IDEA-63698 (Inconvertible type (assign double to Integer) not highlighted as error)

java/java-analysis-impl/src/com/intellij/codeInsight/daemon/impl/analysis/HighlightUtil.java

@@ -361,7 +361,6 @@ public class HighlightUtil extends HighlightUtilBase {
 
   @Nullable
   static HighlightInfo checkAssignmentCompatibleTypes(@NotNull PsiAssignmentExpression assignment) {
-    if (!"=".equals(assignment.getOperationSign().getText())) return null;
     PsiExpression lExpr = assignment.getLExpression();
     PsiExpression rExpr = assignment.getRExpression();
     if (rExpr == null) return null;
@@ -369,16 +368,27 @@ public class HighlightUtil extends HighlightUtilBase {
     PsiType rType = rExpr.getType();
     if (rType == null) return null;
 
-    HighlightInfo highlightInfo = checkAssignability(lType, rType, rExpr, assignment);
+    final IElementType sign = assignment.getOperationTokenType();
+    HighlightInfo highlightInfo;
+    if (JavaTokenType.EQ.equals(sign)) {
+      highlightInfo = checkAssignability(lType, rType, rExpr, assignment);
+    }
+    else {
+      // 15.26.2. Compound Assignment Operators
+      final IElementType opSign = TypeConversionUtil.convertEQtoOperation(sign);
+      final PsiType type = TypeConversionUtil.calcTypeForBinaryExpression(lType, rType, opSign, true);
+      if (type == null || lType == null || TypeConversionUtil.areTypesConvertible(type, lType)) {
+        return null;
+      }
+      highlightInfo = createIncompatibleTypeHighlightInfo(lType, type, assignment.getTextRange(), 0);
+    }
     if (highlightInfo == null) {
       return null;
     }
-
     registerChangeVariableTypeFixes(lExpr, rType, highlightInfo);
     if (lType != null) {
       registerChangeVariableTypeFixes(rExpr, lType, highlightInfo);
     }
-
     return highlightInfo;
   }
 

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting/AssignmentCompatible.java

@@ -42,5 +42,9 @@ public class a  {
     int i1='d';
     <error descr="Incompatible types. Found: 'long', required: 'int'">int i2 = 1L;</error>
 
+    Integer destination = 25;
+    <error descr="Incompatible types. Found: 'double', required: 'java.lang.Integer'">destination += 2.0</error>;
+    Byte b = 1;
+    <error descr="Incompatible types. Found: 'int', required: 'java.lang.Byte'">b -= 1</error>;
   }
 }

java/java-tests/testSrc/com/intellij/codeInsight/daemon/LightAdvHighlightingTest.java

@@ -119,7 +119,7 @@ public class LightAdvHighlightingTest extends LightDaemonAnalyzerTestCase {
   public void testAssignToFinal() { doTest(false, false); }
   public void testUnhandledExceptionsInSuperclass() { doTest(false, false); }
   public void testNoUnhandledExceptionsMultipleInheritance() { doTest(false, false); }
-  public void testAssignmentCompatible () { doTest(false, false); }
+  public void testAssignmentCompatible () { setLanguageLevel(LanguageLevel.JDK_1_5); doTest(false, false); }
   public void testMustBeBoolean() { doTest(false, false); }
 
   public void testNumericLiterals() { doTest(false, false); }