[java-inspections] RedundantCompareCall: insert cast when both operands are boxed

Fixes IDEA-291826 IntelliJ Suggest simplify Integer.compare method to `==`

GitOrigin-RevId: 71882cec49e2846f0b30ae626da6d07381e516e2

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/redundantCompareCall/afterBoxing.java

@@ -0,0 +1,10 @@
+// "Fix all 'Redundant 'compare()' method call' problems in file" "true"
+class Boxing {
+  void test(Integer x, Integer y, int z) {
+    boolean same = (int) x == y;
+    boolean same1 = x > y;
+    boolean same2 = (int) x != y;
+    boolean same3 = x == z;
+    boolean same4 = z == x;
+  }
+}

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/quickFix/redundantCompareCall/beforeBoxing.java

@@ -0,0 +1,10 @@
+// "Fix all 'Redundant 'compare()' method call' problems in file" "true"
+class Boxing {
+  void test(Integer x, Integer y, int z) {
+    boolean same = Integer.<caret>compare(x, y) == 0;
+    boolean same1 = Integer.compare(x, y) > 0;
+    boolean same2 = Integer.compare(x, y) != 0;
+    boolean same3 = Integer.compare(x, z) == 0;
+    boolean same4 = Integer.compare(z, x) == 0;
+  }
+}

plugins/InspectionGadgets/src/com/intellij/codeInspection/RedundantCompareCallInspection.java

@@ -70,10 +70,21 @@ public class RedundantCompareCallInspection extends AbstractBaseJavaLocalInspect
       if (call == null) return;
       PsiExpression[] args = call.getArgumentList().getExpressions();
       if(args.length != 2) return;
+      String maybeCast = "";
+      if (myRelationType == RelationType.EQ || myRelationType == RelationType.NE) {
+        PsiType leftType = args[0].getType();
+        PsiType rightType = args[1].getType();
+        if (leftType instanceof PsiClassType && rightType instanceof PsiClassType) {
+          PsiPrimitiveType type = PsiPrimitiveType.getOptionallyUnboxedType(leftType);
+          if (type != null) {
+            maybeCast = "(" + type.getCanonicalText() + ")";
+          }
+        }
+      }
       PsiBinaryExpression parent = PsiTreeUtil.getParentOfType(call, PsiBinaryExpression.class);
       if (parent == null) return;
       CommentTracker ct = new CommentTracker();
-      ct.replaceAndRestoreComments(parent, ct.text(args[0], ParenthesesUtils.EQUALITY_PRECEDENCE) +
+      ct.replaceAndRestoreComments(parent, maybeCast + ct.text(args[0], ParenthesesUtils.EQUALITY_PRECEDENCE) +
                                            myRelationType +
                                            ct.text(args[1], ParenthesesUtils.EQUALITY_PRECEDENCE));
     }