[FIR] Prohibit referencing java field in case of conflict with proper…

…ty..

..from companion object of the derived class

^KT-68056 Fixed

compiler/fir/checkers/checkers.jvm/src/org/jetbrains/kotlin/fir/analysis/jvm/checkers/expression/FirFieldAccessShadowedByInvisibleKotlinProperty.kt

@@ -12,20 +12,23 @@ import org.jetbrains.kotlin.fir.analysis.checkers.MppCheckerKind
 import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
 import org.jetbrains.kotlin.fir.analysis.checkers.expression.FirCallableReferenceAccessChecker
 import org.jetbrains.kotlin.fir.analysis.checkers.expression.FirPropertyAccessExpressionChecker
+import org.jetbrains.kotlin.fir.analysis.checkers.unsubstitutedScope
 import org.jetbrains.kotlin.fir.analysis.diagnostics.jvm.FirJvmErrors.JAVA_FIELD_SHADOWED_BY_KOTLIN_PROPERTY
+import org.jetbrains.kotlin.fir.declarations.FirFile
 import org.jetbrains.kotlin.fir.declarations.isJavaOrEnhancement
 import org.jetbrains.kotlin.fir.declarations.utils.hasBackingField
-import org.jetbrains.kotlin.fir.expressions.FirCallableReferenceAccess
-import org.jetbrains.kotlin.fir.expressions.FirPropertyAccessExpression
-import org.jetbrains.kotlin.fir.expressions.FirQualifiedAccessExpression
-import org.jetbrains.kotlin.fir.expressions.toResolvedCallableSymbol
+import org.jetbrains.kotlin.fir.expressions.*
 import org.jetbrains.kotlin.fir.isVisible
 import org.jetbrains.kotlin.fir.resolve.scope
 import org.jetbrains.kotlin.fir.scopes.CallableCopyTypeCalculator
 import org.jetbrains.kotlin.fir.scopes.getProperties
+import org.jetbrains.kotlin.fir.symbols.impl.FirClassSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirFieldSymbol
 import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
+import org.jetbrains.kotlin.fir.symbols.impl.FirRegularClassSymbol
 import org.jetbrains.kotlin.fir.types.resolvedType
+import org.jetbrains.kotlin.fir.types.toClassSymbol
+import org.jetbrains.kotlin.fir.types.toRegularClassSymbol
 import org.jetbrains.kotlin.fir.visibilityChecker
 
 object FirFieldAccessShadowedByInvisibleKotlinProperty : FirPropertyAccessExpressionChecker(MppCheckerKind.Platform) {
@@ -51,14 +54,25 @@ private fun checkFieldAccess(
 
     val containingFile = context.containingFile ?: return
     val dispatchReceiver = expression.dispatchReceiver ?: return
-    val dispatchReceiverScope = dispatchReceiver.resolvedType.scope(
+    checkClashWithInvisibleProperty(context, fieldSymbol, containingFile, dispatchReceiver, reporter, expression)
+    checkClashWithCompanionProperty(context, fieldSymbol, reporter, expression)
+}
+
+private fun checkClashWithInvisibleProperty(
+    context: CheckerContext,
+    fieldSymbol: FirFieldSymbol,
+    containingFile: FirFile,
+    dispatchReceiver: FirExpression,
+    reporter: DiagnosticReporter,
+    expression: FirQualifiedAccessExpression,
+) {
+    val scope = dispatchReceiver.resolvedType.scope(
         context.session,
         context.scopeSession,
         CallableCopyTypeCalculator.Forced,
         requiredMembersPhase = null
     ) ?: return
-
-    val properties = dispatchReceiverScope.getProperties(fieldSymbol.name)
+    val properties = scope.getProperties(fieldSymbol.name)
     for (property in properties) {
         if (property !is FirPropertySymbol) continue
         if (!property.hasBackingField) continue
@@ -75,3 +89,22 @@ private fun checkFieldAccess(
         }
     }
 }
+
+private fun checkClashWithCompanionProperty(
+    context: CheckerContext,
+    fieldSymbol: FirFieldSymbol,
+    reporter: DiagnosticReporter,
+    expression: FirQualifiedAccessExpression,
+) {
+    val dispatchReceiverClass = expression.dispatchReceiver?.resolvedType?.toRegularClassSymbol(context.session) ?: return
+    val companionClass = dispatchReceiverClass.companionObjectSymbol ?: return
+    val companionScope = companionClass.unsubstitutedScope(context)
+    val properties = companionScope.getProperties(fieldSymbol.name)
+    for (property in properties) {
+        if (property !is FirPropertySymbol) continue
+        if (property.hasBackingField) {
+            reporter.reportOn(expression.source, JAVA_FIELD_SHADOWED_BY_KOTLIN_PROPERTY, property, context)
+            break
+        }
+    }
+}

compiler/testData/codegen/box/javaFieldAndKotlinProperty/javaFieldAndCompanionProperty.kt

@@ -1,5 +1,7 @@
 // TARGET_BACKEND: JVM_IR
 // IGNORE_BACKEND_K1: JVM_IR
+// IGNORE_BACKEND_K2: JVM_IR
+// COMMENTED[LANGUAGE: +ProperFieldAccessGenerationForFieldAccessShadowedByKotlinProperty] uncomment when KT-52338 is fixed
 
 // FILE: Base.java
 public class Base {

compiler/testData/diagnostics/tests/properties/javaFieldAndKotlinProperty/javaFieldAndCompanionProperty.fir.kt

@@ -0,0 +1,29 @@
+// LANGUAGE: -ProperFieldAccessGenerationForFieldAccessShadowedByKotlinProperty
+// ISSUE: KT-52338
+
+// FILE: Base.java
+public class Base {
+    protected String TAG = "OK";
+
+    public String foo() {
+        return TAG;
+    }
+}
+
+// FILE: Sub.kt
+
+class Sub : Base() {
+    companion object {
+        val TAG = "FAIL"
+    }
+
+    fun log() = <!JAVA_FIELD_SHADOWED_BY_KOTLIN_PROPERTY!>TAG<!>
+
+    fun logReference() = this::<!JAVA_FIELD_SHADOWED_BY_KOTLIN_PROPERTY!>TAG<!>.get()
+
+    fun logAssignment(): String {
+        <!JAVA_FIELD_SHADOWED_BY_KOTLIN_PROPERTY!>TAG<!> = "12"
+        if (foo() != "12") return "Error writing: ${foo()}"
+        return "OK"
+    }
+}

compiler/testData/diagnostics/tests/properties/javaFieldAndKotlinProperty/javaFieldAndCompanionProperty.kt

@@ -0,0 +1,29 @@
+// LANGUAGE: -ProperFieldAccessGenerationForFieldAccessShadowedByKotlinProperty
+// ISSUE: KT-52338
+
+// FILE: Base.java
+public class Base {
+    protected String TAG = "OK";
+
+    public String foo() {
+        return TAG;
+    }
+}
+
+// FILE: Sub.kt
+
+class Sub : Base() {
+    companion object {
+        val TAG = "FAIL"
+    }
+
+    fun log() = TAG
+
+    fun logReference() = this::TAG.get()
+
+    fun logAssignment(): String {
+        TAG = "12"
+        if (foo() != "12") return "Error writing: ${foo()}"
+        return "OK"
+    }
+}