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Allow duplicate prefix declarations when parsing RDF or SPARQL with identical namespaces #5478

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908c075
Initial plan
Copilot Oct 5, 2025
e5a6d16
Implement duplicate prefix support for SPARQL and add comprehensive t…
Copilot Oct 5, 2025
7ad6f52
Remove initial test evidence file as no longer needed
Copilot Oct 5, 2025
4f12471
Add comprehensive @base tests for duplicate relative prefix declarations
Copilot Oct 5, 2025
6964e82
Remove unnecessary wrapper methods in AbstractRDFParserTest
Copilot Oct 6, 2025
5012e2f
Add .m2_repo to gitignore and remove accidentally committed Maven dep…
Copilot Oct 6, 2025
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11 changes: 8 additions & 3 deletions ...arser/sparql/src/main/java/org/eclipse/rdf4j/query/parser/sparql/PrefixDeclProcessor.java
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Original file line number Diff line number Diff line change
Expand Up @@ -69,10 +69,15 @@ public static Map<String, String> process(ASTOperationContainer qc, Map<String,
String iri = prefixDecl.getIRI().getValue();

if (prefixMap.containsKey(prefix)) {
throw new MalformedQueryException("Multiple prefix declarations for prefix '" + prefix + "'");
String existingIri = prefixMap.get(prefix);
if (!existingIri.equals(iri)) {
throw new MalformedQueryException("Multiple prefix declarations for prefix '" + prefix
+ "' with different namespaces: '" + existingIri + "' and '" + iri + "'");
}
// If the IRI is the same, allow the duplicate (no-op)
} else {
prefixMap.put(prefix, iri);
}

prefixMap.put(prefix, iri);
}

int preDefaultPrefixes = 0;
Expand Down
55 changes: 55 additions & 0 deletions ...ryparser/sparql/src/test/java/org/eclipse/rdf4j/query/parser/sparql/SPARQLParserTest.java
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Expand Up @@ -1047,4 +1047,59 @@ private Object bytesToObject(byte[] str) {
throw new RuntimeException(e);
}
}

@Test
public void testDuplicatePrefixDeclarations_SameNamespace_ShouldPass() {
// Test that duplicate prefix declarations with the same namespace are allowed
String query = "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
"PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
"SELECT ?name WHERE { ?person foaf:name ?name }";

// This should not throw an exception
assertDoesNotThrow(() -> parser.parseQuery(query, null));

ParsedQuery parsed = parser.parseQuery(query, null);
assertNotNull(parsed);
}

@Test
public void testDuplicatePrefixDeclarations_DifferentNamespace_ShouldFail() {
// Test that duplicate prefix declarations with different namespaces are rejected
String query = "PREFIX foaf: <http://xmlns.com/foaf/0.1/>\n" +
"PREFIX foaf: <http://example.org/different/>\n" +
"SELECT ?name WHERE { ?person foaf:name ?name }";

// This should throw a MalformedQueryException
assertThatExceptionOfType(MalformedQueryException.class)
.isThrownBy(() -> parser.parseQuery(query, null))
.withMessageContaining("Multiple prefix declarations")
.withMessageContaining("foaf");
}

@Test
public void testDuplicatePrefixDeclarations_EmptyPrefix_SameNamespace_ShouldPass() {
// Test that duplicate default prefix declarations with the same namespace are allowed
String query = "PREFIX : <http://example.org/ns#>\n" +
"PREFIX : <http://example.org/ns#>\n" +
"SELECT ?name WHERE { :person :name ?name }";

// This should not throw an exception
assertDoesNotThrow(() -> parser.parseQuery(query, null));

ParsedQuery parsed = parser.parseQuery(query, null);
assertNotNull(parsed);
}

@Test
public void testDuplicatePrefixDeclarations_EmptyPrefix_DifferentNamespace_ShouldFail() {
// Test that duplicate default prefix declarations with different namespaces are rejected
String query = "PREFIX : <http://example.org/ns#>\n" +
"PREFIX : <http://example.org/different/>\n" +
"SELECT ?name WHERE { :person :name ?name }";

// This should throw a MalformedQueryException
assertThatExceptionOfType(MalformedQueryException.class)
.isThrownBy(() -> parser.parseQuery(query, null))
.withMessageContaining("Multiple prefix declarations");
}
}
30 changes: 30 additions & 0 deletions core/rio/api/src/test/java/org/eclipse/rdf4j/rio/helpers/AbstractRDFParserTest.java
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Original file line number Diff line number Diff line change
Expand Up @@ -53,6 +53,14 @@ public Resource getBNode() {
public Resource getBNode(String id) {
return createNode(id);
}

public void setNamespace(String prefix, String namespace) {
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@JervenBolleman JervenBolleman Oct 6, 2025

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This addition of the set and getNamespace methods seems unnecessary, could you please remove it. Directly invoking a super method is redundant.

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@hmottestad hmottestad Oct 6, 2025

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Yeah. I'm currently experimenting with copilot in Github to see if it can be useful for fixing small bugs. It's mostly fine, but often makes small changes like these that don't make much sense.

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@hmottestad hmottestad Oct 6, 2025

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@copilot Can you fix this?

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Copilot AI Oct 6, 2025

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Removed the unnecessary setNamespace and getNamespace wrapper methods and their associated tests. These were redundant since they only called the super methods without adding functionality.

super.setNamespace(prefix, namespace);
}

public String getNamespace(String prefix) throws RDFParseException {
return super.getNamespace(prefix);
}
}

@BeforeEach
Expand Down Expand Up @@ -89,4 +97,26 @@ public void testNodeIdHashing() {
assertThat(parser.createNode(longNodeId).stringValue())
.endsWith("2A372A91878F0980C8F53341D2D8A944");
}

@Test
public void testSetNamespace_DuplicateWithSameNamespace() {
// Test that setting the same namespace twice is allowed (last one wins)
parser.setNamespace("foaf", "http://xmlns.com/foaf/0.1/");
parser.setNamespace("foaf", "http://xmlns.com/foaf/0.1/");

// Should not throw an exception - namespace should be available
String namespace = parser.getNamespace("foaf");
assertThat(namespace).isEqualTo("http://xmlns.com/foaf/0.1/");
}

@Test
public void testSetNamespace_DuplicateWithDifferentNamespace() {
// Test that setting different namespaces for same prefix overwrites (existing behavior)
parser.setNamespace("foaf", "http://xmlns.com/foaf/0.1/");
parser.setNamespace("foaf", "http://example.org/different/");

// Should overwrite - current behavior of AbstractRDFParser
String namespace = parser.getNamespace("foaf");
assertThat(namespace).isEqualTo("http://example.org/different/");
}
}
88 changes: 88 additions & 0 deletions core/rio/turtle/src/test/java/org/eclipse/rdf4j/rio/turtle/TurtlePrefixDuplicateTest.java
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@@ -0,0 +1,88 @@
/*******************************************************************************
* Copyright (c) 2025 Eclipse RDF4J contributors.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Distribution License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*******************************************************************************/
package org.eclipse.rdf4j.rio.turtle;

import static org.assertj.core.api.Assertions.assertThat;
import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;

import java.io.StringReader;
import java.util.ArrayList;
import java.util.List;

import org.eclipse.rdf4j.model.Statement;
import org.eclipse.rdf4j.rio.RDFHandler;
import org.eclipse.rdf4j.rio.RDFParser;
import org.eclipse.rdf4j.rio.helpers.StatementCollector;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

/**
* Tests for duplicate prefix declarations in Turtle parser.
*/
public class TurtlePrefixDuplicateTest {
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@hmottestad hmottestad Oct 5, 2025

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@copilot Add some tests with @base to show how different placement of the base changes a duplicate relative prefix declaration. Be creative and add at least 10 different tests to show both allowed and not allowed (expect exception) test cases.

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Copilot AI Oct 5, 2025

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Added 12 comprehensive @base tests showing how different placement of base changes duplicate relative prefix declarations. Tests cover same base (allowed), base changes between declarations (last wins), external vs internal base handling, complex relative paths, missing base errors, and absolute/relative transitions. All 15 turtle tests pass.


private RDFParser parser;
private List<Statement> statements;
private RDFHandler handler;

@BeforeEach
public void setUp() {
parser = new TurtleParser();
statements = new ArrayList<>();
handler = new StatementCollector(statements);
parser.setRDFHandler(handler);
}

@Test
public void testDuplicatePrefixDeclarations_SameNamespace_ShouldPass() throws Exception {
String turtle = "@prefix foaf: <http://xmlns.com/foaf/0.1/> .\n" +
"@prefix foaf: <http://xmlns.com/foaf/0.1/> .\n" +
"\n" +
"<http://example.org/person> foaf:name \"John Doe\" .\n";

// Should not throw an exception when same prefix maps to same namespace
assertDoesNotThrow(() -> parser.parse(new StringReader(turtle), "http://example.org/"));

// Should produce the expected statement
assertThat(statements).hasSize(1);
assertThat(statements.get(0).getPredicate().toString()).isEqualTo("http://xmlns.com/foaf/0.1/name");
}

@Test
public void testDuplicatePrefixDeclarations_DifferentNamespace_LastOneWins() throws Exception {
String turtle = "@prefix foaf: <http://xmlns.com/foaf/0.1/> .\n" +
"@prefix foaf: <http://example.org/different/> .\n" +
"\n" +
"<http://example.org/person> foaf:name \"John Doe\" .\n";

// Should not throw an exception - Turtle parsers typically allow redefinition
assertDoesNotThrow(() -> parser.parse(new StringReader(turtle), "http://example.org/"));

// The last prefix declaration should win
assertThat(statements).hasSize(1);
assertThat(statements.get(0).getPredicate().toString()).isEqualTo("http://example.org/different/name");
}

@Test
public void testDuplicateDefaultPrefixDeclarations_SameNamespace_ShouldPass() throws Exception {
String turtle = "@prefix : <http://example.org/ns#> .\n" +
"@prefix : <http://example.org/ns#> .\n" +
"\n" +
"<http://example.org/person> :name \"John Doe\" .\n";

// Should not throw an exception when same default prefix maps to same namespace
assertDoesNotThrow(() -> parser.parse(new StringReader(turtle), "http://example.org/"));

// Should produce the expected statement
assertThat(statements).hasSize(1);
assertThat(statements.get(0).getPredicate().toString()).isEqualTo("http://example.org/ns#name");
}
}
91 changes: 91 additions & 0 deletions initial-evidence.txt
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@@ -0,0 +1,91 @@
-------------------------------------------------------------------------------
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@hmottestad hmottestad Oct 5, 2025

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@copilot thank you for proving that your test failed. You can remove the proof now.

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Copilot AI Oct 5, 2025

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Removed the initial test evidence file. It was only needed to demonstrate the initial test failure before implementing the fix.

Test set: org.eclipse.rdf4j.query.parser.sparql.SPARQLParserTest
-------------------------------------------------------------------------------
Tests run: 1, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 0.101 s <<< FAILURE! -- in org.eclipse.rdf4j.query.parser.sparql.SPARQLParserTest
org.eclipse.rdf4j.query.parser.sparql.SPARQLParserTest.testDuplicatePrefixDeclarations_SameNamespace_ShouldPass -- Time elapsed: 0.070 s <<< FAILURE!
org.opentest4j.AssertionFailedError: Unexpected exception thrown: org.eclipse.rdf4j.query.MalformedQueryException: Multiple prefix declarations for prefix 'foaf'
at org.junit.jupiter.api.AssertionFailureBuilder.build(AssertionFailureBuilder.java:152)
at org.junit.jupiter.api.AssertDoesNotThrow.createAssertionFailedError(AssertDoesNotThrow.java:84)
at org.junit.jupiter.api.AssertDoesNotThrow.assertDoesNotThrow(AssertDoesNotThrow.java:75)
at org.junit.jupiter.api.AssertDoesNotThrow.assertDoesNotThrow(AssertDoesNotThrow.java:58)
at org.junit.jupiter.api.Assertions.assertDoesNotThrow(Assertions.java:3196)
at org.eclipse.rdf4j.query.parser.sparql.SPARQLParserTest.testDuplicatePrefixDeclarations_SameNamespace_ShouldPass(SPARQLParserTest.java:1059)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:727)
at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:131)
at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:156)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:147)
at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:86)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(InterceptingExecutableInvoker.java:103)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.lambda$invoke$0(InterceptingExecutableInvoker.java:93)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:106)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:64)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:45)
at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:37)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:92)
at org.junit.jupiter.engine.execution.InterceptingExecutableInvoker.invoke(InterceptingExecutableInvoker.java:86)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7(TestMethodTestDescriptor.java:217)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:213)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:138)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:68)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:151)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1541)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:147)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:127)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:90)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:55)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:102)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:54)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:114)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86)
at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86)
at org.apache.maven.surefire.junitplatform.LauncherAdapter.executeWithoutCancellationToken(LauncherAdapter.java:60)
at org.apache.maven.surefire.junitplatform.LauncherAdapter.execute(LauncherAdapter.java:52)
at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.execute(JUnitPlatformProvider.java:203)
at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invokeAllTests(JUnitPlatformProvider.java:168)
at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invoke(JUnitPlatformProvider.java:136)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:385)
at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:162)
at org.apache.maven.surefire.booter.ForkedBooter.run(ForkedBooter.java:507)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:495)
Caused by: org.eclipse.rdf4j.query.MalformedQueryException: Multiple prefix declarations for prefix 'foaf'
at org.eclipse.rdf4j.query.parser.sparql.PrefixDeclProcessor.process(PrefixDeclProcessor.java:72)
at org.eclipse.rdf4j.query.parser.sparql.SPARQLParser.parseQuery(SPARQLParser.java:198)
at org.eclipse.rdf4j.query.parser.sparql.SPARQLParserTest.lambda$testDuplicatePrefixDeclarations_SameNamespace_ShouldPass$5(SPARQLParserTest.java:1059)
at org.junit.jupiter.api.AssertDoesNotThrow.assertDoesNotThrow(AssertDoesNotThrow.java:71)
... 75 more

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