From 026e917bb94c2dbd1e0cc1eba431183dcbbab88f Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Mon, 4 May 2020 21:23:10 +0200
Subject: [PATCH] java redundant cast: check for inference problems when test
 against expected by parent type (IDEA-215022)

GitOrigin-RevId: a33a36e76da7fc49284e93903158e9257b66a97c
---
 .../intellij/psi/util/RedundantCastUtil.java  |  7 ++++
 .../InferenceIncompatibilityWithoutCast.java  | 36 +++++++++++++++++++
 .../codeInspection/RedundantCast18Test.java   |  1 +
 3 files changed, 44 insertions(+)
 create mode 100644 java/java-tests/testData/inspection/redundantCast/lambda/InferenceIncompatibilityWithoutCast.java

diff --git a/java/java-analysis-impl/src/com/intellij/psi/util/RedundantCastUtil.java b/java/java-analysis-impl/src/com/intellij/psi/util/RedundantCastUtil.java
index 528af900d4dc..89c81fba339e 100644
--- a/java/java-analysis-impl/src/com/intellij/psi/util/RedundantCastUtil.java
+++ b/java/java-analysis-impl/src/com/intellij/psi/util/RedundantCastUtil.java
@@ -611,6 +611,13 @@ public class RedundantCastUtil {
           LOG.assertTrue(initializer != null, operand.getText());
           opType = initializer.getType();
 
+          if (initializer instanceof PsiMethodCallExpression) {
+            JavaResolveResult newResult = ((PsiMethodCallExpression)initializer).resolveMethodGenerics();
+            if (newResult instanceof MethodCandidateInfo && ((MethodCandidateInfo)newResult).getInferenceErrorMessage() != null) {
+              return;
+            }
+          }
+
           if (opType != null) {
             if (operand instanceof PsiConditionalExpression) {
               if (!isApplicableForConditionalBranch(opType, ((PsiConditionalExpression)operand).getThenExpression())) return;
diff --git a/java/java-tests/testData/inspection/redundantCast/lambda/InferenceIncompatibilityWithoutCast.java b/java/java-tests/testData/inspection/redundantCast/lambda/InferenceIncompatibilityWithoutCast.java
new file mode 100644
index 000000000000..2976878c00f8
--- /dev/null
+++ b/java/java-tests/testData/inspection/redundantCast/lambda/InferenceIncompatibilityWithoutCast.java
@@ -0,0 +1,36 @@
+
+import java.util.*;
+
+import java.util.function.Predicate;
+
+class MyTest<A> {
+  private final Set<A> set;
+
+  public MyTest() {
+    set = (Set<A>) newSet();
+  }
+
+  private static <A extends Comparable<A>> Set<A> newSet() {
+    return null;
+  }
+
+  static <T> Predicate<T> eq(Predicate<? super T> predicate) {
+    return predicate::test;
+  }
+
+  static <T> void test(Predicate<? super T> predicate) {
+    class X {
+      <TT> void test2() {
+        Predicate<? super TT> not = (Predicate<? super TT>)eq(predicate);
+      }
+    }
+  }
+}
+class Repro {
+  public interface MembersInjector<T> { }
+  static <T> MembersInjector<T> create(Class<T> cls) { return null; }
+  public static void main(String[] args) {
+    Class<?>[] parameterTypes = new Class<?>[1];
+    MembersInjector<Object> injector = (MembersInjector<Object>) create(parameterTypes[0]);
+  }
+}
\ No newline at end of file
diff --git a/java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast18Test.java b/java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast18Test.java
index 15a5eb4aedc3..ff0591a4272e 100644
--- a/java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast18Test.java
+++ b/java/java-tests/testSrc/com/intellij/java/codeInspection/RedundantCast18Test.java
@@ -47,4 +47,5 @@ public class RedundantCast18Test extends LightDaemonAnalyzerTestCase {
   public void testFieldInitializer() { doTest();}
   public void testDiamondWithUpperBounds() { doTest();}
   public void testBinaryConversions() { doTest();}
+  public void testInferenceIncompatibilityWithoutCast() { doTest();}
 }
\ No newline at end of file