eclipse / transformer

The documentation for the Maven plugin says:

When using this goal without specifying a classifier, the plugin must be configured with <extensions>true</extensions> in order to coordinate with the maven-jar-plugin.

However, there is no such property documented, and indeed it does not work:

[WARNING] Parameter 'extensions' is unknown for plugin 'transformer-maven-plugin:0.5.0:jar (default)'
[ERROR] Failed to execute goal org.eclipse.transformer:transformer-maven-plugin:0.5.0:jar (default) on project test: In order to use the transformer-maven-plugin packaging goal jar without a classifier, <extensions>true</extensions> must be set on the plugin configuration

It is not part of the plugin's configuration but it is part of the pom to add the plugin as a build extension. See https://maven.apache.org/guides/mini/guide-using-extensions.html#build-extension.

For example, see:

transformer/maven-plugins/transformer-maven-plugin/src/it/simple-jar/pom.xml

Lines 55 to 64 in 49a7892

    
           <plugin> 
        
           	<groupId>org.eclipse.transformer</groupId> 
        
           	<artifactId>transformer-maven-plugin</artifactId> 
        
           	<version>${transformer.version}</version> 
        
           	<extensions>true</extensions> 
        
           	<configuration> 
        
           		<rules> 
        
           			<jakartaDefaults>true</jakartaDefaults> 
        
           		</rules> 
        
           	</configuration>

	<plugin>
	<groupId>org.eclipse.transformer</groupId>
	<artifactId>transformer-maven-plugin</artifactId>
	<version>${transformer.version}</version>
	<extensions>true</extensions>
	<configuration>
	<rules>
	<jakartaDefaults>true</jakartaDefaults>
	</rules>
	</configuration>