maven-core/src/test/resources/projects/duplicate-plugins-merged-pom.xml

<project>
    <modelVersion>4.0.0</modelVersion>
    <groupId>tests.project</groupId>
    <artifactId>duplicate-plugin-defs-merged</artifactId>
    <version>1</version>

    <build>
      <plugins>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <dependencies>
            <dependency>
              <groupId>group</groupId>
              <artifactId>first</artifactId>
              <version>1</version>
            </dependency>
          </dependencies>
          <executions>
            <execution>
              <id>first</id>
              <goals>
                <goal>compile</goal>
              </goals>
            </execution>
          </executions>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <dependencies>
            <dependency>
              <groupId>group</groupId>
              <artifactId>second</artifactId>
              <version>1</version>
            </dependency>
          </dependencies>
          <executions>
            <execution>
              <id>second</id>
              <goals>
                <goal>compile</goal>
              </goals>
            </execution>
          </executions>
        </plugin>
      </plugins>
    </build>

</project>