Do not fail on circular dependencies + better message

jps-plugin/src/org/jetbrains/jet/jps/build/KotlinBuilder.java

@@ -16,6 +16,8 @@
 
 package org.jetbrains.jet.jps.build;
 
+import com.intellij.openapi.util.text.StringUtil;
+import com.intellij.util.Function;
 import com.intellij.util.containers.ContainerUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.jet.cli.common.messages.CompilerMessageLocation;
@@ -29,19 +31,27 @@ import org.jetbrains.jps.builders.java.JavaSourceRootDescriptor;
 import org.jetbrains.jps.incremental.*;
 import org.jetbrains.jps.incremental.messages.BuildMessage;
 import org.jetbrains.jps.incremental.messages.CompilerMessage;
+import org.jetbrains.jps.model.module.JpsModule;
 
 import java.io.File;
 import java.io.IOException;
 import java.util.Collection;
 import java.util.List;
 
-import static org.jetbrains.jet.cli.common.messages.CompilerMessageSeverity.ERROR;
 import static org.jetbrains.jet.cli.common.messages.CompilerMessageSeverity.EXCEPTION;
+import static org.jetbrains.jet.cli.common.messages.CompilerMessageSeverity.WARNING;
 
 public class KotlinBuilder extends ModuleLevelBuilder {
 
     private static final String KOTLIN_BUILDER_NAME = "Kotlin Builder";
 
+    private static final Function<JpsModule,String> MODULE_NAME = new Function<JpsModule, String>() {
+        @Override
+        public String fun(JpsModule module) {
+            return module.getName();
+        }
+    };
+
     protected KotlinBuilder() {
         super(BuilderCategory.SOURCE_PROCESSOR);
     }
@@ -63,10 +73,14 @@ public class KotlinBuilder extends ModuleLevelBuilder {
         MessageCollector messageCollector = new MessageCollectorAdapter(context);
 
         if (chunk.getModules().size() > 1) {
+            // We do not support circular dependencies, but if they are present, we should not break the build,
+            // so we simply yield a warning and report NOTHING_DONE
             messageCollector.report(
-                    ERROR, "Circular dependencies are not supported: " + chunk.getModules(),
+                    WARNING, "Circular dependencies are not supported. " +
+                             "The following modules depend on each other: " + StringUtil.join(chunk.getModules(), MODULE_NAME, ", ") + ". " +
+                             "Kotlin is not compiled for these modules",
                     CompilerMessageLocation.NO_LOCATION);
-            return ExitCode.ABORT;
+            return ExitCode.NOTHING_DONE;
         }
 
         ModuleBuildTarget representativeTarget = chunk.representativeTarget();

jps-plugin/test/org/jetbrains/jet/jps/build/KotlinJpsBuildTestCase.java

@@ -82,6 +82,10 @@ public class KotlinJpsBuildTestCase extends AbstractKotlinJpsBuildTestCase {
         doTestWithRuntime();
     }
 
+    public void testCircularDependenciesNoKotlinFiles() {
+        doTest();
+    }
+
     public void testTestDependencyLibrary() throws Throwable {
         initProject();
         addKotlinRuntimeDependency(JpsJavaDependencyScope.TEST);

jps-plugin/testData/CircularDependenciesNoKotlinFiles/kotlinProject.iml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="jdk" jdkName="IDEA_JDK" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="library" name="KotlinRuntime" level="project" />
+    <orderEntry type="module" module-name="module2" />
+  </component>
+</module>
+

jps-plugin/testData/CircularDependenciesNoKotlinFiles/kotlinProject.ipr

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <option name="DEFAULT_COMPILER" value="Javac" />
+  </component>
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/kotlinProject.iml" filepath="$PROJECT_DIR$/kotlinProject.iml" />
+      <module fileurl="file://$PROJECT_DIR$/module2/module2.iml" filepath="$PROJECT_DIR$/module2/module2.iml" />
+    </modules>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_6" assert-keyword="true" jdk-15="true" project-jdk-name="IDEA_JDK" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>

jps-plugin/testData/CircularDependenciesNoKotlinFiles/module2/module2.iml

@@ -0,0 +1,14 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="jdk" jdkName="IDEA_JDK" jdkType="JavaSDK" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="module" module-name="kotlinProject" />
+    <orderEntry type="library" name="KotlinRuntime" level="project" />
+  </component>
+</module>
+

jps-plugin/testData/CircularDependenciesNoKotlinFiles/module2/src/JSecond.java

@@ -0,0 +1,5 @@
+public class JSecond {
+    public static void main(String[] args) {
+        new JFirst().foo();
+    }
+}

jps-plugin/testData/CircularDependenciesNoKotlinFiles/src/JFirst.java

@@ -0,0 +1,11 @@
+public class JFirst {
+    JSecond s = null;
+
+    public void foo() {
+
+    }
+
+    public static void main(String[] args) {
+        System.out.println(1);
+    }
+}