[java-inspection] IDEA-310567 'Constant values' false positive for switch expression

- skip 'constant values' for switch expressions if they contain always failed methods

GitOrigin-RevId: 1207911bd11f94f37293254fa609e47b42aa96e1

java/java-impl-inspections/src/com/intellij/codeInspection/dataFlow/ConstantValueInspection.java

@@ -1,4 +1,4 @@
-// Copyright 2000-2023 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
+// Copyright 2000-2024 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license.
 package com.intellij.codeInspection.dataFlow;
 
 import com.intellij.codeInsight.daemon.impl.quickfix.SimplifyBooleanExpressionFix;
@@ -400,6 +400,13 @@ public final class ConstantValueInspection extends AbstractBaseJavaLocalInspecti
         ref.set(true);
         return false;
       }
+      if (element instanceof PsiMethodCallExpression methodCallExpression) {
+        List<? extends MethodContract> contracts = JavaMethodContractUtil.getMethodCallContracts(methodCallExpression);
+        if (ContainerUtil.exists(contracts, contract -> contract.isTrivial() && contract.getReturnValue().isFail())) {
+          ref.set(true);
+          return false;
+        }
+      }
       return true;
     });
     return ref.get();

java/java-tests/testData/inspection/dataFlow/fixture/SkipSwitchExpressionWithThrow.java

@@ -1,3 +1,5 @@
+import org.jetbrains.annotations.Nullable;
+
 class SkipSwitchExpressionWithThrow {
   static boolean test(int x) {
     return switch (x) {
@@ -7,4 +9,20 @@ class SkipSwitchExpressionWithThrow {
       default -> throw new IllegalStateException();
     };
   }
+
+  public enum Foo {
+    A, B
+  }
+
+  public static <R> R exception() {
+    throw new RuntimeException();
+  }
+
+  @Nullable
+  public static Object test2(Foo foo) {
+    return switch (foo) {
+      case A -> null;
+      case B -> exception();
+    };
+  }
 }