convert to nested ifs: treat nested or-/parenthesis- expr simple; include return statements on top level and expr only (IDEA-126049)

plugins/IntentionPowerPak/src/com/siyeh/ipp/trivialif/ConvertToNestedIfIntention.java

@@ -62,7 +62,7 @@ public class ConvertToNestedIfIntention extends Intention {
     if (returnValue == null || ErrorUtil.containsDeepError(returnValue)) {
       return;
     }
-    final String newStatementText = buildIf(returnValue, new StringBuilder()).toString();
+    final String newStatementText = buildIf(returnValue, true, new StringBuilder()).toString();
     final Project project = returnStatement.getProject();
     final PsiElementFactory elementFactory = JavaPsiFacade.getInstance(project).getElementFactory();
     final PsiBlockStatement blockStatement = (PsiBlockStatement)elementFactory.createStatementFromText("{" + newStatementText + "}", returnStatement);
@@ -73,23 +73,23 @@ public class ConvertToNestedIfIntention extends Intention {
     PsiReplacementUtil.replaceStatement(returnStatement, "return false;");
   }
 
-  private static StringBuilder buildIf(@Nullable PsiExpression expression, StringBuilder out) {
+  private static StringBuilder buildIf(@Nullable PsiExpression expression, boolean top, StringBuilder out) {
     if (expression instanceof PsiPolyadicExpression) {
       final PsiPolyadicExpression polyadicExpression = (PsiPolyadicExpression)expression;
       final PsiExpression[] operands = polyadicExpression.getOperands();
       final IElementType tokenType = polyadicExpression.getOperationTokenType();
       if (JavaTokenType.ANDAND.equals(tokenType)) {
         for (PsiExpression operand : operands) {
-          buildIf(operand, out);
+          buildIf(operand, false, out);
         }
-        if (!StringUtil.endsWith(out, "return true;")) {
+        if (top && !StringUtil.endsWith(out, "return true;")) {
           out.append("return true;");
         }
         return out;
       }
-      else if (JavaTokenType.OROR.equals(tokenType)) {
+      else if (top && JavaTokenType.OROR.equals(tokenType)) {
         for (PsiExpression operand : operands) {
-          buildIf(operand, out);
+          buildIf(operand, false, out);
           if (!StringUtil.endsWith(out, "return true;")) {
             out.append("return true;");
           }
@@ -99,7 +99,7 @@ public class ConvertToNestedIfIntention extends Intention {
     }
     else if (expression instanceof PsiParenthesizedExpression) {
       final PsiParenthesizedExpression parenthesizedExpression = (PsiParenthesizedExpression)expression;
-      buildIf(parenthesizedExpression.getExpression(), out);
+      buildIf(parenthesizedExpression.getExpression(), top, out);
       return out;
     }
     if (expression != null) {

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/OrStaircaseInside.java

@@ -0,0 +1,7 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  boolean f(boolean a, boolean b, boolean c, boolean d) {
+    return a |<caret>| (b && c) || d;
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/OrStaircaseInside_after.java

@@ -0,0 +1,10 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  boolean f(boolean a, boolean b, boolean c, boolean d) {
+      if (a) return true;
+      if (b) if (c) return true;
+      if (d) return true;
+      return false;
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/StaircaseWithOrInside.java

@@ -0,0 +1,7 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  boolean f(boolean a, boolean b, boolean c, boolean d) {
+    return a &<caret>& (b || c) && d;
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/StaircaseWithOrInside_after.java

@@ -0,0 +1,8 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  boolean f(boolean a, boolean b, boolean c, boolean d) {
+      if (a) if (b || c) if (d) return true;
+      return false;
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/StaircaseWithParenthesis.java

@@ -0,0 +1,19 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  public static boolean foo(double a, double b, double c)
+  {
+    // the following return statement is converted by "Convert to multiple 'ifs'" (on the second &&) to the below, incorrect if-then-else
+    return (a > c && a < b) &<caret>& !bar1(a) && !bar2(a);
+  }
+
+  private static boolean bar1(double a)
+  {
+    return true;
+  }
+
+  private static boolean bar2(double a)
+  {
+    return true;
+  }
+}

plugins/IntentionPowerPak/test/com/siyeh/ipp/trivialif/convert_to_nested_if/StaircaseWithParenthesis_after.java

@@ -0,0 +1,20 @@
+package com.siyeh.ipp.trivialif.convert_to_nested_if;
+
+public class X {
+  public static boolean foo(double a, double b, double c)
+  {
+    // the following return statement is converted by "Convert to multiple 'ifs'" (on the second &&) to the below, incorrect if-then-else
+      if (a > c) if (a < b) if (!bar1(a)) if (!bar2(a)) return true;
+      return false;
+  }
+
+  private static boolean bar1(double a)
+  {
+    return true;
+  }
+
+  private static boolean bar2(double a)
+  {
+    return true;
+  }
+}

plugins/IntentionPowerPak/testSrc/com/siyeh/ipp/trivialif/ConvertToNestedIfIntentionTest.java

@@ -22,6 +22,9 @@ public class ConvertToNestedIfIntentionTest extends IPPTestCase {
 
   public void testNested() { doTest(); }
   public void testStaircase() { doTest(); }
+  public void testStaircaseWithParenthesis() { doTest(); }
+  public void testStaircaseWithOrInside() { doTest(); }
+  public void testOrStaircaseInside() { doTest(); }
   public void testOneLevelStaircase() { assertIntentionNotAvailable(); }
 
   public void testAndOrMixed() { doTest(); }