IDEA-62171 (Intention on assert) adds "Replace If with Assert Statement" intention

plugins/IntentionPowerPak/src/META-INF/plugin.xml

@@ -367,6 +367,10 @@
       <className>com.siyeh.ipp.asserttoif.AssertToIfIntention</className>
       <categoryKey>intention.category.other</categoryKey>
     </intentionAction>
+    <intentionAction>
+      <className>com.siyeh.ipp.asserttoif.IfToAssertionIntention</className>
+      <categoryKey>intention.category.other</categoryKey>
+    </intentionAction>
     <intentionAction>
       <className>com.siyeh.ipp.enumswitch.CreateEnumSwitchBranchesIntention</className>
       <categoryKey>intention.category.other</categoryKey>

plugins/IntentionPowerPak/src/com/siyeh/IntentionPowerPackBundle.properties

@@ -134,6 +134,8 @@ replace.postfix.expression.with.assignment.intention.family.name=Replace Postfix
 replace.assignment.with.postfix.expression.intention.family.name=Replace Assignment with Postfix Expression
 convert.j.unit3.test.case.to.j.unit4.intention.family.name=Convert JUnit3 Test Case to JUnit4
 convert.j.unit3.test.case.to.j.unit4.intention.name=Convert to JUnit4 Test Case
+if.to.assertion.intention.family.name=Replace If with Assert Statement
+if.to.assertion.intention.name=Replace if with assert statement
 
 #hand made
 demorgans.intention.name1=Replace '\\&\\&' with '||'

plugins/IntentionPowerPak/src/com/siyeh/ipp/asserttoif/AssertToIfIntention.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2005 Dave Griffith
+ * Copyright 2003-2010 Dave Griffith, Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -27,28 +27,28 @@ import org.jetbrains.annotations.NotNull;
 
 public class AssertToIfIntention extends Intention {
 
+    @Override
     @NotNull
     protected PsiElementPredicate getElementPredicate() {
         return new AssertStatementPredicate();
     }
 
-    public void processIntention(PsiElement element)
+    @Override
+    public void processIntention(@NotNull PsiElement element)
             throws IncorrectOperationException {
         final PsiAssertStatement assertStatement = (PsiAssertStatement)element;
-        assert assertStatement != null;
         final PsiExpression condition = assertStatement.getAssertCondition();
         final PsiExpression description =
                 assertStatement.getAssertDescription();
-
         final String negatedConditionString =
                 BoolUtils.getNegatedExpressionText(condition);
         @NonNls final String newStatement;
         if (description == null) {
             newStatement = "if(" + negatedConditionString +
-                    "){ throw new IllegalArgumentException();}";
+                    "){ throw new java.lang.AssertionError();}";
         } else {
             newStatement = "if(" + negatedConditionString +
-                    "){ throw new IllegalArgumentException(" +
+                    "){ throw new java.lang.AssertionError(" +
                     description.getText() + ");}";
         }
         replaceStatement(newStatement, assertStatement);

plugins/IntentionPowerPak/src/com/siyeh/ipp/asserttoif/IfStatementPredicate.java

@@ -0,0 +1,78 @@
+/*
+ * Copyright 2010 Bas Leijdekkers
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.siyeh.ipp.asserttoif;
+
+import com.intellij.psi.*;
+import com.siyeh.ipp.base.PsiElementPredicate;
+
+class IfStatementPredicate implements PsiElementPredicate {
+
+    public boolean satisfiedBy(PsiElement element) {
+        if(!(element instanceof PsiJavaToken)){
+            return false;
+        }
+        final PsiJavaToken token = (PsiJavaToken)element;
+        if(token.getTokenType() != JavaTokenType.IF_KEYWORD){
+            return false;
+        }
+        final PsiElement parent = element.getParent();
+        if(!(parent instanceof PsiIfStatement)){
+            return false;
+        }
+        final PsiIfStatement statement = (PsiIfStatement) parent;
+        final PsiStatement elseBranch = statement.getElseBranch();
+        if (elseBranch != null) {
+            return false;
+        }
+        final PsiStatement thenBranch = statement.getThenBranch();
+        return isThrowNewAssertionError(thenBranch);
+    }
+
+    private static boolean isThrowNewAssertionError(PsiElement element) {
+        if (element instanceof PsiThrowStatement) {
+            final PsiThrowStatement throwStatement =
+                    (PsiThrowStatement) element;
+            final PsiExpression exception = throwStatement.getException();
+            if (!(exception instanceof PsiNewExpression)) {
+                return false;
+            }
+            final PsiNewExpression newExpression = (PsiNewExpression) exception;
+            final PsiJavaCodeReferenceElement classReference =
+                    newExpression.getClassReference();
+            if (classReference == null) {
+                return false;
+            }
+            final PsiElement target = classReference.resolve();
+            if (!(target instanceof PsiClass)) {
+                return false;
+            }
+            final PsiClass aClass = (PsiClass) target;
+            final String qualifiedName = aClass.getQualifiedName();
+            return "java.lang.AssertionError".equals(qualifiedName);
+        } else if (element instanceof PsiBlockStatement) {
+            final PsiBlockStatement blockStatement =
+                    (PsiBlockStatement) element;
+            final PsiCodeBlock codeBlock = blockStatement.getCodeBlock();
+            final PsiStatement[] statements = codeBlock.getStatements();
+            if (statements.length != 1) {
+                return false;
+            }
+            final PsiStatement statement = statements[0];
+            return isThrowNewAssertionError(statement);
+        }
+        return false;
+    }
+}

plugins/IntentionPowerPak/src/com/siyeh/ipp/asserttoif/IfToAssertionIntention.java

@@ -0,0 +1,88 @@
+/*
+ * Copyright 2010 Bas Leijdekkers
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */package com.siyeh.ipp.asserttoif;
+
+import com.intellij.psi.*;
+import com.intellij.util.IncorrectOperationException;
+import com.siyeh.ipp.base.Intention;
+import com.siyeh.ipp.base.PsiElementPredicate;
+import com.siyeh.ipp.psiutils.BoolUtils;
+import org.jetbrains.annotations.NotNull;
+
+public class IfToAssertionIntention extends Intention {
+
+    @NotNull
+    @Override
+    protected PsiElementPredicate getElementPredicate() {
+        return new IfStatementPredicate();
+    }
+
+    @Override
+    protected void processIntention(@NotNull PsiElement element)
+            throws IncorrectOperationException {
+        final PsiElement parent = element.getParent();
+        if (!(parent instanceof PsiIfStatement)) {
+            return;
+        }
+        final PsiIfStatement ifStatement = (PsiIfStatement) parent;
+
+        final PsiExpression condition = ifStatement.getCondition();
+        final String negatedExpressionText =
+                BoolUtils.getNegatedExpressionText(condition);
+        final StringBuilder newStatementText = new StringBuilder("assert ");
+        newStatementText.append(negatedExpressionText);
+        final PsiStatement thenBranch = ifStatement.getThenBranch();
+        final String message = getMessage(thenBranch);
+        if (message != null) {
+            newStatementText.append(':');
+            newStatementText.append(message);
+        }
+        newStatementText.append(';');
+        replaceStatement(newStatementText.toString(), ifStatement);
+    }
+
+    private static String getMessage(PsiElement element) {
+        if (element instanceof PsiBlockStatement) {
+            final PsiBlockStatement blockStatement = (PsiBlockStatement) element;
+            final PsiCodeBlock codeBlock = blockStatement.getCodeBlock();
+            final PsiStatement[] statements = codeBlock.getStatements();
+            if (statements.length != 1) {
+                return null;
+            }
+            final PsiStatement statement = statements[0];
+            return getMessage(statement);
+        } else if (element instanceof PsiThrowStatement) {
+            final PsiThrowStatement throwStatement = (PsiThrowStatement) element;
+
+            final PsiExpression exception = throwStatement.getException();
+            if (!(exception instanceof PsiNewExpression)) {
+                return null;
+            }
+            final PsiNewExpression newExpression = (PsiNewExpression) exception;
+            final PsiExpressionList argumentList =
+                    newExpression.getArgumentList();
+            if (argumentList == null) {
+                return null;
+            }
+            final PsiExpression[] arguments = argumentList.getExpressions();
+            if (arguments.length != 1) {
+                return null;
+            }
+            final PsiExpression argument = arguments[0];
+            return argument.getText();
+        }
+        return null;
+    }
+}

plugins/IntentionPowerPak/src/com/siyeh/ipp/switchtoif/IfToSwitchPredicate.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2003-2005 Dave Griffith
+ * Copyright 2003-2010 Dave Griffith, Bas Leijdekkers
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,10 +32,11 @@ class IfToSwitchPredicate implements PsiElementPredicate{
         if(token.getTokenType() != JavaTokenType.IF_KEYWORD){
             return false;
         }
-        if(!(element.getParent() instanceof PsiIfStatement)){
+        final PsiElement parent = element.getParent();
+        if(!(parent instanceof PsiIfStatement)){
             return false;
         }
-        final PsiIfStatement statement = (PsiIfStatement) element.getParent();
+        final PsiIfStatement statement = (PsiIfStatement) parent;
         if(ErrorUtil.containsError(statement)){
             return false;
         }

plugins/IntentionPowerPak/src/intentionDescriptions/AssertToIfIntention/after.java.template

@@ -1,7 +1,7 @@
 public class X {
   void f(Object foo) {
-     if(foo==null){
-        throw new IllegalArgumentException("Argument is null");
+     if (foo==null) {
+        throw new AssertionError("Argument is null");
      }
   }
 }

plugins/IntentionPowerPak/src/intentionDescriptions/AssertToIfIntention/before.java.template

@@ -1,5 +1,5 @@
 public class X {
   void f(Object foo) {
-    <spot>assert foo!=null: "Argument is null";</spot>
+    <spot>assert foo != null: "Argument is null";</spot>
   }
 }

plugins/IntentionPowerPak/src/intentionDescriptions/AssertToIfIntention/description.html

@@ -1,7 +1,7 @@
 <html>
 <body>
-<font face="verdana" size="-1">This intention converts a selected <b>assert</b> statement with an
-  <b>if</b> statement which throws an IllegalArgumentException if the asserted condition is false.
+<font face="verdana" size="-1">This intention replaces a selected <b>assert</b> statement with an
+  <b>if</b> statement which throws an AssertionError if the asserted condition is false.
 </font>
 </body>
 </html>

plugins/IntentionPowerPak/src/intentionDescriptions/IfToAssertionIntention/after.java.template

@@ -0,0 +1,5 @@
+public class X {
+  void f(Object foo) {
+     assert foo != null : "Argument is null";
+  }
+}

plugins/IntentionPowerPak/src/intentionDescriptions/IfToAssertionIntention/before.java.template

@@ -0,0 +1,7 @@
+public class X {
+  void f(Object foo) {
+     <spot>if</spot> (foo==null) {
+        throw new AssertionError("Argument is null");
+     }
+  }
+}

plugins/IntentionPowerPak/src/intentionDescriptions/IfToAssertionIntention/description.html

@@ -0,0 +1,7 @@
+<html>
+<body>
+<font face="verdana" size="-1">This intention replaces a selected <b>if</b> statement
+    which throws an AssertionError if the condition is false, with an <b>assert</b> statement.
+</font>
+</body>
+</html>