IPP: fix convert catch to throws inside a lambda

plugins/IntentionPowerPak/src/com/siyeh/ipp/exceptions/ConvertCatchToThrowsIntention.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2007-2012 Bas Leijdekkers
+ * Copyright 2007-2014 Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -15,6 +15,7 @@
  */
 package com.siyeh.ipp.exceptions;
 
+import com.intellij.codeInsight.FileModificationService;
 import com.intellij.openapi.project.Project;
 import com.intellij.psi.*;
 import com.intellij.psi.util.PsiTreeUtil;
@@ -36,8 +37,18 @@ public class ConvertCatchToThrowsIntention extends Intention {
   @Override
   protected void processIntention(@NotNull PsiElement element) throws IncorrectOperationException {
     final PsiCatchSection catchSection = (PsiCatchSection)element.getParent();
-    final PsiMethod method = PsiTreeUtil.getParentOfType(catchSection, PsiMethod.class);
-    if (method == null) {
+    final NavigatablePsiElement owner = PsiTreeUtil.getParentOfType(catchSection, PsiMethod.class, PsiLambdaExpression.class);
+    final PsiMethod method;
+    if (owner instanceof PsiMethod) {
+      method = (PsiMethod)owner;
+    }
+    else if (owner instanceof PsiLambdaExpression) {
+      method = LambdaUtil.getFunctionalInterfaceMethod(owner);
+      if (method == null || !FileModificationService.getInstance().preparePsiElementsForWrite(method)) {
+        return;
+      }
+    }
+    else {
       return;
     }
     // todo warn if method implements or overrides some base method

plugins/IntentionPowerPak/src/com/siyeh/ipp/exceptions/ConvertCatchToThrowsPredicate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2007-2013 Bas Leijdekkers
+ * Copyright 2007-2014 Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -29,7 +29,7 @@ class ConvertCatchToThrowsPredicate implements PsiElementPredicate {
     if (element instanceof PsiCodeBlock) {
       return false;
     }
-    final PsiMethod method = PsiTreeUtil.getParentOfType(parent, PsiMethod.class, true, PsiClass.class);
-    return method != null;
+    final PsiElement owner = PsiTreeUtil.getParentOfType(parent, PsiMethod.class, PsiClass.class, PsiLambdaExpression.class);
+    return owner instanceof PsiMethod || owner instanceof PsiLambdaExpression;
   }
 }

plugins/IntentionPowerPak/test/com/siyeh/ipp/exceptions/catchToThrows/Lambda.java

@@ -0,0 +1,19 @@
+class Lambda {
+
+  void bar() throws E {}
+
+  void foo() {
+    U u = () -> {
+      try {
+
+      } <caret>catch (E e) {
+        e.printStackTrace();
+      }
+    };
+  }
+
+  interface U {
+    void f();
+  }
+  class E extends Exception {}
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/exceptions/catchToThrows/Lambda_after.java

@@ -0,0 +1,16 @@
+class Lambda {
+
+  void bar() throws E {}
+
+  void foo() {
+    U u = () -> {
+
+
+    };
+  }
+
+  interface U {
+    void f() throws E;
+  }
+  class E extends Exception {}
+}

plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/exceptions/ConvertCatchToThrowsTest.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2000-2011 JetBrains s.r.o.
+ * Copyright 2000-2014 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -25,6 +25,7 @@ public class ConvertCatchToThrowsTest extends IPPTestCase {
   public void testArmWithPluralCatches() { doTest(); }
   public void testArmWithSingleCatch() { doTest(); }
   public void testExistingThrows() { doTest(); }
+  public void testLambda() { doTest(); }
 
   @Override
   protected String getIntentionName() {