Merge pull request #1427 from hcoles/feature/avoid_empty_method_warnings

disable filters with empty method checks for interfaces

Author: hcoles

pitest-entry/src/main/java/org/pitest/mutationtest/build/intercept/equivalent/EqualsPerformanceShortcutFilter.java

@@ -61,6 +61,13 @@ public void begin(ClassTree clazz) {
   @Override
   public Collection<MutationDetails> intercept(
       Collection<MutationDetails> mutations, Mutater m) {
+
+    // skip for mutations to annotations on interfaces
+    // to avoid generating empty method warnings.
+    if (this.currentClass.isInterface()) {
+      return mutations;
+    }
+
    final List<MutationDetails> doNotTouch = mutations.stream()
            .filter(inEqualsMethod().negate())
            .collect(Collectors.toList());

pitest-entry/src/main/java/org/pitest/mutationtest/build/intercept/javafeatures/ForEachLoopFilter.java

@@ -184,6 +184,13 @@ public void begin(ClassTree clazz) {
   @Override
   public Collection<MutationDetails> intercept(
       Collection<MutationDetails> mutations, Mutater m) {
+
+    // skip for mutations to annotations on interfaces
+    // to avoid generating empty method warnings.
+    if (this.currentClass.isInterface()) {
+      return mutations;
+    }
+
     return mutations.stream().filter(mutatesIteratorLoopPlumbing().negate())
             .collect(Collectors.toList());
   }

pitest-entry/src/main/java/org/pitest/mutationtest/build/intercept/timeout/AvoidForLoopCounterFilter.java

@@ -49,7 +49,7 @@
 import org.pitest.util.Log;
 
 /**
- * Removes mutants that affect for loop counters as these have
+ * Removes mutants that effect for loop counters as these have
  * a high chance of timing out.
  */
 public class AvoidForLoopCounterFilter implements MutationInterceptor {
@@ -152,6 +152,13 @@ public void begin(ClassTree clazz) {
   @Override
   public Collection<MutationDetails> intercept(
       Collection<MutationDetails> mutations, Mutater m) {
+
+    // skip for mutations to annotations on interfaces
+    // to avoid generating empty method warnings.
+    if (this.currentClass.isInterface()) {
+      return mutations;
+    }
+
     return mutations.stream()
             .filter(mutatesAForLoopCounter().negate())
             .collect(Collectors.toList());

pitest-entry/src/main/java/org/pitest/mutationtest/build/intercept/timeout/InfiniteLoopFilter.java

@@ -43,6 +43,13 @@ public void begin(ClassTree clazz) {
   @Override
   public Collection<MutationDetails> intercept(
       Collection<MutationDetails> mutations, Mutater m) {
+
+    // skip for mutations to annotations on interfaces
+    // to avoid generating empty method warnings.
+    if (this.currentClass.isInterface()) {
+      return mutations;
+    }
+
     final Map<Location,Collection<MutationDetails>> buckets = FCollection.bucket(mutations, mutationToLocation());
 
     final List<MutationDetails> willTimeout = new ArrayList<>();