IDEA-116944 Constant Conditions & Exceptions doesn't report if statements with literal true/false condition

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/DataFlowInspectionBase.java

@@ -103,6 +103,15 @@ public class DataFlowInspectionBase extends BaseJavaBatchLocalInspectionTool {
         analyzeCodeBlock(initializer.getBody(), holder, isOnTheFly);
       }
 
+      @Override
+      public void visitIfStatement(PsiIfStatement statement) {
+        PsiExpression condition = statement.getCondition();
+        if (BranchingInstruction.isBoolConst(condition)) {
+          LocalQuickFix fix = createSimplifyBooleanExpressionFix(condition, condition.textMatches(PsiKeyword.TRUE));
+          holder.registerProblem(condition, "Condition is always " + condition.getText(), fix);
+        }
+      }
+
       @Override
       public void visitAnnotation(PsiAnnotation annotation) {
         if (!ControlFlowAnalyzer.ORG_JETBRAINS_ANNOTATIONS_CONTRACT.equals(annotation.getQualifiedName())) return;

java/java-analysis-impl/src/com/intellij/codeInspection/dataFlow/instructions/BranchingInstruction.java

@@ -66,7 +66,7 @@ public abstract class BranchingInstruction extends Instruction {
     return !isConstTrue && myIsTrueReachable != myIsFalseReachable;
   }
 
-  private static boolean isBoolConst(PsiElement condition) {
+  public static boolean isBoolConst(PsiElement condition) {
     if (!(condition instanceof PsiLiteralExpression)) return false;
     @NonNls String text = condition.getText();
     return "true".equals(text) || "false".equals(text);

java/java-tests/testData/inspection/dataFlow/caseAndNpe/expected.xml

@@ -20,5 +20,10 @@
     <line>49</line>
     <description>Switch label 'case 2:' is unreachable</description>
   </problem>
+  <problem>
+    <file>CaseAndNpe.java</file>
+    <line>80</line>
+    <description>Condition is always true</description>
+  </problem>
 </problems>