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new c61188a [MBUILDCACHE-87] - Checksum should consider plugin
dependencies (#146)
c61188a is described below
commit c61188a4d0468d6ec0692f54faf68f08db3b6ebe
Author: Réda Housni Alaoui <reda-ala...@hey.com>
AuthorDate: Mon Jul 15 05:25:46 2024 +0200
[MBUILDCACHE-87] - Checksum should consider plugin dependencies (#146)
* Checksum should consider plugin dependencies
* Support the case of a maven plugin declared multiple times in the pom
---
.../org/apache/maven/buildcache/CacheDiff.java | 35 ++++--
.../maven/buildcache/checksum/DigestUtils.java | 4 +
.../buildcache/checksum/MavenProjectInput.java | 47 +++++++-
.../apache/maven/buildcache/xml/CacheConfig.java | 2 +
.../maven/buildcache/xml/CacheConfigImpl.java | 11 ++
src/main/mdo/build-cache-config.mdo | 11 ++
src/site/markdown/how-to.md | 13 ++
src/site/resources/maven-build-cache-config.xml | 2 +-
.../apache/maven/buildcache/its/Issue87Test.java | 133 +++++++++++++++++++++
.../.mvn/maven-build-cache-config.xml | 29 +++++
src/test/projects/mbuildcache-87/external/pom.xml | 31 +++++
.../mbuildcache-87/top/.mvn/extensions.xml | 25 ++++
.../projects/mbuildcache-87/top/module1/pom.xml | 33 +++++
.../org/apache/maven/buildcache/test.properties | 16 +++
.../projects/mbuildcache-87/top/module2/pom.xml | 72 +++++++++++
.../java/org/apache/maven/buildcache/Test2.java | 24 ++++
src/test/projects/mbuildcache-87/top/pom.xml | 47 ++++++++
17 files changed, 524 insertions(+), 11 deletions(-)
diff --git a/src/main/java/org/apache/maven/buildcache/CacheDiff.java
b/src/main/java/org/apache/maven/buildcache/CacheDiff.java
index 4c9c63b..a378804 100644
--- a/src/main/java/org/apache/maven/buildcache/CacheDiff.java
+++ b/src/main/java/org/apache/maven/buildcache/CacheDiff.java
@@ -68,6 +68,7 @@ public class CacheDiff {
compareExecutions(current.getExecutions(), baseline.getExecutions());
compareFiles(current.getProjectsInputInfo(),
baseline.getProjectsInputInfo());
compareDependencies(current.getProjectsInputInfo(),
baseline.getProjectsInputInfo());
+ comparePluginDependencies(current.getProjectsInputInfo(),
baseline.getProjectsInputInfo());
final Diff buildDiffType = new Diff();
buildDiffType.getMismatches().addAll(report);
@@ -157,20 +158,40 @@ public class CacheDiff {
}
private void compareDependencies(ProjectsInputInfo current,
ProjectsInputInfo baseline) {
- final Map<String, DigestItem> currentDependencies =
current.getItems().stream()
- .filter(item -> "dependency".equals(item.getType()))
- .collect(Collectors.toMap(DigestItem::getValue, item -> item));
+ compareDependencies(
+ "dependencies files",
+ current.getItems().stream()
+ .filter(item -> "dependency".equals(item.getType()))
+ .collect(Collectors.toList()),
+ baseline.getItems().stream()
+ .filter(item -> "dependency".equals(item.getType()))
+ .collect(Collectors.toList()));
+ }
- final Map<String, DigestItem> baselineDependencies =
baseline.getItems().stream()
- .filter(item -> "dependency".equals(item.getType()))
- .collect(Collectors.toMap(DigestItem::getValue, item -> item));
+ private void comparePluginDependencies(ProjectsInputInfo current,
ProjectsInputInfo baseline) {
+ compareDependencies(
+ "plugin dependencies files",
+ current.getItems().stream()
+ .filter(item ->
"pluginDependency".equals(item.getType()))
+ .collect(Collectors.toList()),
+ baseline.getItems().stream()
+ .filter(item ->
"pluginDependency".equals(item.getType()))
+ .collect(Collectors.toList()));
+ }
+
+ private void compareDependencies(String property, List<DigestItem>
current, List<DigestItem> baseline) {
+ final Map<String, DigestItem> currentDependencies =
+
current.stream().collect(Collectors.toMap(DigestItem::getValue, item -> item));
+
+ final Map<String, DigestItem> baselineDependencies =
+
baseline.stream().collect(Collectors.toMap(DigestItem::getValue, item -> item));
if (!Objects.equals(currentDependencies.keySet(),
baselineDependencies.keySet())) {
Set<String> currentVsBaseline = diff(currentDependencies.keySet(),
baselineDependencies.keySet());
Set<String> baselineVsCurrent =
diff(baselineDependencies.keySet(), currentDependencies.keySet());
addNewMismatch(
- "dependencies files",
+ property,
"Remote and local builds contain different sets of
dependencies and cannot be matched. "
+ "Added dependencies: " + currentVsBaseline + ".
Removed dependencies: "
+ baselineVsCurrent,
diff --git
a/src/main/java/org/apache/maven/buildcache/checksum/DigestUtils.java
b/src/main/java/org/apache/maven/buildcache/checksum/DigestUtils.java
index da0f3f2..a8e48b5 100644
--- a/src/main/java/org/apache/maven/buildcache/checksum/DigestUtils.java
+++ b/src/main/java/org/apache/maven/buildcache/checksum/DigestUtils.java
@@ -126,6 +126,10 @@ public class DigestUtils {
return item("dependency", key, checksum.update(hash));
}
+ public static DigestItem pluginDependency(HashChecksum checksum, String
key, String hash) {
+ return item("pluginDependency", key, checksum.update(hash));
+ }
+
private static String normalize(Path basedirPath, Path file) {
return FilenameUtils.separatorsToUnix(relativize(basedirPath,
file).toString());
}
diff --git
a/src/main/java/org/apache/maven/buildcache/checksum/MavenProjectInput.java
b/src/main/java/org/apache/maven/buildcache/checksum/MavenProjectInput.java
index 06ed5c4..7efc80b 100644
--- a/src/main/java/org/apache/maven/buildcache/checksum/MavenProjectInput.java
+++ b/src/main/java/org/apache/maven/buildcache/checksum/MavenProjectInput.java
@@ -35,6 +35,7 @@ import java.nio.file.attribute.BasicFileAttributes;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
+import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
@@ -45,6 +46,7 @@ import java.util.SortedMap;
import java.util.SortedSet;
import java.util.TreeMap;
import java.util.TreeSet;
+import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Predicate;
import org.apache.commons.lang3.StringUtils;
@@ -177,6 +179,7 @@ public class MavenProjectInput {
final String effectivePom =
getEffectivePom(normalizedModelProvider.normalizedModel(project));
final SortedSet<Path> inputFiles = isPom(project) ?
Collections.emptySortedSet() : getInputFiles();
final SortedMap<String, String> dependenciesChecksum =
getMutableDependencies();
+ final SortedMap<String, String> pluginDependenciesChecksum =
getMutablePluginDependencies();
final long t1 = System.currentTimeMillis();
@@ -184,7 +187,8 @@ public class MavenProjectInput {
final int count = 1
+ (config.calculateProjectVersionChecksum() ? 1 : 0)
+ inputFiles.size()
- + dependenciesChecksum.size();
+ + dependenciesChecksum.size()
+ + pluginDependenciesChecksum.size();
final List<DigestItem> items = new ArrayList<>(count);
final HashChecksum checksum =
config.getHashFactory().createChecksum(count);
@@ -237,6 +241,19 @@ public class MavenProjectInput {
LOGGER.info("Dependencies: {}", dependenciesMatched ? "MATCHED" :
"OUT OF DATE");
}
+ boolean pluginDependenciesMatched = true;
+ for (Map.Entry<String, String> entry :
pluginDependenciesChecksum.entrySet()) {
+ DigestItem dependencyDigest =
DigestUtils.pluginDependency(checksum, entry.getKey(), entry.getValue());
+ items.add(dependencyDigest);
+ if (compareWithBaseline) {
+ pluginDependenciesMatched &=
checkItemMatchesBaseline(baselineHolder.get(), dependencyDigest);
+ }
+ }
+
+ if (compareWithBaseline) {
+ LOGGER.info("Plugin dependencies: {}", pluginDependenciesMatched ?
"MATCHED" : "OUT OF DATE");
+ }
+
final ProjectsInputInfo projectsInputInfoType = new
ProjectsInputInfo();
projectsInputInfoType.setChecksum(checksum.digest());
projectsInputInfoType.getItems().addAll(items);
@@ -616,9 +633,32 @@ public class MavenProjectInput {
}
private SortedMap<String, String> getMutableDependencies() throws
IOException {
+ return getMutableDependenciesHashes("", project.getDependencies());
+ }
+
+ private SortedMap<String, String> getMutablePluginDependencies() throws
IOException {
+ Map<String, AtomicInteger> keyPrefixOccurrenceIndex = new HashMap<>();
+ SortedMap<String, String> fullMap = new TreeMap<>();
+ for (Plugin plugin : project.getBuildPlugins()) {
+ if (config.isPluginDependenciesExcluded(plugin)) {
+ continue;
+ }
+
+ String rawKeyPrefix =
KeyUtils.getVersionlessArtifactKey(repoSystem.createPluginArtifact(plugin));
+ int occurrenceIndex = keyPrefixOccurrenceIndex
+ .computeIfAbsent(rawKeyPrefix, k -> new AtomicInteger())
+ .getAndIncrement();
+ fullMap.putAll(
+ getMutableDependenciesHashes(rawKeyPrefix + "|" +
occurrenceIndex + "|", plugin.getDependencies()));
+ }
+ return fullMap;
+ }
+
+ private SortedMap<String, String> getMutableDependenciesHashes(String
keyPrefix, List<Dependency> dependencies)
+ throws IOException {
SortedMap<String, String> result = new TreeMap<>();
- for (Dependency dependency : project.getDependencies()) {
+ for (Dependency dependency : dependencies) {
if (CacheUtils.isPom(dependency)) {
// POM dependency will be resolved by maven system to actual
dependencies
@@ -648,7 +688,8 @@ public class MavenProjectInput {
projectHash = resolved.getHash();
}
result.put(
-
KeyUtils.getVersionlessArtifactKey(repoSystem.createDependencyArtifact(dependency)),
projectHash);
+ keyPrefix +
KeyUtils.getVersionlessArtifactKey(repoSystem.createDependencyArtifact(dependency)),
+ projectHash);
}
return result;
}
diff --git a/src/main/java/org/apache/maven/buildcache/xml/CacheConfig.java
b/src/main/java/org/apache/maven/buildcache/xml/CacheConfig.java
index b06d880..d86b15d 100644
--- a/src/main/java/org/apache/maven/buildcache/xml/CacheConfig.java
+++ b/src/main/java/org/apache/maven/buildcache/xml/CacheConfig.java
@@ -58,6 +58,8 @@ public interface CacheConfig {
@Nonnull
List<String> getEffectivePomExcludeProperties(Plugin plugin);
+ boolean isPluginDependenciesExcluded(Plugin plugin);
+
@Nullable
MultiModule getMultiModule();
diff --git a/src/main/java/org/apache/maven/buildcache/xml/CacheConfigImpl.java
b/src/main/java/org/apache/maven/buildcache/xml/CacheConfigImpl.java
index 69fabb7..4b6287d 100644
--- a/src/main/java/org/apache/maven/buildcache/xml/CacheConfigImpl.java
+++ b/src/main/java/org/apache/maven/buildcache/xml/CacheConfigImpl.java
@@ -304,6 +304,17 @@ public class CacheConfigImpl implements
org.apache.maven.buildcache.xml.CacheCon
return Collections.emptyList();
}
+ @Override
+ public boolean isPluginDependenciesExcluded(Plugin plugin) {
+ checkInitializedState();
+ final PluginConfigurationScan pluginConfig =
findPluginScanConfig(plugin);
+
+ if (pluginConfig != null) {
+ return pluginConfig.isExcludeDependencies();
+ }
+ return false;
+ }
+
@Nullable
@Override
public MultiModule getMultiModule() {
diff --git a/src/main/mdo/build-cache-config.mdo
b/src/main/mdo/build-cache-config.mdo
index 6271a13..ecb15e6 100644
--- a/src/main/mdo/build-cache-config.mdo
+++ b/src/main/mdo/build-cache-config.mdo
@@ -494,6 +494,12 @@ under the License.
<xs:complexType name="PluginConfigurationScanType">
<xs:complexContent>
<xs:extension base="c:CoordinatesBaseType">
+ <xs:attribute name="calculateProjectVersionChecksum"
type="xs:boolean" default="false" use="optional">
+ <xs:annotation>
+ <xs:documentation
source="version">0.0.0+</xs:documentation>
+ <xs:documentation source="description">True to exclude
plugin dependencies from the calculation rules.</xs:documentation>
+ </xs:annotation>
+ </xs:attribute>
<xs:sequence>
<xs:element name="effectivePom" minOccurs="0">
<xs:annotation>
@@ -540,6 +546,11 @@ under the License.
<name>PluginConfigurationScan</name>
<superClass>CoordinatesBase</superClass>
<fields>
+ <field xml.attribute="true">
+ <name>excludeDependencies</name>
+ <type>boolean</type>
+ <description>True to exclude plugin dependencies from the
calculation rules</description>
+ </field>
<field>
<name>effectivePom</name>
<association>
diff --git a/src/site/markdown/how-to.md b/src/site/markdown/how-to.md
index 879ccf2..e077a0a 100644
--- a/src/site/markdown/how-to.md
+++ b/src/site/markdown/how-to.md
@@ -214,3 +214,16 @@ git reset --hard
Solution: set `-Dmaven.build.cache.remote.save.final=true` to nodes that
produce final builds. Such builds will not be overridden
and eventually will replace all interim builds
+
+### I want to disable dependencies checksum calculation of one plugin
+
+Set attribute `excludeDependencies` to `true` in `input/plugins/plugin`
section:
+
+```xml
+ <input>
+ <plugins>
+ <plugin artifactId="maven-surefire-plugin" excludeDependencies="true">
+ </plugin>
+ </plugins>
+ </input>
+```
diff --git a/src/site/resources/maven-build-cache-config.xml
b/src/site/resources/maven-build-cache-config.xml
index dc965a1..b31c955 100644
--- a/src/site/resources/maven-build-cache-config.xml
+++ b/src/site/resources/maven-build-cache-config.xml
@@ -56,7 +56,7 @@
</excludes>
</global>
<plugins>
- <plugin artifactId="codegen">
+ <plugin artifactId="codegen" excludeDependencies="false">
<effectivePom>
<excludeProperties>
<excludeProperty>111</excludeProperty>
diff --git a/src/test/java/org/apache/maven/buildcache/its/Issue87Test.java
b/src/test/java/org/apache/maven/buildcache/its/Issue87Test.java
new file mode 100644
index 0000000..66e90db
--- /dev/null
+++ b/src/test/java/org/apache/maven/buildcache/its/Issue87Test.java
@@ -0,0 +1,133 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.buildcache.its;
+
+import java.io.IOException;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Arrays;
+import java.util.List;
+
+import org.apache.maven.buildcache.its.junit.IntegrationTest;
+import org.apache.maven.buildcache.util.LogFileUtils;
+import org.apache.maven.buildcache.xml.XmlService;
+import org.apache.maven.buildcache.xml.build.ProjectsInputInfo;
+import org.apache.maven.it.VerificationException;
+import org.apache.maven.it.Verifier;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+@IntegrationTest("src/test/projects/mbuildcache-87")
+public class Issue87Test {
+
+ private static final String MODULE1_PROJECT_ARTIFACT =
"org.apache.maven.caching.test.mbuildcache-87:module1:jar";
+ private static final String MODULE2_PROJECT_NAME =
"org.apache.maven.caching.test.mbuildcache-87:module2";
+ private static final String FOUND_CACHED_RESTORING_MODULE2_MESSAGE =
+ "Found cached build, restoring " + MODULE2_PROJECT_NAME + " from
cache";
+
+ @Test
+ void simple(Verifier verifier) throws VerificationException, IOException {
+ verifier.setLogFileName("../log-0.txt");
+ verifier.executeGoals(Arrays.asList("-f", "external", "install"));
+ verifier.verifyErrorFreeLog();
+
+ verifier.setAutoclean(false);
+
+ verifier.setLogFileName("../log-1.txt");
+ verifier.executeGoals(Arrays.asList("-f", "top", "verify"));
+ verifier.verifyErrorFreeLog();
+
+ verifier.setLogFileName("../log-2.txt");
+ verifier.executeGoals(Arrays.asList("-f", "top", "verify"));
+ verifier.verifyErrorFreeLog();
+ verifier.verifyTextInLog(FOUND_CACHED_RESTORING_MODULE2_MESSAGE);
+
+ // START: Modifying maven plugin reactor dependency makes the cache
stale
+
verifier.writeFile("top/module1/src/main/resources/org/apache/maven/buildcache/test.properties",
"foo=bar");
+ verifier.setLogFileName("../log-3.txt");
+ verifier.executeGoals(Arrays.asList("-f", "top", "verify"));
+ verifier.verifyErrorFreeLog();
+ verifyTextNotInLog(verifier, FOUND_CACHED_RESTORING_MODULE2_MESSAGE);
+ // END: Modifying maven plugin reactor dependency makes the cache stale
+
+ String buildInfoXmlLog =
+ LogFileUtils.findLinesContainingTextsInLogs(verifier, "Saved
Build to local file: ").stream()
+ .filter(line -> line.contains("module2"))
+ .findFirst()
+ .orElseThrow(
+ () -> new VerificationException("Could not
find module2 build info file location"));
+ Path buildInfoXmlLocation =
Paths.get(buildInfoXmlLog.split(":\\s")[1]);
+
+ ProjectsInputInfo projectsInputInfo =
+ new
XmlService().loadBuild(buildInfoXmlLocation.toFile()).getProjectsInputInfo();
+
+ assertEquals(
+ 1,
+ projectsInputInfo.getItems().stream()
+ .filter(item -> "dependency".equals(item.getType()))
+ .filter(item ->
MODULE1_PROJECT_ARTIFACT.equals(item.getValue()))
+ .count(),
+ "Expected artifact acting as plugin dependency and project
dependency to be considered twice during checksum computation");
+ assertEquals(
+ 1,
+ projectsInputInfo.getItems().stream()
+ .filter(item ->
"pluginDependency".equals(item.getType()))
+ .filter(item ->
("org.apache.maven.plugins:maven-dependency-plugin:maven-plugin|0|"
+ + MODULE1_PROJECT_ARTIFACT)
+ .equals(item.getValue()))
+ .count(),
+ "Expected artifact acting as plugin dependency and project
dependency to be considered twice during checksum computation");
+
+ assertEquals(
+ 1,
+ projectsInputInfo.getItems().stream()
+ .filter(item ->
"pluginDependency".equals(item.getType()))
+ .filter(item ->
+
"org.apache.maven.plugins:maven-dependency-plugin:maven-plugin|0|org.apache.maven.caching.test.mbuildcache-87:external:jar"
+ .equals(item.getValue()))
+ .count(),
+ "Expected external snapshot plugin dependency to be included
in the checksum computation");
+
+ assertEquals(
+ 0,
+ projectsInputInfo.getItems().stream()
+ .filter(item ->
"pluginDependency".equals(item.getType()))
+ .filter(item -> item.getValue()
+
.startsWith("org.apache.maven.plugins:maven-compiler-plugin:maven-plugin|"))
+ .count(),
+ "Expected plugins having excludeDependencies=true to have
their dependencies excluded");
+ }
+
+ private void verifyTextNotInLog(Verifier verifier, String text) throws
VerificationException {
+
+ List<String> lines = verifier.loadFile(verifier.getBasedir(),
verifier.getLogFileName(), false);
+
+ boolean result = true;
+ for (String line : lines) {
+ if (Verifier.stripAnsi(line).contains(text)) {
+ result = false;
+ break;
+ }
+ }
+ if (!result) {
+ throw new VerificationException("Text found in log: " + text);
+ }
+ }
+}
diff --git a/src/test/projects/mbuildcache-87/.mvn/maven-build-cache-config.xml
b/src/test/projects/mbuildcache-87/.mvn/maven-build-cache-config.xml
new file mode 100644
index 0000000..8e416ee
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/.mvn/maven-build-cache-config.xml
@@ -0,0 +1,29 @@
+<?xml version="1.0" encoding="UTF-8" ?>
+
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements. See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership. The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License. You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied. See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+<cache xmlns="http://maven.apache.org/BUILD-CACHE-CONFIG/1.0.0";>
+ <input>
+ <plugins>
+ <plugin groupId="org.apache.maven.plugins"
artifactId="maven-compiler-plugin" excludeDependencies="true">
+ </plugin>
+ </plugins>
+ </input>
+</cache>
diff --git a/src/test/projects/mbuildcache-87/external/pom.xml
b/src/test/projects/mbuildcache-87/external/pom.xml
new file mode 100644
index 0000000..3c0fac9
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/external/pom.xml
@@ -0,0 +1,31 @@
+<!--
+
+ Copyright 2021 the original author or authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+-->
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xmlns="http://maven.apache.org/POM/4.0.0";
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+
+ <modelVersion>4.0.0</modelVersion>
+ <groupId>org.apache.maven.caching.test.mbuildcache-87</groupId>
+ <artifactId>external</artifactId>
+ <version>0.0.1-SNAPSHOT</version>
+
+ <properties>
+ <maven.compiler.source>1.8</maven.compiler.source>
+ <maven.compiler.target>1.8</maven.compiler.target>
+ </properties>
+
+</project>
diff --git a/src/test/projects/mbuildcache-87/top/.mvn/extensions.xml
b/src/test/projects/mbuildcache-87/top/.mvn/extensions.xml
new file mode 100644
index 0000000..8df78f8
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/top/.mvn/extensions.xml
@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+ Copyright 2021 the original author or authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+-->
+<extensions>
+ <extension>
+ <groupId>org.apache.maven.extensions</groupId>
+ <artifactId>maven-build-cache-extension</artifactId>
+ <version>${projectVersion}</version>
+ </extension>
+</extensions>
diff --git a/src/test/projects/mbuildcache-87/top/module1/pom.xml
b/src/test/projects/mbuildcache-87/top/module1/pom.xml
new file mode 100644
index 0000000..b072a03
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/top/module1/pom.xml
@@ -0,0 +1,33 @@
+<!--
+
+ Copyright 2021 the original author or authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+-->
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xmlns="http://maven.apache.org/POM/4.0.0";
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+
+ <modelVersion>4.0.0</modelVersion>
+ <artifactId>module1</artifactId>
+ <packaging>jar</packaging>
+
+ <parent>
+ <groupId>org.apache.maven.caching.test.mbuildcache-87</groupId>
+ <artifactId>top</artifactId>
+ <version>0.0.1-SNAPSHOT</version>
+ <relativePath>../pom.xml</relativePath>
+ </parent>
+
+
+</project>
diff --git
a/src/test/projects/mbuildcache-87/top/module1/src/main/resources/org/apache/maven/buildcache/test.properties
b/src/test/projects/mbuildcache-87/top/module1/src/main/resources/org/apache/maven/buildcache/test.properties
new file mode 100644
index 0000000..71e666b
--- /dev/null
+++
b/src/test/projects/mbuildcache-87/top/module1/src/main/resources/org/apache/maven/buildcache/test.properties
@@ -0,0 +1,16 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied. See the License for the
+# specific language governing permissions and limitations
+# under the License.
diff --git a/src/test/projects/mbuildcache-87/top/module2/pom.xml
b/src/test/projects/mbuildcache-87/top/module2/pom.xml
new file mode 100644
index 0000000..fcc64bf
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/top/module2/pom.xml
@@ -0,0 +1,72 @@
+<!--
+
+ Copyright 2021 the original author or authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+-->
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xmlns="http://maven.apache.org/POM/4.0.0";
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+
+ <modelVersion>4.0.0</modelVersion>
+ <artifactId>module2</artifactId>
+ <packaging>jar</packaging>
+
+ <parent>
+ <groupId>org.apache.maven.caching.test.mbuildcache-87</groupId>
+ <artifactId>top</artifactId>
+ <version>0.0.1-SNAPSHOT</version>
+ <relativePath>../pom.xml</relativePath>
+ </parent>
+
+ <dependencies>
+ <dependency>
+ <groupId>${project.groupId}</groupId>
+ <artifactId>module1</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ </dependencies>
+
+ <build>
+ <plugins>
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-dependency-plugin</artifactId>
+ <dependencies>
+ <dependency>
+ <groupId>${project.groupId}</groupId>
+ <artifactId>module1</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ <dependency>
+ <groupId>${project.groupId}</groupId>
+ <artifactId>external</artifactId>
+ <version>0.0.1-SNAPSHOT</version>
+ </dependency>
+ </dependencies>
+ </plugin>
+
+ <plugin>
+ <groupId>org.apache.maven.plugins</groupId>
+ <artifactId>maven-compiler-plugin</artifactId>
+ <dependencies>
+ <dependency>
+ <groupId>${project.groupId}</groupId>
+ <artifactId>module1</artifactId>
+ <version>${project.version}</version>
+ </dependency>
+ </dependencies>
+ </plugin>
+ </plugins>
+ </build>
+</project>
diff --git
a/src/test/projects/mbuildcache-87/top/module2/src/main/java/org/apache/maven/buildcache/Test2.java
b/src/test/projects/mbuildcache-87/top/module2/src/main/java/org/apache/maven/buildcache/Test2.java
new file mode 100644
index 0000000..03f66a8
--- /dev/null
+++
b/src/test/projects/mbuildcache-87/top/module2/src/main/java/org/apache/maven/buildcache/Test2.java
@@ -0,0 +1,24 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.buildcache;
+
+class Test
+{
+
+}
\ No newline at end of file
diff --git a/src/test/projects/mbuildcache-87/top/pom.xml
b/src/test/projects/mbuildcache-87/top/pom.xml
new file mode 100644
index 0000000..1a5587f
--- /dev/null
+++ b/src/test/projects/mbuildcache-87/top/pom.xml
@@ -0,0 +1,47 @@
+<!--
+
+ Copyright 2021 the original author or authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+-->
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance";
xmlns="http://maven.apache.org/POM/4.0.0";
+ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/maven-v4_0_0.xsd";>
+
+ <modelVersion>4.0.0</modelVersion>
+ <groupId>org.apache.maven.caching.test.mbuildcache-87</groupId>
+ <artifactId>top</artifactId>
+ <version>0.0.1-SNAPSHOT</version>
+ <packaging>pom</packaging>
+
+ <properties>
+ <maven.compiler.source>1.8</maven.compiler.source>
+ <maven.compiler.target>1.8</maven.compiler.target>
+ </properties>
+
+ <build>
+ <extensions>
+ <extension>
+ <groupId>org.apache.maven.extensions</groupId>
+ <artifactId>maven-build-cache-extension</artifactId>
+ <version>${projectVersion}</version>
+ </extension>
+ </extensions>
+ </build>
+
+ <modules>
+ <module>module1</module>
+ <module>module2</module>
+ </modules>
+
+</project>
