getDiagnostics() in BindingContext returns Diagnostics rather than List<Diagnostic>

compiler/cli/src/org/jetbrains/jet/cli/common/messages/AnalyzerWithCompilerReport.java

@@ -153,7 +153,7 @@ public final class AnalyzerWithCompilerReport {
 
     public static boolean reportDiagnostics(@NotNull BindingContext bindingContext, @NotNull MessageCollector messageCollector) {
         boolean hasErrors = false;
-        for (Diagnostic diagnostic : sortedDiagnostics(bindingContext.getDiagnostics())) {
+        for (Diagnostic diagnostic : sortedDiagnostics(bindingContext.getDiagnostics().all())) {
             hasErrors |= reportDiagnostic(diagnostic, messageCollector);
         }
         return hasErrors;

compiler/frontend/src/org/jetbrains/jet/checkers/CheckerTestUtil.java

@@ -70,7 +70,7 @@ public class CheckerTestUtil {
 
     public static List<Diagnostic> getDiagnosticsIncludingSyntaxErrors(BindingContext bindingContext, final PsiElement root) {
         ArrayList<Diagnostic> diagnostics = new ArrayList<Diagnostic>();
-        diagnostics.addAll(Collections2.filter(bindingContext.getDiagnostics(),
+        diagnostics.addAll(Collections2.filter(bindingContext.getDiagnostics().all(),
                                                new Predicate<Diagnostic>() {
                                                    @Override
                                                    public boolean apply(Diagnostic diagnostic) {

compiler/frontend/src/org/jetbrains/jet/lang/resolve/BindingContext.java

@@ -23,7 +23,6 @@ import org.jetbrains.annotations.Nullable;
 import org.jetbrains.annotations.TestOnly;
 import org.jetbrains.jet.lang.descriptors.*;
 import org.jetbrains.jet.lang.descriptors.annotations.AnnotationDescriptor;
-import org.jetbrains.jet.lang.diagnostics.Diagnostic;
 import org.jetbrains.jet.lang.psi.*;
 import org.jetbrains.jet.lang.resolve.calls.autocasts.DataFlowInfo;
 import org.jetbrains.jet.lang.resolve.calls.inference.ConstraintSystemCompleter;
@@ -46,8 +45,8 @@ public interface BindingContext {
     BindingContext EMPTY = new BindingContext() {
         @NotNull
         @Override
-        public Collection<Diagnostic> getDiagnostics() {
+        public Diagnostics getDiagnostics() {
-            return Collections.emptyList();
+            return Diagnostics.EMPTY;
         }
 
         @Override
@@ -265,7 +264,7 @@ public interface BindingContext {
             Void _static_initializer = BasicWritableSlice.initSliceDebugNames(BindingContext.class);
 
     @NotNull
-    Collection<Diagnostic> getDiagnostics();
+    Diagnostics getDiagnostics();
 
     @Nullable
     <K, V> V get(ReadOnlySlice<K, V> slice, K key);

compiler/frontend/src/org/jetbrains/jet/lang/resolve/BindingTraceContext.java

@@ -27,7 +27,8 @@ import java.util.Collection;
 import java.util.List;
 
 public class BindingTraceContext implements BindingTrace {
-    private final List<Diagnostic> diagnostics = Lists.newArrayList();
+    private final List<Diagnostic> diagnosticList = Lists.newArrayList();
+    private final Diagnostics diagnostics;
 
     // These flags are used for debugging of "Rewrite at slice..." exceptions
     /* package */ final static boolean TRACK_REWRITES = false;
@@ -39,7 +40,7 @@ public class BindingTraceContext implements BindingTrace {
 
         @NotNull
         @Override
-        public Collection<Diagnostic> getDiagnostics() {
+        public Diagnostics getDiagnostics() {
             return diagnostics;
         }
 
@@ -64,12 +65,13 @@ public class BindingTraceContext implements BindingTrace {
 
     public BindingTraceContext() {
         //noinspection ConstantConditions
-        this.map = TRACK_REWRITES ? new TrackingSlicedMap(TRACK_WITH_STACK_TRACES) : SlicedMapImpl.create();
+        this(TRACK_REWRITES ? new TrackingSlicedMap(TRACK_WITH_STACK_TRACES) : SlicedMapImpl.create());
     }
 
 
-    private BindingTraceContext(MutableSlicedMap map) {
+    private BindingTraceContext(@NotNull MutableSlicedMap map) {
         this.map = map;
+        this.diagnostics = new SimpleDiagnostics(diagnosticList);
     }
 
     @TestOnly
@@ -79,11 +81,11 @@ public class BindingTraceContext implements BindingTrace {
 
     @Override
     public void report(@NotNull Diagnostic diagnostic) {
-        diagnostics.add(diagnostic);
+        diagnosticList.add(diagnostic);
     }
 
     public void clearDiagnostics() {
-        diagnostics.clear();
+        diagnosticList.clear();
     }
 
     @Override

compiler/frontend/src/org/jetbrains/jet/lang/resolve/DelegatingBindingTrace.java

@@ -40,10 +40,10 @@ public class DelegatingBindingTrace implements BindingTrace {
     private final BindingContext bindingContext = new BindingContext() {
         @NotNull
         @Override
-        public Collection<Diagnostic> getDiagnostics() {
+        public Diagnostics getDiagnostics() {
             ArrayList<Diagnostic> mergedDiagnostics = new ArrayList<Diagnostic>(diagnostics);
-            mergedDiagnostics.addAll(parentContext.getDiagnostics());
+            mergedDiagnostics.addAll(parentContext.getDiagnostics().noSuppression().all());
-            return mergedDiagnostics;
+            return new SimpleDiagnostics(mergedDiagnostics);
         }
 
         @Override

compiler/frontend/src/org/jetbrains/jet/lang/resolve/Diagnostics.java

@@ -0,0 +1,43 @@
+package org.jetbrains.jet.lang.resolve;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.jet.lang.diagnostics.Diagnostic;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
+
+public interface Diagnostics extends Iterable<Diagnostic> {
+    @NotNull
+    Collection<Diagnostic> all();
+
+    boolean isEmpty();
+
+    @NotNull
+    Diagnostics noSuppression();
+
+    Diagnostics EMPTY = new Diagnostics() {
+        @NotNull
+        @Override
+        public Collection<Diagnostic> all() {
+            return Collections.emptyList();
+        }
+
+        @Override
+        public boolean isEmpty() {
+            return true;
+        }
+
+        @NotNull
+        @Override
+        public Diagnostics noSuppression() {
+            return this;
+        }
+
+        @NotNull
+        @Override
+        public Iterator<Diagnostic> iterator() {
+            return all().iterator();
+        }
+    };
+}

compiler/frontend/src/org/jetbrains/jet/lang/resolve/SimpleDiagnostics.java

@@ -0,0 +1,38 @@
+package org.jetbrains.jet.lang.resolve;
+
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.jet.lang.diagnostics.Diagnostic;
+
+import java.util.Collection;
+import java.util.Iterator;
+
+public class SimpleDiagnostics implements Diagnostics {
+    private final Collection<Diagnostic> diagnostics;
+
+    public SimpleDiagnostics(@NotNull Collection<Diagnostic> diagnostics) {
+        this.diagnostics = diagnostics;
+    }
+
+    @NotNull
+    @Override
+    public Collection<Diagnostic> all() {
+        return diagnostics;
+    }
+
+    @NotNull
+    @Override
+    public Diagnostics noSuppression() {
+        return this;
+    }
+
+    @NotNull
+    @Override
+    public Iterator<Diagnostic> iterator() {
+        return all().iterator();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return all().isEmpty();
+    }
+}

compiler/frontend/src/org/jetbrains/jet/lang/resolve/TraceUtil.java

@@ -64,7 +64,7 @@ public class TraceUtil {
     public final static BindingContext BINDING_CONTEXT_STUB = new BindingContext() {
         @NotNull
         @Override
-        public Collection<Diagnostic> getDiagnostics() {
+        public Diagnostics getDiagnostics() {
             throw new IllegalStateException();
         }
 

compiler/frontend/src/org/jetbrains/jet/lang/resolve/lazy/storage/LockBasedLazyResolveStorageManager.java

@@ -23,6 +23,7 @@ import org.jetbrains.annotations.TestOnly;
 import org.jetbrains.jet.lang.diagnostics.Diagnostic;
 import org.jetbrains.jet.lang.resolve.BindingContext;
 import org.jetbrains.jet.lang.resolve.BindingTrace;
+import org.jetbrains.jet.lang.resolve.Diagnostics;
 import org.jetbrains.jet.util.slicedmap.ReadOnlySlice;
 import org.jetbrains.jet.util.slicedmap.WritableSlice;
 
@@ -48,7 +49,7 @@ public class LockBasedLazyResolveStorageManager extends LockBasedStorageManager
 
         @NotNull
         @Override
-        public Collection<Diagnostic> getDiagnostics() {
+        public Diagnostics getDiagnostics() {
             synchronized (lock) {
                 return context.getDiagnostics();
             }

compiler/tests/org/jetbrains/jet/JetTestUtils.java

@@ -52,6 +52,7 @@ import org.jetbrains.jet.lang.diagnostics.Severity;
 import org.jetbrains.jet.lang.diagnostics.rendering.DefaultErrorMessages;
 import org.jetbrains.jet.lang.psi.JetFile;
 import org.jetbrains.jet.lang.psi.JetPsiFactory;
+import org.jetbrains.jet.lang.psi.JetPsiUtil;
 import org.jetbrains.jet.lang.resolve.*;
 import org.jetbrains.jet.lang.resolve.java.AnalyzerFacadeForJVM;
 import org.jetbrains.jet.lang.resolve.lazy.LazyResolveTestUtil;
@@ -101,7 +102,7 @@ public class JetTestUtils {
 
                 @NotNull
                 @Override
-                public Collection<Diagnostic> getDiagnostics() {
+                public Diagnostics getDiagnostics() {
                     throw new UnsupportedOperationException(); // TODO
                 }
 
@@ -160,7 +161,7 @@ public class JetTestUtils {
             return new BindingContext() {
                 @NotNull
                 @Override
-                public Collection<Diagnostic> getDiagnostics() {
+                public Diagnostics getDiagnostics() {
                     throw new UnsupportedOperationException();
                 }
 

idea/src/org/jetbrains/jet/plugin/highlighter/IdeRenderers.java

@@ -103,7 +103,7 @@ public class IdeRenderers {
                 private Set<ValueParameterDescriptor> getParametersToHighlight(ResolvedCall<? extends CallableDescriptor> call) {
                     Set<ValueParameterDescriptor> parameters = new HashSet<ValueParameterDescriptor>();
                     if (call instanceof ResolvedCallImpl) {
-                        Collection<Diagnostic> diagnostics = ((ResolvedCallImpl)call).getTrace().getBindingContext().getDiagnostics();
+                        Iterable<Diagnostic> diagnostics = ((ResolvedCallImpl)call).getTrace().getBindingContext().getDiagnostics();
                         for (Diagnostic diagnostic : diagnostics) {
                             if (diagnostic.getFactory() == Errors.TOO_MANY_ARGUMENTS) {
                                 parameters.add(null);

idea/src/org/jetbrains/jet/plugin/quickfix/MapPlatformClassToKotlinFix.java

@@ -78,7 +78,7 @@ public class MapPlatformClassToKotlinFix extends JetIntentionAction<JetReference
     @Override
     public void invoke(@NotNull Project project, Editor editor, JetFile file) throws IncorrectOperationException {
         BindingContext context = KotlinCacheManagerUtil.getDeclarationsBindingContext(file);
-        Collection<Diagnostic> diagnostics = context.getDiagnostics();
+        Iterable<Diagnostic> diagnostics = context.getDiagnostics();
         List<JetImportDirective> imports = new ArrayList<JetImportDirective>();
         List<JetUserType> usages = new ArrayList<JetUserType>();
 

idea/tests/org/jetbrains/jet/plugin/highlighter/DiagnosticMessageTest.java

@@ -56,7 +56,7 @@ public class DiagnosticMessageTest extends JetLiteFixture {
         BindingContext bindingContext = analyzeExhaust.getBindingContext();
 
         final Set<AbstractDiagnosticFactory> factoriesSet = Sets.newHashSet(diagnosticFactories);
-        List<Diagnostic> diagnostics = ContainerUtil.filter(bindingContext.getDiagnostics(), new Condition<Diagnostic>() {
+        List<Diagnostic> diagnostics = ContainerUtil.filter(bindingContext.getDiagnostics().all(), new Condition<Diagnostic>() {
             @Override
             public boolean value(Diagnostic diagnostic) {
                 return factoriesSet.contains(diagnostic.getFactory());

idea/tests/org/jetbrains/jet/plugin/highlighter/NoErrorsInStdlibTest.kt

@@ -47,7 +47,7 @@ public class NoErrorsInStdlibTest: LightCodeInsightFixtureTestCase() {
                 val psiFile = psiManager.findFile(file)
                 if (psiFile is JetFile) {
                     var bindingContext = AnalyzerFacadeWithCache.analyzeFileWithCache(psiFile).getBindingContext()
-                    val errors = bindingContext.getDiagnostics().filter { it.getSeverity() == Severity.ERROR }
+                    val errors = bindingContext.getDiagnostics().all().filter { it.getSeverity() == Severity.ERROR }
 
                     if (!errors.isEmpty()) {
                         System.err.println("${psiFile.getName()}: ${errors.size()} errors")

idea/tests/org/jetbrains/jet/plugin/quickfix/QuickFixActionsUtils.java

@@ -47,7 +47,7 @@ public class QuickFixActionsUtils {
 
         AnalyzeExhaust exhaust = AnalyzerFacadeWithCache.analyzeFileWithCache(file);
 
-        Collection<Diagnostic> diagnostics = exhaust.getBindingContext().getDiagnostics();
+        Collection<Diagnostic> diagnostics = exhaust.getBindingContext().getDiagnostics().all();
         Collection<Diagnostic> errorDiagnostics = Collections2.filter(diagnostics, new Predicate<Diagnostic>() {
             @Override
             public boolean apply(@Nullable Diagnostic diagnostic) {