FIR: Add FirVisibilityQualifierChecker

compiler/fir/checkers/src/org/jetbrains/kotlin/fir/analysis/checkers/CommonExpressionCheckers.kt

@@ -135,6 +135,7 @@ object CommonExpressionCheckers : ExpressionCheckers() {
             FirStandaloneQualifierChecker,
             FirOptInUsageQualifierChecker,
             FirDeprecatedQualifierChecker,
+            FirVisibilityQualifierChecker,
         )
 
     override val equalityOperatorCallCheckers: Set<FirEqualityOperatorCallChecker>

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

@@ -0,0 +1,58 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.analysis.checkers.expression
+
+import org.jetbrains.kotlin.fir.analysis.checkers.context.CheckerContext
+import org.jetbrains.kotlin.fir.analysis.diagnostics.DiagnosticReporter
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors
+import org.jetbrains.kotlin.fir.analysis.diagnostics.reportOn
+import org.jetbrains.kotlin.fir.declarations.FirFile
+import org.jetbrains.kotlin.fir.declarations.FirMemberDeclaration
+import org.jetbrains.kotlin.fir.declarations.FirTypeAlias
+import org.jetbrains.kotlin.fir.declarations.utils.expandedConeType
+import org.jetbrains.kotlin.fir.expressions.FirResolvedQualifier
+import org.jetbrains.kotlin.fir.getOwnerLookupTag
+import org.jetbrains.kotlin.fir.resolve.toSymbol
+import org.jetbrains.kotlin.fir.symbols.SymbolInternals
+import org.jetbrains.kotlin.fir.symbols.impl.FirClassLikeSymbol
+import org.jetbrains.kotlin.fir.types.toSymbol
+import org.jetbrains.kotlin.fir.visibilityChecker
+
+object FirVisibilityQualifierChecker : FirResolvedQualifierChecker() {
+    override fun check(expression: FirResolvedQualifier, context: CheckerContext, reporter: DiagnosticReporter) {
+        checkClassLikeSymbol(expression.symbol ?: return, expression, context, reporter)
+    }
+
+    @OptIn(SymbolInternals::class)
+    private fun checkClassLikeSymbol(
+        symbol: FirClassLikeSymbol<*>,
+        expression: FirResolvedQualifier,
+        context: CheckerContext,
+        reporter: DiagnosticReporter
+    ) {
+        val firFile = context.containingDeclarations.firstOrNull() as? FirFile ?: return
+        val firClassLikeDeclaration = symbol.fir
+        if (firClassLikeDeclaration !is FirMemberDeclaration) return
+
+        if (!context.session.visibilityChecker.isVisible(
+                firClassLikeDeclaration, context.session, firFile, context.containingDeclarations,
+                dispatchReceiver = null,
+            )) {
+            reporter.reportOn(expression.source, FirErrors.INVISIBLE_REFERENCE, symbol, context)
+            return
+        }
+
+        if (firClassLikeDeclaration is FirTypeAlias) {
+            (firClassLikeDeclaration.expandedConeType?.toSymbol(context.session) as? FirClassLikeSymbol)?.let {
+                checkClassLikeSymbol(it, expression, context, reporter)
+            }
+        }
+
+        symbol.getOwnerLookupTag()?.toSymbol(context.session)?.let {
+            checkClassLikeSymbol(it, expression, context, reporter)
+        }
+    }
+}

compiler/testData/diagnostics/tests/classObjects/nestedClassInPrivateClassObject.fir.kt

@@ -10,6 +10,6 @@ class A {
     }
 }
 
-fun <!EXPOSED_FUNCTION_RETURN_TYPE!>f1<!>() = A.Companion.B.C
+fun <!EXPOSED_FUNCTION_RETURN_TYPE!>f1<!>() = A.Companion.B.<!INVISIBLE_REFERENCE!>C<!>
 
-fun f2() = A.Companion.B.C.foo()
+fun f2() = A.Companion.B.<!INVISIBLE_REFERENCE!>C<!>.foo()

compiler/testData/diagnostics/tests/imports/ImportPrivateMemberFromOtherFile.fir.kt

@@ -21,6 +21,6 @@ import A.Nested.*
 import B.JC.JC1
 
 fun test() {
-    O1
+    <!INVISIBLE_REFERENCE!>O1<!>
     JC1()
-}
+}

compiler/testData/diagnostics/tests/imports/ImportPrivateMembersWithStar.fir.kt

@@ -28,5 +28,5 @@ fun testAccess() {
     E1
     NestedEntry
     A1()
-    A2
-}
+    <!INVISIBLE_REFERENCE!>A2<!>
+}

compiler/testData/diagnostics/tests/j+k/privateNestedClassStaticMember.fir.kt

@@ -14,5 +14,5 @@ public class Foo {
 // FILE: 1.kt
 
 fun main() {
-    javaPackage.Foo.Bar.doSmth()
-}
+    javaPackage.Foo.<!INVISIBLE_REFERENCE!>Bar<!>.doSmth()
+}

compiler/testData/diagnostics/tests/typealias/privateInFile.fir.kt

@@ -7,10 +7,10 @@ private class C {
 private typealias TA = C
 
 private val test1: C = <!INVISIBLE_REFERENCE!>C<!>()
-private val test1co: C.Companion = <!INITIALIZER_TYPE_MISMATCH, NO_COMPANION_OBJECT!>C<!>
+private val test1co: C.Companion = <!INITIALIZER_TYPE_MISMATCH, INVISIBLE_REFERENCE, NO_COMPANION_OBJECT!>C<!>
 
 private val test2: TA = <!INITIALIZER_TYPE_MISMATCH!>TA(<!NO_VALUE_FOR_PARAMETER!>)<!><!>
-private val test2co = TA
+private val test2co = <!INVISIBLE_REFERENCE!>TA<!>
 
 // FILE: file2.kt
 private val test1: C = C()