Support Capability Coordinates in mappings

Author: jjohannes

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## Version 1.4
 * [#31](https://github.com/gradlex-org/java-module-dependencies/issues/31) DSL for module dependencies that cannot be defined in module-info
+* [#45](https://github.com/gradlex-org/java-module-dependencies/issues/45) Support Capability Coordinates in mappings
 
 ## Version 1.3.1
 

README.MD

@@ -121,12 +121,15 @@ The plugin already knows about Modules available on Maven Central. The informati
 - [modules.properties](src/main/resources/org/gradlex/javamodule/dependencies/modules.properties) - [please open a PR](https://github.com/gradlex-org/extra-java-module-info/pulls) if you miss an entry
 - [unique_modules.properties](src/main/resources/org/gradlex/javamodule/dependencies/unique_modules.properties) - this information is extracted from [modules.properties](https://github.com/sormuras/modules/blob/main/com.github.sormuras.modules/com/github/sormuras/modules/modules.properties) by [@sormuras](https://github.com/sormuras)
 
-You can define additional entries (or overwrite entries from the plugin) as follows:
+You define additional entries (or overwrite entries from the plugin) as follows:
 
 ```
-// optional configuration if required
 javaModuleDependencies {
+    // Module Name to Component GA Coordinates
     moduleNameToGA.put("org.apache.commons.lang3", "org.apache.commons:commons-lang3")
+
+    // Module Name to Component GA Coordinates & Capability GA Coordinates
+    moduleNameToGA.put("org.apache.commons.lang3.test.fixtures", "org.apache.commons:commons-lang3|org.apache.commons:commons-lang3-test-fixtures")
 }
 ```
 

src/main/java/org/gradlex/javamodule/dependencies/JavaModuleDependenciesExtension.java

@@ -71,6 +71,10 @@ public abstract class JavaModuleDependenciesExtension {
     private final ModuleInfoCache moduleInfoCache;
 
     /**
+     * Register mapping from Module Name to GA Coordinates (and optionally Capability Coordinates).
+     * - moduleNameToGA.put("org.slf4j", "org.slf4j:slf4j-api")
+     * - moduleNameToGA.put("org.slf4j.test.fixtures", "org.slf4j:slf4j-api|org.slf4j:slf4j-api-test-fixtures")
+     *
      * @return the mappings from Module Name to GA coordinates; can be modified
      */
     public abstract MapProperty<String, String> getModuleNameToGA();
@@ -156,7 +160,7 @@ public Provider<Dependency> create(String moduleName, SourceSet sourceSetWithMod
             Map<String, String> allProjectNamesAndGroups = getProject().getRootProject().getSubprojects().stream().collect(
                     Collectors.toMap(Project::getName, p -> (String) p.getGroup()));
 
-            Provider<Map<String, Object>> gav = getModuleNameToGA().getting(moduleName).orElse(mapByPrefix(getProviders().provider(() -> moduleName))).map(ga -> findGav(ga, moduleName));
+            Provider<String> coordinates = getModuleNameToGA().getting(moduleName).orElse(mapByPrefix(getProviders().provider(() -> moduleName)));
 
             ModuleInfo moduleInfo = getModuleInfoCache().get(sourceSetWithModuleInfo);
             String ownModuleNamesPrefix = moduleInfo.moduleNamePrefix(getProject().getName(), sourceSetWithModuleInfo.getName());
@@ -183,11 +187,24 @@ public Provider<Dependency> create(String moduleName, SourceSet sourceSetWithMod
                         allProjectNamesAndGroups.get(projectName) + ":" + capabilityName));
                 projectDependency.because(moduleName);
                 return projectDependency;
-            } else if (gav.isPresent()) {
-                Dependency dependency = getDependencies().create(gav.get());
+            } else if (coordinates.isPresent()) {
+                Map<String, Object> component;
+                String capability;
+                if (coordinates.get().contains("|")) {
+                    String[] split = coordinates.get().split("\\|");
+                    component = findGav(split[0], moduleName);
+                    capability = split[1];
+                } else {
+                    component = findGav(coordinates.get(), moduleName);
+                    capability = null;
+                }
+                ModuleDependency dependency = (ModuleDependency) getDependencies().create(component);
                 dependency.because(moduleName);
-                if (!gav.get().containsKey(GAV.VERSION)) {
-                    warnVersionMissing(moduleName, gav.get(), moduleInfo.getFilePath());
+                if (capability != null) {
+                    dependency.capabilities(c -> c.requireCapability(capability));
+                }
+                if (!component.containsKey(GAV.VERSION)) {
+                    warnVersionMissing(moduleName, component, moduleInfo.getFilePath());
                 }
                 return dependency;
             } else {

src/test/groovy/org/gradlex/javamodule/dependencies/test/NonMainVariantsTest.groovy

@@ -60,4 +60,29 @@ class NonMainVariantsTest extends Specification {
         then:
         result.output.contains('[lib-extra-feature.jar')
     }
+
+    def "finds published feature variant when corresponding mapping is defined"() {
+        // There are no modules published like this anywhere public right now.
+        // We test that the expected Jar file would have been downloaded if 'org.slf4j' would have test fixtures.
+        given:
+        appBuildFile << '''
+            javaModuleDependencies {
+                moduleNameToGA.put("org.slf4j.test.fixtures", "org.slf4j:slf4j-api|org.slf4j:slf4j-api-test-fixtures")
+            }
+            dependencies.constraints {
+                javaModuleDependencies { implementation(gav("org.slf4j", "2.0.3")) }
+            }
+        '''
+        appModuleInfoFile << '''
+            module org.gradlex.test.app { 
+                requires org.slf4j.test.fixtures;
+            }
+        '''
+
+        when:
+        def result = fail()
+
+        then:
+        result.output.contains('> Unable to find a variant of org.slf4j:slf4j-api:2.0.3 providing the requested capability org.slf4j:slf4j-api-test-fixtures')
+    }
 }