FIR: introduce three diagnostics for const val

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

@@ -1430,6 +1430,25 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
             token,
         )
     }
+    add(FirErrors.TYPE_CANT_BE_USED_FOR_CONST_VAL) { firDiagnostic ->
+        TypeCantBeUsedForConstValImpl(
+            firSymbolBuilder.typeBuilder.buildKtType(firDiagnostic.a),
+            firDiagnostic as FirPsiDiagnostic<*>,
+            token,
+        )
+    }
+    add(FirErrors.CONST_VAL_WITHOUT_INITIALIZER) { firDiagnostic ->
+        ConstValWithoutInitializerImpl(
+            firDiagnostic as FirPsiDiagnostic<*>,
+            token,
+        )
+    }
+    add(FirErrors.CONST_VAL_WITH_NON_CONST_INITIALIZER) { firDiagnostic ->
+        ConstValWithNonConstInitializerImpl(
+            firDiagnostic as FirPsiDiagnostic<*>,
+            token,
+        )
+    }
     add(FirErrors.WRONG_SETTER_PARAMETER_TYPE) { firDiagnostic ->
         WrongSetterParameterTypeImpl(
             firSymbolBuilder.typeBuilder.buildKtType(firDiagnostic.a),

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

@@ -1011,6 +1011,19 @@ sealed class KtFirDiagnostic<PSI: PsiElement> : KtDiagnosticWithPsi<PSI> {
         override val diagnosticClass get() = ConstValWithDelegate::class
     }
 
+    abstract class TypeCantBeUsedForConstVal : KtFirDiagnostic<KtProperty>() {
+        override val diagnosticClass get() = TypeCantBeUsedForConstVal::class
+        abstract val constValType: KtType
+    }
+
+    abstract class ConstValWithoutInitializer : KtFirDiagnostic<KtProperty>() {
+        override val diagnosticClass get() = ConstValWithoutInitializer::class
+    }
+
+    abstract class ConstValWithNonConstInitializer : KtFirDiagnostic<KtExpression>() {
+        override val diagnosticClass get() = ConstValWithNonConstInitializer::class
+    }
+
     abstract class WrongSetterParameterType : KtFirDiagnostic<KtTypeReference>() {
         override val diagnosticClass get() = WrongSetterParameterType::class
         abstract val expectedType: KtType

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

@@ -1636,6 +1636,28 @@ internal class ConstValWithDelegateImpl(
     override val firDiagnostic: FirPsiDiagnostic<*> by weakRef(firDiagnostic)
 }
 
+internal class TypeCantBeUsedForConstValImpl(
+    override val constValType: KtType,
+    firDiagnostic: FirPsiDiagnostic<*>,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.TypeCantBeUsedForConstVal(), KtAbstractFirDiagnostic<KtProperty> {
+    override val firDiagnostic: FirPsiDiagnostic<*> by weakRef(firDiagnostic)
+}
+
+internal class ConstValWithoutInitializerImpl(
+    firDiagnostic: FirPsiDiagnostic<*>,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.ConstValWithoutInitializer(), KtAbstractFirDiagnostic<KtProperty> {
+    override val firDiagnostic: FirPsiDiagnostic<*> by weakRef(firDiagnostic)
+}
+
+internal class ConstValWithNonConstInitializerImpl(
+    firDiagnostic: FirPsiDiagnostic<*>,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.ConstValWithNonConstInitializer(), KtAbstractFirDiagnostic<KtExpression> {
+    override val firDiagnostic: FirPsiDiagnostic<*> by weakRef(firDiagnostic)
+}
+
 internal class WrongSetterParameterTypeImpl(
     override val expectedType: KtType,
     override val actualType: KtType,