[FIR] Allow lateinit FirBackingField's

2021-09-08 11:47:45 +03:00
parent 871aebd423
commit 6b532ccd0d
11 changed files with 119 additions and 39 deletions
@@ -875,6 +875,9 @@ object DIAGNOSTICS_LIST : DiagnosticList("FirErrors") {
        val ACCESSOR_FOR_DELEGATED_PROPERTY by error<KtPropertyAccessor>()
        val PROPERTY_INITIALIZER_WITH_EXPLICIT_FIELD_DECLARATION by error<KtExpression>()
        val PROPERTY_FIELD_DECLARATION_MISSING_INITIALIZER by error<KtBackingField>()
+        val LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER by error<KtBackingField>(PositioningStrategy.LATEINIT_MODIFIER)
+        val LATEINIT_FIELD_IN_VAL_PROPERTY by error<KtBackingField>(PositioningStrategy.LATEINIT_MODIFIER)
+        val LATEINIT_NULLABLE_BACKING_FIELD by error<KtBackingField>(PositioningStrategy.LATEINIT_MODIFIER)
        val PROPERTY_MUST_HAVE_GETTER by error<KtProperty>()
        val PROPERTY_MUST_HAVE_SETTER by error<KtProperty>()
        val EXPLICIT_BACKING_FIELD_IN_INTERFACE by error<KtBackingField>(PositioningStrategy.FIELD_KEYWORD)
@@ -482,6 +482,9 @@ object FirErrors {
    val ACCESSOR_FOR_DELEGATED_PROPERTY by error0<KtPropertyAccessor>()
    val PROPERTY_INITIALIZER_WITH_EXPLICIT_FIELD_DECLARATION by error0<KtExpression>()
    val PROPERTY_FIELD_DECLARATION_MISSING_INITIALIZER by error0<KtBackingField>()
+    val LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER by error0<KtBackingField>(SourceElementPositioningStrategies.LATEINIT_MODIFIER)
+    val LATEINIT_FIELD_IN_VAL_PROPERTY by error0<KtBackingField>(SourceElementPositioningStrategies.LATEINIT_MODIFIER)
+    val LATEINIT_NULLABLE_BACKING_FIELD by error0<KtBackingField>(SourceElementPositioningStrategies.LATEINIT_MODIFIER)
    val PROPERTY_MUST_HAVE_GETTER by error0<KtProperty>()
    val PROPERTY_MUST_HAVE_SETTER by error0<KtProperty>()
    val EXPLICIT_BACKING_FIELD_IN_INTERFACE by error0<KtBackingField>(SourceElementPositioningStrategies.FIELD_KEYWORD)
@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.reportOn
 import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertyGetter
 import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertySetter
+import org.jetbrains.kotlin.fir.declarations.utils.hasExplicitBackingField
 import org.jetbrains.kotlin.fir.declarations.utils.isLateInit
 import org.jetbrains.kotlin.fir.types.*

@@ -44,6 +45,9 @@ object FirInapplicableLateinitChecker : FirPropertyChecker() {
                reporter.reportError(declaration.source, "is not allowed on properties of primitive types", context)
            }

+            declaration.hasExplicitBackingField ->
+                reporter.reportError(declaration.source, "must be moved to the field declaration", context)
+
            declaration.hasGetter() || declaration.hasSetter() ->
                reporter.reportError(declaration.source, "is not allowed on properties with a custom getter or setter", context)
        }
@@ -9,13 +9,17 @@ 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.FirBackingField
 import org.jetbrains.kotlin.fir.declarations.FirProperty
 import org.jetbrains.kotlin.fir.declarations.FirPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.impl.FirDefaultPropertyAccessor
 import org.jetbrains.kotlin.fir.declarations.utils.hasExplicitBackingField
+import org.jetbrains.kotlin.fir.declarations.utils.isLateInit
 import org.jetbrains.kotlin.fir.expressions.FirErrorExpression
 import org.jetbrains.kotlin.fir.typeContext
+import org.jetbrains.kotlin.fir.types.ConeTypeParameterType
 import org.jetbrains.kotlin.fir.types.coneType
+import org.jetbrains.kotlin.fir.types.isNullable
 import org.jetbrains.kotlin.fir.types.isSubtypeOf

 object FirPropertyFieldTypeChecker : FirPropertyChecker() {
@@ -35,8 +39,18 @@ object FirPropertyFieldTypeChecker : FirPropertyChecker() {
            reporter.reportOn(declaration.initializer?.source, FirErrors.PROPERTY_INITIALIZER_WITH_EXPLICIT_FIELD_DECLARATION, context)
        }

-        if (backingField.initializer == null) {
+        if (backingField.isLateInit && declaration.isVal) {
+            reporter.reportOn(backingField.source, FirErrors.LATEINIT_FIELD_IN_VAL_PROPERTY, context)
+        }
+
+        if (backingField.initializer == null && !backingField.isLateInit) {
            reporter.reportOn(backingField.source, FirErrors.PROPERTY_FIELD_DECLARATION_MISSING_INITIALIZER, context)
+        } else if (backingField.initializer != null && backingField.isLateInit) {
+            reporter.reportOn(backingField.source, FirErrors.LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER, context)
+        }
+
+        if (backingField.isLateInit && backingField.isNullable) {
+            reporter.reportOn(backingField.source, FirErrors.LATEINIT_NULLABLE_BACKING_FIELD, context)
        }

        if (backingField.returnTypeRef.coneType == declaration.returnTypeRef.coneType) {
@@ -53,6 +67,12 @@ object FirPropertyFieldTypeChecker : FirPropertyChecker() {
        }
    }

+    private val FirBackingField.isNullable
+        get() = when (val type = returnTypeRef.coneType) {
+            is ConeTypeParameterType -> type.isNullable || type.lookupTag.typeParameterSymbol.resolvedBounds.any { it.coneType.isNullable }
+            else -> type.isNullable
+        }
+
    private val FirPropertyAccessor?.isNotExplicit
        get() = this == null || this is FirDefaultPropertyAccessor

@@ -257,6 +257,9 @@ import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.INVISIBLE_REFEREN
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.IS_ENUM_ENTRY
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.ITERATOR_AMBIGUITY
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.KCLASS_WITH_NULLABLE_TYPE_PARAMETER_IN_SIGNATURE
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LATEINIT_FIELD_IN_VAL_PROPERTY
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LATEINIT_NULLABLE_BACKING_FIELD
+import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LEAKED_IN_PLACE_LAMBDA
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LOCAL_ANNOTATION_CLASS_ERROR
 import org.jetbrains.kotlin.fir.analysis.diagnostics.FirErrors.LOCAL_INTERFACE_NOT_ALLOWED
@@ -1283,6 +1286,18 @@ class FirDefaultErrorMessages {
                PROPERTY_FIELD_DECLARATION_MISSING_INITIALIZER,
                "Property backing field declaration must have an initializer"
            )
+            map.put(
+                LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER,
+                "Lateinit backing field cannot have an initializer"
+            )
+            map.put(
+                LATEINIT_FIELD_IN_VAL_PROPERTY,
+                "Only mutable properties can have a mutable backing field. Consider changing ''val'' to ''var''"
+            )
+            map.put(
+                LATEINIT_NULLABLE_BACKING_FIELD,
+                "Lateinit modifier is not allowed on backing fields of a type with nullable upper bound"
+            )
            map.put(
                PROPERTY_MUST_HAVE_GETTER,
                "This property needs a custom getter, because it's type is not a supertype of the backing field's type"
@@ -1403,6 +1403,7 @@ class DeclarationsConverter(
        return FirDeclarationStatusImpl(componentVisibility, modifiers.getModality(isClassOrObject = false)).apply {
            isInline = propertyModifiers.hasInline() || modifiers.hasInline()
            isExternal = propertyModifiers.hasExternal() || modifiers.hasExternal()
+            isLateInit = modifiers.hasLateinit()
        }
    }

@@ -463,6 +463,7 @@ open class RawFirBuilder(
                        declaration?.hasModifier(INLINE_KEYWORD) == true
                isExternal = property.hasModifier(EXTERNAL_KEYWORD) ||
                        declaration?.hasModifier(EXTERNAL_KEYWORD) == true
+                isLateInit = declaration?.hasModifier(LATEINIT_KEYWORD) == true
            }
        }

@@ -198,7 +198,12 @@ val possibleTargetMap = mapOf(
    REIFIED_KEYWORD to EnumSet.of(KotlinTarget.TYPE_PARAMETER),
    VARARG_KEYWORD to EnumSet.of(KotlinTarget.VALUE_PARAMETER, KotlinTarget.PROPERTY_PARAMETER),
    COMPANION_KEYWORD to EnumSet.of(KotlinTarget.OBJECT),
-    LATEINIT_KEYWORD to EnumSet.of(KotlinTarget.MEMBER_PROPERTY, KotlinTarget.TOP_LEVEL_PROPERTY, KotlinTarget.LOCAL_VARIABLE),
+    LATEINIT_KEYWORD to EnumSet.of(
+        KotlinTarget.MEMBER_PROPERTY,
+        KotlinTarget.TOP_LEVEL_PROPERTY,
+        KotlinTarget.LOCAL_VARIABLE,
+        KotlinTarget.BACKING_FIELD
+    ),
    DATA_KEYWORD to EnumSet.of(KotlinTarget.CLASS_ONLY, KotlinTarget.LOCAL_CLASS),
    INLINE_KEYWORD to EnumSet.of(
        KotlinTarget.FUNCTION,
@@ -2418,6 +2418,24 @@ internal val KT_DIAGNOSTIC_CONVERTER = KtDiagnosticConverterBuilder.buildConvert
            token,
        )
    }
+    add(FirErrors.LATEINIT_PROPERTY_FIELD_DECLARATION_WITH_INITIALIZER) { firDiagnostic ->
+        LateinitPropertyFieldDeclarationWithInitializerImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
+    add(FirErrors.LATEINIT_FIELD_IN_VAL_PROPERTY) { firDiagnostic ->
+        LateinitFieldInValPropertyImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
+    add(FirErrors.LATEINIT_NULLABLE_BACKING_FIELD) { firDiagnostic ->
+        LateinitNullableBackingFieldImpl(
+            firDiagnostic as FirPsiDiagnostic,
+            token,
+        )
+    }
    add(FirErrors.PROPERTY_MUST_HAVE_GETTER) { firDiagnostic ->
        PropertyMustHaveGetterImpl(
            firDiagnostic as FirPsiDiagnostic,
@@ -1711,6 +1711,18 @@ sealed class KtFirDiagnostic<PSI : PsiElement> : KtDiagnosticWithPsi<PSI> {
        override val diagnosticClass get() = PropertyFieldDeclarationMissingInitializer::class
    }

+    abstract class LateinitPropertyFieldDeclarationWithInitializer : KtFirDiagnostic<KtBackingField>() {
+        override val diagnosticClass get() = LateinitPropertyFieldDeclarationWithInitializer::class
+    }
+
+    abstract class LateinitFieldInValProperty : KtFirDiagnostic<KtBackingField>() {
+        override val diagnosticClass get() = LateinitFieldInValProperty::class
+    }
+
+    abstract class LateinitNullableBackingField : KtFirDiagnostic<KtBackingField>() {
+        override val diagnosticClass get() = LateinitNullableBackingField::class
+    }
+
    abstract class PropertyMustHaveGetter : KtFirDiagnostic<KtProperty>() {
        override val diagnosticClass get() = PropertyMustHaveGetter::class
    }
@@ -2753,6 +2753,27 @@ internal class PropertyFieldDeclarationMissingInitializerImpl(
    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }

+internal class LateinitPropertyFieldDeclarationWithInitializerImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.LateinitPropertyFieldDeclarationWithInitializer(), KtAbstractFirDiagnostic<KtBackingField> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
+internal class LateinitFieldInValPropertyImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.LateinitFieldInValProperty(), KtAbstractFirDiagnostic<KtBackingField> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
+internal class LateinitNullableBackingFieldImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.LateinitNullableBackingField(), KtAbstractFirDiagnostic<KtBackingField> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
 internal class PropertyMustHaveGetterImpl(
    firDiagnostic: FirPsiDiagnostic,
    override val token: ValidityToken,
@@ -2767,43 +2788,6 @@ internal class PropertyMustHaveSetterImpl(
    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }

-internal class AbstractPropertyInPrimaryConstructorParametersImpl(
-    firDiagnostic: FirPsiDiagnostic,
-    override val token: ValidityToken,
-) : KtFirDiagnostic.AbstractPropertyInPrimaryConstructorParameters(), KtAbstractFirDiagnostic<KtModifierListOwner> {
-    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
-}
-
-internal class LocalVariableWithTypeParametersWarningImpl(
-    firDiagnostic: FirPsiDiagnostic,
-    override val token: ValidityToken,
-) : KtFirDiagnostic.LocalVariableWithTypeParametersWarning(), KtAbstractFirDiagnostic<KtProperty> {
-    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
-}
-
-internal class LocalVariableWithTypeParametersImpl(
-    firDiagnostic: FirPsiDiagnostic,
-    override val token: ValidityToken,
-) : KtFirDiagnostic.LocalVariableWithTypeParameters(), KtAbstractFirDiagnostic<KtProperty> {
-    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
-}
-
-internal class InapplicableBackingFieldVisibilityImpl(
-    override val modifier: KtModifierKeywordToken,
-    firDiagnostic: FirPsiDiagnostic,
-    override val token: ValidityToken,
-) : KtFirDiagnostic.InapplicableBackingFieldVisibility(), KtAbstractFirDiagnostic<PsiElement> {
-    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
-}
-
-internal class InapplicableBackingFieldModifierImpl(
-    override val modifier: KtModifierKeywordToken,
-    firDiagnostic: FirPsiDiagnostic,
-    override val token: ValidityToken,
-) : KtFirDiagnostic.InapplicableBackingFieldModifier(), KtAbstractFirDiagnostic<PsiElement> {
-    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
-}
-
 internal class ExplicitBackingFieldInInterfaceImpl(
    firDiagnostic: FirPsiDiagnostic,
    override val token: ValidityToken,
@@ -2839,6 +2823,20 @@ internal class AbstractPropertyInPrimaryConstructorParametersImpl(
    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
 }

+internal class LocalVariableWithTypeParametersWarningImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.LocalVariableWithTypeParametersWarning(), KtAbstractFirDiagnostic<KtProperty> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
+internal class LocalVariableWithTypeParametersImpl(
+    firDiagnostic: FirPsiDiagnostic,
+    override val token: ValidityToken,
+) : KtFirDiagnostic.LocalVariableWithTypeParameters(), KtAbstractFirDiagnostic<KtProperty> {
+    override val firDiagnostic: FirPsiDiagnostic by weakRef(firDiagnostic)
+}
+
 internal class ExpectedDeclarationWithBodyImpl(
    firDiagnostic: FirPsiDiagnostic,
    override val token: ValidityToken,