
+
+        @Override
+        protected String getFileExtensions() {
+                return ProblemEMFSetup.XMI_RESOURCE_EXTENSION;
+        }
+        
+        public Class<? extends IResourceFactory> bindIResourceFactory() {
+                return ProblemXmiResourceFactory.class;
+        }
+        
+        public Class<? extends IQualifiedNameConverter> bindIQualifiedNameConverter() {
+                return ProblemQualifiedNameConverter.class;
+        }
+
+        public Class<? extends IDefaultResourceDescriptionStrategy> bindIDefaultResourceDescriptionStrategy() {
+                return ProblemResourceDescriptionStrategy.class;
+        }
+}
diff --git a/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java b/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
index f6a3ec75..b51de05d 100644
--- a/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
+++ b/language/src/main/java/tools/refinery/language/resource/ProblemLocationInFileProvider.java
@@ -4,7 +4,7 @@ import org.eclipse.emf.ecore.EObject;
 import org.eclipse.xtext.resource.DefaultLocationInFileProvider;
 import org.eclipse.xtext.util.ITextRegion;
 
-import tools.refinery.language.ProblemUtil;
+import tools.refinery.language.model.ProblemUtil;
 import tools.refinery.language.model.problem.ImplicitVariable;
 import tools.refinery.language.model.problem.Node;
 
diff --git a/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java b/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
index c5dea671..e745b6a5 100644
--- a/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
+++ b/language/src/main/java/tools/refinery/language/resource/ProblemResourceDescriptionStrategy.java
@@ -12,7 +12,7 @@ import org.eclipse.xtext.util.IAcceptor;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
 
-import tools.refinery.language.ProblemUtil;
+import tools.refinery.language.model.ProblemUtil;
 import tools.refinery.language.model.problem.NamedElement;
 import tools.refinery.language.model.problem.Node;
 import tools.refinery.language.model.problem.Problem;
diff --git a/language/src/main/java/tools/refinery/language/resource/ProblemXmiResourceFactory.java b/language/src/main/java/tools/refinery/language/resource/ProblemXmiResourceFactory.java
new file mode 100644
index 00000000..68aa6016
--- /dev/null
+++ b/language/src/main/java/tools/refinery/language/resource/ProblemXmiResourceFactory.java
@@ -0,0 +1,16 @@
+package tools.refinery.language.resource;
+
+import org.eclipse.emf.common.util.URI;
+import org.eclipse.emf.ecore.resource.Resource;
+import org.eclipse.xtext.resource.IResourceFactory;
+
+import tools.refinery.language.model.problem.util.ProblemResourceFactoryImpl;
+
+public class ProblemXmiResourceFactory implements IResourceFactory {
+        private Resource.Factory problemResourceFactory = new ProblemResourceFactoryImpl();
+        
+        @Override
+        public Resource createResource(URI uri) {
+                return problemResourceFactory.createResource(uri);
+        }
+}
diff --git a/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java b/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
index a21c3bd2..b582d16b 100644
--- a/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
+++ b/language/src/main/java/tools/refinery/language/scoping/ProblemGlobalScopeProvider.java
@@ -6,20 +6,13 @@ import org.eclipse.emf.common.util.URI;
 import org.eclipse.emf.ecore.resource.Resource;
 import org.eclipse.xtext.scoping.impl.ImportUriGlobalScopeProvider;
 
-public class ProblemGlobalScopeProvider extends ImportUriGlobalScopeProvider {
-        public static final String BUILTIN_LIBRARY_NAME = "builtin";
-
-        public static final URI BULTIN_LIBRARY_URI = getLibraryUri(BUILTIN_LIBRARY_NAME);
+import tools.refinery.language.model.ProblemUtil;
 
+public class ProblemGlobalScopeProvider extends ImportUriGlobalScopeProvider {
         @Override
         protected LinkedHashSet<URI> getImportedUris(Resource resource) {
                 LinkedHashSet<URI> importedUris = new LinkedHashSet<>();
-                importedUris.add(BULTIN_LIBRARY_URI);
+                importedUris.add(ProblemUtil.BUILTIN_LIBRARY_URI);
                 return importedUris;
         }
-
-        private static URI getLibraryUri(String libraryName) {
-                return URI.createURI(ProblemGlobalScopeProvider.class.getClassLoader()
-                                .getResource("tools/refinery/" + libraryName + ".problem").toString());
-        }
 }
diff --git a/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java b/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
index 05a3bcf9..85797025 100644
--- a/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
+++ b/language/src/main/java/tools/refinery/language/scoping/ProblemLocalScopeProvider.java
@@ -13,9 +13,11 @@ import org.eclipse.xtext.scoping.impl.ImportedNamespaceAwareLocalScopeProvider;
 
 import com.google.inject.Inject;
 
+import tools.refinery.language.model.ProblemUtil;
+
 public class ProblemLocalScopeProvider extends ImportedNamespaceAwareLocalScopeProvider {
         private static final QualifiedName BUILTIN_LIBRARY_QUALIFIED_NAME = QualifiedName
-                        .create(ProblemGlobalScopeProvider.BUILTIN_LIBRARY_NAME);
+                        .create(ProblemUtil.BUILTIN_LIBRARY_NAME);
 
         @Inject
         private IResourceDescriptionsProvider resourceDescriptionsProvider;
diff --git a/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java b/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
index 61a3c8f9..86b39dbc 100644
--- a/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
+++ b/language/src/main/java/tools/refinery/language/scoping/ProblemScopeProvider.java
@@ -12,7 +12,7 @@ import org.eclipse.xtext.EcoreUtil2;
 import org.eclipse.xtext.scoping.IScope;
 import org.eclipse.xtext.scoping.Scopes;
 
-import tools.refinery.language.ProblemUtil;
+import tools.refinery.language.model.ProblemUtil;
 import tools.refinery.language.model.problem.ClassDeclaration;
 import tools.refinery.language.model.problem.ExistentialQuantifier;
 import tools.refinery.language.model.problem.PredicateDefinition;
diff --git a/language/src/main/resources/tools/refinery/builtin.problem b/language/src/main/resources/tools/refinery/builtin.problem
deleted file mode 100644
index 7c4f6685..00000000
--- a/language/src/main/resources/tools/refinery/builtin.problem
+++ /dev/null
@@ -1,21 +0,0 @@
-problem builtin.
-
-abstract class node {
-        node[] equals opposite equals
-}
-
-pred exists(node node).
-
-abstract class domain extends node.
-
-abstract class data extends node.
-
-enum bool {
-        true, false
-}
-
-class real extends data.
-
-class int extends data.
-
-class string extends data.
diff --git a/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.xtend b/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.xtend
index 9bd728d6..99cf0a86 100644
--- a/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.xtend
+++ b/language/src/test/java/tools/refinery/language/tests/ProblemParsingTest.xtend
@@ -10,6 +10,7 @@ import org.eclipse.xtext.testing.util.ParseHelper
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.^extension.ExtendWith
 import tools.refinery.language.model.problem.Problem
+import tools.refinery.language.model.tests.ProblemTestUtil
 
 import static org.hamcrest.MatcherAssert.assertThat
 import static org.hamcrest.Matchers.*
@@ -19,10 +20,10 @@ import static org.hamcrest.Matchers.*
 class ProblemParsingTest {
         @Inject
         ParseHelper<Problem> parseHelper
-        
+
         @Inject
         extension ProblemTestUtil
-        
+
         @Test
         def void exampleTest() {
                 val it = parseHelper.parse('''
diff --git a/language/src/test/java/tools/refinery/language/tests/ProblemTestUtil.xtend b/language/src/test/java/tools/refinery/language/tests/ProblemTestUtil.xtend
deleted file mode 100644
index 46418892..00000000
--- a/language/src/test/java/tools/refinery/language/tests/ProblemTestUtil.xtend
+++ /dev/null
@@ -1,114 +0,0 @@
-package tools.refinery.language.tests
-
-import tools.refinery.language.ProblemUtil
-import tools.refinery.language.model.problem.Argument
-import tools.refinery.language.model.problem.Assertion
-import tools.refinery.language.model.problem.AssertionArgument
-import tools.refinery.language.model.problem.Atom
-import tools.refinery.language.model.problem.ClassDeclaration
-import tools.refinery.language.model.problem.Conjunction
-import tools.refinery.language.model.problem.EnumDeclaration
-import tools.refinery.language.model.problem.Literal
-import tools.refinery.language.model.problem.NegativeLiteral
-import tools.refinery.language.model.problem.Node
-import tools.refinery.language.model.problem.NodeAssertionArgument
-import tools.refinery.language.model.problem.NodeValueAssertion
-import tools.refinery.language.model.problem.PredicateDefinition
-import tools.refinery.language.model.problem.Problem
-import tools.refinery.language.model.problem.UniqueDeclaration
-import tools.refinery.language.model.problem.Variable
-import tools.refinery.language.model.problem.VariableOrNodeArgument
-
-class ProblemTestUtil {
-        def builtin(Problem it) {
-                ProblemUtil.getBuiltInLibrary(it).get
-        }
-        
-        def errors(Problem it) {
-                eResource.errors
-        }
-        
-        def nodeNames(Problem it) {
-                nodes.map[name]
-        }
-        
-        def pred(Problem it, String name) {
-                statements.filter(PredicateDefinition).findFirst[it.name == name]
-        }
-        
-        def param(PredicateDefinition it, int i) {
-                parameters.get(i)
-        } 
-
-        def conj(PredicateDefinition it, int i) {
-                bodies.get(i)
-        }
-
-        def lit(Conjunction it, int i) {
-                literals.get(i)
-        }
-
-        def negated(Literal it) {
-                (it as NegativeLiteral).atom
-        }
-
-        def relation(Literal it) {
-                (it as Atom).relation
-        }
-
-        def arg(Atom it, int i) {
-                it.arguments.get(i)
-        }
-
-        def arg(Literal it, int i) {
-                (it as Atom).arg(i)
-        }
-
-        def variable(Argument it) {
-                (it as VariableOrNodeArgument).variableOrNode as Variable
-        }
-
-        def node(Argument it) {
-                (it as VariableOrNodeArgument).variableOrNode as Node
-        }
-        
-        def assertion(Problem it, int i) {
-                statements.filter(Assertion).get(i)
-        }
-        
-        def nodeValueAssertion(Problem it, int i) {
-                statements.filter(NodeValueAssertion).get(i)
-        }
-        
-        def arg(Assertion it, int i) {
-                arguments.get(i)
-        }
-        
-        def node(AssertionArgument it) {
-                (it as NodeAssertionArgument).node
-        }
-        
-        def node(Problem it, String name) {
-                nodes.findFirst[it.name == name]
-        }
-        
-        def uniqueNode(Problem it, String name) {
-                statements.filter(UniqueDeclaration).flatMap[nodes].findFirst[it.name == name]
-        }
-        
-        def findClass(Problem it, String name) {
-                statements.filter(ClassDeclaration).findFirst[it.name == name]
-        }
-        
-        def reference(ClassDeclaration it, String name) {
-                it.referenceDeclarations.findFirst[it.name == name]
-        }
-        
-        def findEnum(Problem it, String name) {
-                statements.filter(EnumDeclaration).findFirst[it.name == name]
-        }
-        
-        def literal(EnumDeclaration it, String name) {
-                literals.findFirst[it.name == name]
-        }
-}
diff --git a/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.xtend b/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.xtend
index ab3e325f..5ff7a2c9 100644
--- a/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.xtend
+++ b/language/src/test/java/tools/refinery/language/tests/scoping/NodeScopingTest.xtend
@@ -12,8 +12,8 @@ import org.junit.jupiter.params.provider.Arguments
 import org.junit.jupiter.params.provider.MethodSource
 import org.junit.jupiter.params.provider.ValueSource
 import tools.refinery.language.model.problem.Problem
+import tools.refinery.language.model.tests.ProblemTestUtil
 import tools.refinery.language.tests.ProblemInjectorProvider
-import tools.refinery.language.tests.ProblemTestUtil
 
 import static org.hamcrest.MatcherAssert.assertThat
 import static org.hamcrest.Matchers.*