Why can't generate source features?

Question

project structure:

project structure

category.xml

<?xml version="1.0" encoding="UTF-8"?>
<site>
 <feature id="com.test.A.feature" version="0.0.0">
 <category name="com.test.A.repository"/>
 </feature>
 <feature id="com.test.A.feature.source" version="0.0.0">
 <category name="com.test.A.repository"/>
 </feature>
 <category-def name="com.test.A.repository" label="Test A"/>
</site>

pom.xml

<?xml version="1.0"?>
<project
 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"
 xmlns="http://maven.apache.org/POM/4.0.0"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
 <modelVersion>4.0.0</modelVersion>
 <groupId>com.test</groupId>
 <artifactId>build</artifactId>
 <version>0.0.1-SNAPSHOT</version>
 <packaging>pom</packaging>
 <properties>
 <tycho.version>4.0.10</tycho.version>
 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 </properties>
 <modules>
 <module>com.test.A</module>
 <module>com.test.A.feature</module>
 <module>com.test.A.repository</module>
 </modules>
 <build>
 <plugins>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-maven-plugin</artifactId>
 <extensions>true</extensions>
 </plugin>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-packaging-plugin</artifactId>
 <configuration>
 <format>yyyyMMdd-HHmm</format>
 </configuration>
 </plugin>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-source-plugin</artifactId>
 <executions>
 <execution>
 <id>plugin-source</id>
 <goals>
 <goal>plugin-source</goal>
 </goals>
 </execution>
 <execution>
 <id>feature-source</id>
 <goals>
 <goal>feature-source</goal>
 </goals>
 </execution>
 </executions>
 </plugin>
 </plugins>
 <pluginManagement>
 <plugins>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-maven-plugin</artifactId>
 <version>${tycho.version}</version>
 </plugin>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-packaging-plugin</artifactId>
 <version>${tycho.version}</version>
 </plugin>
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-source-plugin</artifactId>
 <version>${tycho.version}</version>
 </plugin>
 </plugins>
 </pluginManagement>
 </build>
</project>

build:

mvn clean verify

error:

[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] build 0.0.1-SNAPSHOT ............................... SUCCESS [ 0.126 s]
[INFO] [bundle] A 1.0.0-SNAPSHOT .......................... SUCCESS [ 2.514 s]
[INFO] [feature] A Feature 1.0.0-SNAPSHOT ................. SUCCESS [ 0.507 s]
[INFO] [updatesite] com.test.A.repository.eclipse-repository 0.0.1-SNAPSHOT FAILURE [ 0.079 s]
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 10.819 s
[INFO] Finished at: 2024年11月27日T19:44:00+08:00
[INFO] ------------------------------------------------------------------------
[ERROR] Cannot resolve dependencies of project com.test:com.test.A.repository.eclipse-repository:eclipse-repository:0.0.1-SNAPSHOT
[ERROR] with context {osgi.os=win32, osgi.ws=win32, org.eclipse.update.install.features=true, osgi.arch=x86_64, org.eclipse.update.install.sources=true}
[ERROR] Software being installed: com.test.A.repository.eclipse-repository raw:0.0.1.'SNAPSHOT'/format(n[.n=0;[.n=0;[-S]]]):0.0.1-SNAPSHOT
[ERROR] Missing requirement: com.test.A.repository.eclipse-repository raw:0.0.1.'SNAPSHOT'/format(n[.n=0;[.n=0;[-S]]]):0.0.1-SNAPSHOT requires 'org.eclipse.equinox.p2.iu; com.test.A.feature.source.feature.group 0.0.0' but it could not be found: See log for details
[ERROR] -> [Help 1]

Why isn't A source feature automatically generated?

I referenced these articles:

tycho-source-plugin

11.5. Building source features

Tycho 12: Build source features

there seems to be no relevant omissions. Am I missing something? Thanks.

Solution:

need tycho-p2-plugin:p2-metadata

...
 <plugin>
 <groupId>org.eclipse.tycho</groupId>
 <artifactId>tycho-p2-plugin</artifactId>
 <executions>
 <execution>
 <id>p2-metadata</id>
 <goals>
 <goal>p2-metadata</goal>
 </goals>
 <phase>package</phase>
 </execution>
 </executions>
 </plugin>
...

While the problem is solved, I still don't know what it actually did, does anyone know? Thanks.