[FIR] Prohibit class literals with empty left-hand side

^KT-59165 Fixed

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDataClassConverters.kt

@@ -2440,6 +2440,12 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
+    add(FirErrors.UNSUPPORTED_CLASS_LITERALS_WITH_EMPTY_LHS) { firDiagnostic ->
+        UnsupportedClassLiteralsWithEmptyLhsImpl(
+            firDiagnostic as KtPsiDiagnostic,
+            token,
+        )
+    }
     add(FirErrors.NOTHING_TO_OVERRIDE) { firDiagnostic ->
         NothingToOverrideImpl(
             firSymbolBuilder.callableBuilder.buildCallableSymbol(firDiagnostic.a),

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnostics.kt

@@ -1730,6 +1730,10 @@ sealed interface KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
         val lhsType: KtType
     }
 
+    interface UnsupportedClassLiteralsWithEmptyLhs : KtFirDiagnostic<KtElement> {
+        override val diagnosticClass get() = UnsupportedClassLiteralsWithEmptyLhs::class
+    }
+
     interface NothingToOverride : KtFirDiagnostic<KtModifierListOwner> {
         override val diagnosticClass get() = NothingToOverride::class
         val declaration: KtCallableSymbol

analysis/analysis-api-fir/src/org/jetbrains/kotlin/analysis/api/fir/diagnostics/KtFirDiagnosticsImpl.kt

@@ -2080,6 +2080,11 @@ internal class ExpressionOfNullableTypeInClassLiteralLhsImpl(
     token: KtLifetimeToken,
 ) : KtAbstractFirDiagnostic<PsiElement>(firDiagnostic, token), KtFirDiagnostic.ExpressionOfNullableTypeInClassLiteralLhs
 
+internal class UnsupportedClassLiteralsWithEmptyLhsImpl(
+    firDiagnostic: KtPsiDiagnostic,
+    token: KtLifetimeToken,
+) : KtAbstractFirDiagnostic<KtElement>(firDiagnostic, token), KtFirDiagnostic.UnsupportedClassLiteralsWithEmptyLhs
+
 internal class NothingToOverrideImpl(
     override val declaration: KtCallableSymbol,
     firDiagnostic: KtPsiDiagnostic,

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java

@@ -297,6 +297,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("emptyLhsClassLiterals.kt")
+        public void testEmptyLhsClassLiterals() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/emptyLhsClassLiterals.kt");
+        }
+
         @Test
         @TestMetadata("EnumEntryAsType.kt")
         public void testEnumEntryAsType() throws Exception {

analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java

@@ -297,6 +297,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
             runTest("compiler/testData/diagnostics/tests/Dollar.kt");
         }
 
+        @Test
+        @TestMetadata("emptyLhsClassLiterals.kt")
+        public void testEmptyLhsClassLiterals() throws Exception {
+            runTest("compiler/testData/diagnostics/tests/emptyLhsClassLiterals.kt");
+        }
+
         @Test
         @TestMetadata("EnumEntryAsType.kt")
         public void testEnumEntryAsType() throws Exception {