"jar" assembly format produces unexpected MANIFEST files and ignores "index" attribute with different archive settings

Basically, the problem is that assembly plugin generates unexpected MANIFEST.MF file and ignores "index" attributes when using "jar" format.

Assumption

Expected result is based on assumption that plugin should produce the same result as default jar plugin does when using the same archive settings (they both backed by the maven archiver). Attached archive contains test project that generates three jars using the "maven-jar-plugin" and three other jars using the "maven-assembly-plugin". Both plugins has the same archive settings.

Test Data

Basic assembly plugin configuration:

	
<plugin>
	<groupId>org.apache.maven.plugins</groupId>
	<artifactId>maven-assembly-plugin</artifactId>
	<version>2.4</version>

	<!-- Shared basic configuration -->
	<configuration>
		<appendAssemblyId>false</appendAssemblyId>
		<attach>false</attach>
		<descriptorId>jar-with-dependencies</descriptorId>
		<format>jar</format>
		<archive>
			<!-- Do not put POM descriptor -->
			<addMavenDescriptor>false</addMavenDescriptor>
			<!-- Generate INDEX.LIST file -->
			<index>true</index>
		</archive>
	</configuration>
	...
</plugin>

src/main/assembly/META-INF/MANIFEST.MF:

Manifest-Version: 1.0
DisplayName: Test Display Name

Test #1

Execution that generates jar using default archiver MANIFEST file:

<execution>
	<id>assembly-with-default-manifest</id>
	<phase>package</phase>
	<goals>
		<goal>single</goal>
	</goals>
	<configuration>
		<finalName>${project.build.finalName}-assembly-default-manifest</finalName>
	</configuration>
</execution>

Expected result:

INDEX.LIST file is present and contains:

JarIndex-Version: 1.0

manifest-test-0.1-assembly-default-manifest.jar
ru
ru/javatalks
ru/javatalks/tests

MANIFEST.MF file is present and contains:

Manifest-Version: 1.0
Built-By: gesser
Build-Jdk: 1.6.0_45
Created-By: Apache Maven 3.0.5
Archiver-Version: Plexus Archiver

Actual Result:

INDEX.LIST file is missing.

MANIFEST.MF file exists and contains expected entries.

Test #2

Execution that generates jar using custom MANIFEST file:

<execution>
	<id>assembly-with-custom-manifest</id>
	<phase>package</phase>
	<goals>
		<goal>single</goal>
	</goals>
	<configuration>
		<finalName>${project.build.finalName}-assembly-custom-manifest</finalName>
		<archive>
			<manifestFile>src/main/assembly/META-INF/MANIFEST.MF</manifestFile>
		</archive>
	</configuration>
</execution>

Expected Result:

INDEX.LIST file is present and contains:

JarIndex-Version: 1.0

manifest-test-0.1-assembly-custom-manifest.jar
ru
ru/javatalks
ru/javatalks/tests

MANIFEST.MF file is present and contains:

Manifest-Version: 1.0
Built-By: gesser
Build-Jdk: 1.6.0_45
Created-By: Apache Maven 3.0.5
DisplayName: Test Display Name
Archiver-Version: Plexus Archiver

Actual Result:

INDEX.LIST file is missing.

MANIFEST.MF file exists, but contains unexpected entries:

Manifest-Version: 1.0
Created-By: 20.45-b01 (Sun Microsystems Inc.)
DisplayName: Test Display Name
Archiver-Version: Plexus Archiver

Test #3

Execution that generates jar using custom MANIFEST file plus custom entries:

<execution>
	<id>assembly-with-custom-manifest-and-entries</id>
	<phase>package</phase>
	<goals>
		<goal>single</goal>
	</goals>
	<configuration>
		<finalName>${project.build.finalName}-assembly-custom-manifest-and-entries</finalName>
		<archive>
			<manifestFile>src/main/assembly/META-INF/MANIFEST.MF</manifestFile>
			<manifestEntries>
				<Built-date>${maven.build.timestamp}</Built-date>
				<Version>${project.version}</Version>
			</manifestEntries>
		</archive>
	</configuration>
</execution>

Expected Result:

INDEX.LIST file is present and contains:

JarIndex-Version: 1.0

manifest-test-0.1-assembly-custom-manifest-and-entries.jar
ru
ru/javatalks
ru/javatalks/tests

MANIFEST.MF file is present and contains:

Manifest-Version: 1.0
Built-By: gesser
Build-Jdk: 1.6.0_45
Created-By: Apache Maven 3.0.5
Built-date: 20130623-2318
DisplayName: Test Display Name
Version: 0.1
Archiver-Version: Plexus Archiver

Actual Result:

INDEX.LIST file is missing.

MANIFEST.MF file exists, but contains unexpected entries:

Manifest-Version: 1.0
Created-By: 20.45-b01 (Sun Microsystems Inc.)
DisplayName: Test Display Name
Archiver-Version: Plexus Archiver

Additional information:

Maven version: 3.0.5
Java version: 1.6.0_45