Fix creation of generic-capabilities with multiple versions

bundles/org.eclipse.equinox.p2.publisher.eclipse/src/org/eclipse/equinox/p2/publisher/eclipse/BundlesAction.java

@@ -428,17 +428,30 @@ protected void addCapability(List<IProvidedCapability> caps, GenericDescription
 		capAttrs.compute(capNs,
 				(k, v) -> (v instanceof String) ? v : String.format("%s_%s-%s", iu.getId(), iu.getVersion(), capNo)); //$NON-NLS-1$
 
+		for (Version version : getVersions(capAttrs)) {
+			capAttrs.put(IProvidedCapability.PROPERTY_VERSION, version); // created capability contains a copy
+			caps.add(MetadataFactory.createProvidedCapability(capNs, capAttrs));
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private Collection<Version> getVersions(Map<String, Object> capAttrs) {
 		// Resolve the mandatory p2 version
 		// By convention versioned OSGi capabilities have a "version" attribute
 		// containing the OSGi Version object
 		// If this is not the case use an empty version (e.g. "osgi.ee" has a list of
 		// versions).
-		// TODO If present but not a Version log a warning somehow that it is ignored?
-		// Or fail the publication?
-		capAttrs.compute(IProvidedCapability.PROPERTY_VERSION,
-				(k, v) -> (v instanceof Version) ? v : Version.emptyVersion);
-
-		caps.add(MetadataFactory.createProvidedCapability(capNs, capAttrs));
+		Object versionValue = capAttrs.get(IProvidedCapability.PROPERTY_VERSION);
+		if (versionValue instanceof Version) {
+			return List.of((Version) versionValue);
+		}else if (versionValue instanceof Collection
+				&& ((Collection<?>) versionValue).stream().allMatch(Version.class::isInstance)) {
+			return (Collection<Version>) versionValue;
+		} else {
+			// TODO If present but not a Version log a warning somehow that it is ignored?
+			// Or fail the publication?
+			return List.of(Version.emptyVersion);
+		}
 	}
 
 	private Object convertAttribute(Object attr) {

bundles/org.eclipse.equinox.p2.tests/src/org/eclipse/equinox/p2/tests/publisher/actions/BundlesActionTest.java

@@ -33,17 +33,20 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Comparator;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
+import java.util.stream.Collectors;
 import java.util.zip.ZipInputStream;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.NullProgressMonitor;
 import org.eclipse.core.runtime.Path;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.equinox.internal.p2.director.QueryableArray;
 import org.eclipse.equinox.internal.p2.metadata.ArtifactKey;
+import org.eclipse.equinox.internal.p2.metadata.OSGiVersion;
 import org.eclipse.equinox.internal.p2.metadata.RequiredCapability;
 import org.eclipse.equinox.internal.p2.metadata.TranslationSupport;
 import org.eclipse.equinox.p2.metadata.IArtifactKey;
@@ -511,4 +514,34 @@ public void testPublishBundlesWhereOneBundleIsInvalid() throws Exception {
 				IPublisherResult.ROOT);
 		assertThat(ius.size(), is(1));
 	}
+
+	public void testMultiVersionCapability() throws Exception {
+		File testData = getTestData("dymamicImport", "testData/multiVersionCapability/bundle1");
+		IInstallableUnit iu = BundlesAction.createBundleIU(BundlesAction.createBundleDescription(testData), null,
+				new PublisherInfo());
+		Map<String, List<IProvidedCapability>> namespace2capability = iu.getProvidedCapabilities().stream()
+				.collect(Collectors.groupingBy(IProvidedCapability::getNamespace));
+
+		List<IProvidedCapability> list0 = namespace2capability.get("cap0");
+		assertCapabilities(list0, "name0", Version.emptyVersion);
+
+		List<IProvidedCapability> list1 = namespace2capability.get("cap1");
+		assertCapabilities(list1, "name1", new OSGiVersion(1, 0, 0, ""));
+
+		List<IProvidedCapability> list2 = namespace2capability.get("cap2");
+		assertCapabilities(list2, "name2", new OSGiVersion(1, 1, 0, ""));
+
+		List<IProvidedCapability> list3 = namespace2capability.get("cap3");
+		assertCapabilities(list3, "name3", new OSGiVersion(1, 0, 0, ""), new OSGiVersion(2, 1, 0, ""));
+	}
+
+	private void assertCapabilities(List<IProvidedCapability> capabilities, String expectedName,
+			Version... expectedVersions) {
+		assertEquals(expectedVersions.length, capabilities.size());
+		capabilities.forEach(c -> assertEquals(expectedName, c.getName()));
+		capabilities.sort(Comparator.comparing(IProvidedCapability::getVersion));
+		for (int i = 0; i < expectedVersions.length; i++) {
+			assertEquals(expectedVersions[i], capabilities.get(i).getVersion());
+		}
+	}
 }

bundles/org.eclipse.equinox.p2.tests/testData/multiVersionCapability/bundle1/META-INF/MANIFEST.MF

@@ -0,0 +1,9 @@
+Manifest-Version: 1.0
+Bundle-ManifestVersion: 2
+Bundle-SymbolicName: testMultiVersionCapability
+Bundle-Version: 1.0.0.qualifier
+Provide-Capability: 
+ cap0;cap0=name0;uses:="some.other",
+ cap1;cap1=name1;version:Version="1.0";uses:="some.other",
+ cap2;cap2=name2;version:List<Version>="1.1";uses:="some.other",
+ cap3;cap3=name3;version:List<Version>="1,2.1";uses:="some.other"