* [Sealed types][Switch] Pattern switch - ECJ accepts code rejected b…

…y javac(#3060) * Unchecked casts go unreported with ECJ * Fixes #1802 * Fixes #1735
eclipse-jdt · Oct 10, 2024 · 09766de · 09766de
1 parent 02fda8d
commit 09766de
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Showing 3 changed files with 105 additions and 19 deletions.
diff --git a/...pse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CastExpression.java b/...pse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/ast/CastExpression.java
@@ -430,24 +430,21 @@ public static boolean checkUnsafeCast(Expression expression, Scope scope, TypeBi
  ParameterizedTypeBinding paramCastType = (ParameterizedTypeBinding) castType;
  TypeBinding[] castArguments = paramCastType.arguments;
  int length = castArguments == null ? 0 : castArguments.length;
- if ((paramCastType.tagBits & (TagBits.HasDirectWildcard|TagBits.HasTypeVariable)) != 0) {
- // verify alternate cast type, substituting different type arguments
- for (int i = 0; i < length; i++) {
- if (castArguments[i].isUnboundWildcard())
- continue;
- TypeBinding[] alternateArguments;
- // need to clone for each iteration to avoid env paramtype cache interference
- System.arraycopy(paramCastType.arguments, 0, alternateArguments = new TypeBinding[length], 0, length);
- alternateArguments[i] = TypeBinding.equalsEquals(paramCastType.arguments[i], scope.getJavaLangObject()) ? scope.getJavaLangBoolean() : scope.getJavaLangObject();
- LookupEnvironment environment = scope.environment();
- ParameterizedTypeBinding alternateCastType = environment.createParameterizedType((ReferenceBinding)castType.erasure(), alternateArguments, castType.enclosingType());
- if (TypeBinding.equalsEquals(alternateCastType.findSuperTypeOriginatingFrom(expressionType), match)) {
- expression.bits |= ASTNode.UnsafeCast;
- break;
- }
+ // verify alternate cast type, substituting different type arguments
+ for (int i = 0; i < length; i++) {
+ if (castArguments[i].isUnboundWildcard())
+ continue;
+ TypeBinding[] alternateArguments;
+ // need to clone for each iteration to avoid env paramtype cache interference
+ System.arraycopy(paramCastType.arguments, 0, alternateArguments = new TypeBinding[length], 0, length);
+ alternateArguments[i] = TypeBinding.equalsEquals(paramCastType.arguments[i], scope.getJavaLangObject()) ? scope.getJavaLangBoolean() : scope.getJavaLangObject();
+ LookupEnvironment environment = scope.environment();
+ ParameterizedTypeBinding alternateCastType = environment.createParameterizedType((ReferenceBinding)castType.erasure(), alternateArguments, castType.enclosingType());
+ if (TypeBinding.equalsEquals(alternateCastType.findSuperTypeOriginatingFrom(expressionType), match)) {
+ expression.bits |= ASTNode.UnsafeCast;
+ break;
  }
  }
-
  // Type arguments added by subtypes of S and removed by supertypes of T don't need to be checked since the type arguments aren't specified by either S or T
  return true;
  } else {

diff --git a/...s.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest.java b/...s.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/GenericsRegressionTest.java
@@ -6975,5 +6975,47 @@ public void testBugGH656_2() {
  "The method JavacWillAlsoError.someAbstractMethod() does not override the inherited method from MyAbstract since it is private to a different package\n" +
  "----------\n");
 }
+// https://github.com/eclipse-jdt/eclipse.jdt.core/issues/1802
+// Unchecked casts go unreported with ECJ
+public void testIssue1802() {
+ Runner runner = new Runner();
+ runner.testFiles =
+ new String[] {
+ "X.java",
+ """
+ class X {
+ void foo(I<X> ix) {
+ A<Y> ay = (A<Y>) ix;
+ B<X> bx = (B<X>) ix;
+ }
+ }
+ class Y extends X {}
+ class Z extends X {}
+
+ interface I<T> {
+ }
+
+ final class B<T> implements I<X> {
+ }
+
+
+ final class A<T> implements I<X> {
+ }
+ """
+ };
+ runner.expectedCompilerLog =
+ "----------\n" +
+ "1. WARNING in X.java (at line 3)\n" +
+ " A<Y> ay = (A<Y>) ix;\n" +
+ " ^^^^^^^^^\n" +
+ "Type safety: Unchecked cast from I<X> to A<Y>\n" +
+ "----------\n" +
+ "2. WARNING in X.java (at line 4)\n" +
+ " B<X> bx = (B<X>) ix;\n" +
+ " ^^^^^^^^^\n" +
+ "Type safety: Unchecked cast from I<X> to B<X>\n" +
+ "----------\n";
+ runner.runWarningTest();
+}
 }
 
diff --git a/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java b/....tests.compiler/src/org/eclipse/jdt/core/tests/compiler/regression/SwitchPatternTest.java
@@ -8541,8 +8541,8 @@ public static void main(String[] args) {
  "42\n420\n4200");
  }
 
- public void testIssue3009_4() { // FIXME: this should not compile!!!
- runConformTest(
+ public void testIssue3009_4() {
+ runNegativeTest(
  new String[] {
  "X.java",
  """
@@ -8572,7 +8572,12 @@ public static void main(String[] args) {
  }
  """
  },
- "42\n420\n4200");
+ "----------\n" +
+ "1. ERROR in X.java (at line 13)\r\n" +
+ " case H<Integer, X> e -> 4200;\r\n" +
+ " ^^^^^^^^^^^^^^^\n" +
+ "Type J<Integer,X> cannot be safely cast to H<Integer,X>\n" +
+ "----------\n");
  }
 
  public void testIssue3009_5() {
@@ -8817,4 +8822,46 @@ public static void main(String[] args) {
  },
  "42\n420");
  }
+
+ // https://github.com/eclipse-jdt/eclipse.jdt.core/issues/1735
+ // [Sealed types][Switch] Pattern switch - ECJ accepts code rejected by javac
+ public void testIssue1735() {
+ runNegativeTest(
+ new String[] {
+ "X.java",
+ """
+ class X {
+ void foo(I<X> ix) {
+ switch(ix) {
+ case A<Y> ay -> System.out.println();
+ case B<X> bx -> System.out.println();
+ }
+ }
+ }
+ class Y extends X {}
+ class Z extends X {}
+
+ sealed interface I<T> permits A, B {
+ }
+
+ final class B<T> implements I<X> {
+ }
+
+
+ final class A<T> implements I<X> {
+ }
+ """
+ },
+ "----------\n" +
+ "1. ERROR in X.java (at line 4)\n" +
+ " case A<Y> ay -> System.out.println();\n" +
+ " ^^^^^^^\n" +
+ "Type I<X> cannot be safely cast to A<Y>\n" +
+ "----------\n" +
+ "2. ERROR in X.java (at line 5)\n" +
+ " case B<X> bx -> System.out.println();\n" +
+ " ^^^^^^^\n" +
+ "Type I<X> cannot be safely cast to B<X>\n" +
+ "----------\n");
+ }
 }