Fix plugin ordering. Exclude branches from travis

.travis.yml

@@ -4,6 +4,10 @@ jdk:
 cache:
   directories:
   - $HOME/.m2
+branches:
+  only:
+    - master
+    - /^release-.+$/
 script: >
   mvn test \
    -Dteavm.test.skip=false \

core/src/main/java/org/teavm/vm/TeaVM.java

@@ -766,7 +766,7 @@ public class TeaVM implements TeaVMHost, ServiceRepository {
      * obtains all implementation classes that are enumerated there.</p>
      */
     public void installPlugins() {
-        for (TeaVMPlugin plugin : ServiceLoader.load(TeaVMPlugin.class, classLoader)) {
+        for (TeaVMPlugin plugin : TeaVMPluginLoader.load(classLoader)) {
             plugin.install(this);
         }
     }

core/src/main/java/org/teavm/vm/TeaVMPluginLoader.java

@@ -73,7 +73,7 @@ public final class TeaVMPluginLoader {
                 .collect(Collectors.toList());
     }
 
-    public static List<String> orderPlugins(ClassLoader classLoader, Set<String> classNames) {
+    static List<String> orderPlugins(ClassLoader classLoader, Set<String> classNames) {
         Map<String, PluginDescriptor> descriptors = new HashMap<>();
         try {
             for (String className : classNames) {
@@ -160,11 +160,11 @@ public final class TeaVMPluginLoader {
                 throw new IllegalStateException("Plugin " + descriptor.name
                         + " has both before and after annotations");
             }
-            descriptor.beforeList.addAll(Arrays.asList(descriptor.before));
+            descriptor.afterList.addAll(Arrays.asList(descriptor.after));
-            for (String after : descriptor.after) {
+            for (String before : descriptor.before) {
-                PluginDescriptor afterDescriptor = descriptors.get(after);
+                PluginDescriptor beforeDescriptor = descriptors.get(before);
-                if (afterDescriptor != null && afterDescriptor.reachable) {
+                if (beforeDescriptor != null && beforeDescriptor.reachable) {
-                    afterDescriptor.beforeList.add(descriptor.name);
+                    beforeDescriptor.afterList.add(descriptor.name);
                 }
             }
         }
@@ -180,14 +180,15 @@ public final class TeaVMPluginLoader {
         }
         path.add(descriptor.name);
 
-        for (String before : descriptor.beforeList) {
+        for (String after : descriptor.afterList) {
-            PluginDescriptor beforeDescriptor = descriptors.get(before);
+            PluginDescriptor afterDescriptor = descriptors.get(after);
-            if (beforeDescriptor != null) {
+            if (afterDescriptor != null && afterDescriptor.reachable) {
-                if (visited.contains(before) && !emmited.contains(before)) {
+                if (visited.contains(after) && !emmited.contains(after)) {
                     List<String> loop = new ArrayList<>();
+                    Collections.reverse(path);
                     for (String pathElem : path) {
                         loop.add(pathElem);
-                        if (pathElem.equals(descriptor.name)) {
+                        if (pathElem.equals(afterDescriptor.name)) {
                             break;
                         }
                     }
@@ -195,7 +196,7 @@ public final class TeaVMPluginLoader {
                     throw new IllegalStateException("Circular dependency found: " + loop.stream()
                             .collect(Collectors.joining(" -> ")));
                 }
-                orderDescriptors(beforeDescriptor, descriptors, list, visited, emmited, path);
+                orderDescriptors(afterDescriptor, descriptors, list, visited, emmited, path);
             }
         }
 
@@ -260,7 +261,7 @@ public final class TeaVMPluginLoader {
         String[] requires = new String[0];
         String[] before = new String[0];
         String[] after = new String[0];
-        List<String> beforeList = new ArrayList<>();
+        List<String> afterList = new ArrayList<>();
         boolean reachable;
     }
 }

core/src/test/java/org/teavm/vm/PluginLoaderTest.java

@@ -15,12 +15,13 @@
  */
 package org.teavm.vm;
 
-import static org.hamcrest.CoreMatchers.*;
+import static org.hamcrest.CoreMatchers.is;
-import static org.junit.Assert.*;
+import static org.junit.Assert.assertThat;
 import java.util.Arrays;
 import java.util.List;
 import java.util.stream.Collectors;
 import org.junit.Test;
+import org.teavm.vm.spi.After;
 import org.teavm.vm.spi.Before;
 import org.teavm.vm.spi.Requires;
 import org.teavm.vm.spi.TeaVMHost;
@@ -37,6 +38,25 @@ public class PluginLoaderTest {
         assertThat(plugins.size(), is(2));
         assertThat(plugins.get(0), is(B.class.getName()));
         assertThat(plugins.get(1), is(A.class.getName()));
+
+        plugins = order(C.class, D.class);
+        assertThat(plugins.size(), is(2));
+        assertThat(plugins.get(0), is(C.class.getName()));
+        assertThat(plugins.get(1), is(D.class.getName()));
+    }
+
+    @Test
+    public void respectsPluginDependency() {
+        List<String> plugins = order(B.class);
+        assertThat(plugins.size(), is(0));
+
+        plugins = order(A.class);
+        assertThat(plugins.size(), is(1));
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void detectsCircularDependency() {
+        order(Pre.class, Head.class, Tail.class);
     }
 
     private List<String> order(Class<?>... classes) {
@@ -57,4 +77,39 @@ public class PluginLoaderTest {
         public void install(TeaVMHost host) {
         }
     }
+
+    static class C implements TeaVMPlugin {
+        @Override
+        public void install(TeaVMHost host) {
+        }
+    }
+
+    @After(C.class)
+    @Requires(C.class)
+    static class D implements TeaVMPlugin {
+        @Override
+        public void install(TeaVMHost host) {
+        }
+    }
+
+    @Before(Head.class)
+    static class Pre implements TeaVMPlugin {
+        @Override
+        public void install(TeaVMHost host) {
+        }
+    }
+
+    @Before(Tail.class)
+    static class Head implements TeaVMPlugin {
+        @Override
+        public void install(TeaVMHost host) {
+        }
+    }
+
+    @Before(Head.class)
+    static class Tail implements TeaVMPlugin {
+        @Override
+        public void install(TeaVMHost host) {
+        }
+    }
 }

pom.xml

@@ -243,7 +243,7 @@
         <plugin>
           <groupId>org.apache.maven.plugins</groupId>
           <artifactId>maven-checkstyle-plugin</artifactId>
-          <version>2.15</version>
+          <version>2.16</version>
           <executions>
             <execution>
               <id>validate</id>