Don't use invalid nullable converter fields

drift/test/test_utils/test_utils.mocks.dart

@@ -64,7 +64,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: false,
         returnValueForMissingStub: false,
       ) as bool);
-
   @override
   set isInTransaction(bool? _isInTransaction) => super.noSuchMethod(
         Invocation.setter(
@@ -73,7 +72,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         ),
         returnValueForMissingStub: null,
       );
-
   @override
   _i2.DbVersionDelegate get versionDelegate => (super.noSuchMethod(
         Invocation.getter(#versionDelegate),
@@ -86,7 +84,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
           Invocation.getter(#versionDelegate),
         ),
       ) as _i2.DbVersionDelegate);
-
   @override
   _i2.TransactionDelegate get transactionDelegate => (super.noSuchMethod(
         Invocation.getter(#transactionDelegate),
@@ -99,14 +96,12 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
           Invocation.getter(#transactionDelegate),
         ),
       ) as _i2.TransactionDelegate);
-
   @override
   _i4.FutureOr<bool> get isOpen => (super.noSuchMethod(
         Invocation.getter(#isOpen),
         returnValue: _i4.Future<bool>.value(false),
         returnValueForMissingStub: _i4.Future<bool>.value(false),
       ) as _i4.FutureOr<bool>);
-
   @override
   _i4.Future<void> open(_i5.QueryExecutorUser? db) => (super.noSuchMethod(
         Invocation.method(
@@ -116,7 +111,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: _i4.Future<void>.value(),
         returnValueForMissingStub: _i4.Future<void>.value(),
       ) as _i4.Future<void>);
-
   @override
   _i4.Future<void> close() => (super.noSuchMethod(
         Invocation.method(
@@ -126,7 +120,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: _i4.Future<void>.value(),
         returnValueForMissingStub: _i4.Future<void>.value(),
       ) as _i4.Future<void>);
-
   @override
   void notifyDatabaseOpened(_i5.OpeningDetails? details) => super.noSuchMethod(
         Invocation.method(
@@ -135,7 +128,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         ),
         returnValueForMissingStub: null,
       );
-
   @override
   _i4.Future<_i3.QueryResult> runSelect(
     String? statement,
@@ -171,7 +163,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
           ),
         )),
       ) as _i4.Future<_i3.QueryResult>);
-
   @override
   _i4.Future<int> runUpdate(
     String? statement,
@@ -188,7 +179,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: _i4.Future<int>.value(0),
         returnValueForMissingStub: _i4.Future<int>.value(0),
       ) as _i4.Future<int>);
-
   @override
   _i4.Future<int> runInsert(
     String? statement,
@@ -205,7 +195,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: _i4.Future<int>.value(0),
         returnValueForMissingStub: _i4.Future<int>.value(0),
       ) as _i4.Future<int>);
-
   @override
   _i4.Future<void> runCustom(
     String? statement,
@@ -222,7 +211,6 @@ class MockDatabaseDelegate extends _i1.Mock implements _i2.DatabaseDelegate {
         returnValue: _i4.Future<void>.value(),
         returnValueForMissingStub: _i4.Future<void>.value(),
       ) as _i4.Future<void>);
-
   @override
   _i4.Future<void> runBatched(_i5.BatchedStatements? statements) =>
       (super.noSuchMethod(
@@ -246,7 +234,6 @@ class MockDynamicVersionDelegate extends _i1.Mock
         returnValue: _i4.Future<int>.value(0),
         returnValueForMissingStub: _i4.Future<int>.value(0),
       ) as _i4.Future<int>);
-
   @override
   _i4.Future<void> setSchemaVersion(int? version) => (super.noSuchMethod(
         Invocation.method(
@@ -269,7 +256,6 @@ class MockSupportedTransactionDelegate extends _i1.Mock
         returnValue: false,
         returnValueForMissingStub: false,
       ) as bool);
-
   @override
   _i4.FutureOr<void> startTransaction(
           _i4.Future<dynamic> Function(_i2.QueryDelegate)? run) =>
@@ -298,7 +284,6 @@ class MockStreamQueries extends _i1.Mock implements _i6.StreamQueryStore {
         returnValueForMissingStub:
             _i4.Stream<List<Map<String, Object?>>>.empty(),
       ) as _i4.Stream<List<Map<String, Object?>>>);
-
   @override
   _i4.Stream<Set<_i5.TableUpdate>> updatesForSync(
           _i5.TableUpdateQuery? query) =>
@@ -310,7 +295,6 @@ class MockStreamQueries extends _i1.Mock implements _i6.StreamQueryStore {
         returnValue: _i4.Stream<Set<_i5.TableUpdate>>.empty(),
         returnValueForMissingStub: _i4.Stream<Set<_i5.TableUpdate>>.empty(),
       ) as _i4.Stream<Set<_i5.TableUpdate>>);
-
   @override
   void handleTableUpdates(Set<_i5.TableUpdate>? updates) => super.noSuchMethod(
         Invocation.method(
@@ -319,7 +303,6 @@ class MockStreamQueries extends _i1.Mock implements _i6.StreamQueryStore {
         ),
         returnValueForMissingStub: null,
       );
-
   @override
   void markAsClosed(
     _i6.QueryStream? stream,
@@ -335,7 +318,6 @@ class MockStreamQueries extends _i1.Mock implements _i6.StreamQueryStore {
         ),
         returnValueForMissingStub: null,
       );
-
   @override
   void markAsOpened(_i6.QueryStream? stream) => super.noSuchMethod(
         Invocation.method(
@@ -344,7 +326,6 @@ class MockStreamQueries extends _i1.Mock implements _i6.StreamQueryStore {
         ),
         returnValueForMissingStub: null,
       );
-
   @override
   _i4.Future<void> close() => (super.noSuchMethod(
         Invocation.method(

drift_dev/CHANGELOG.md

@@ -1,6 +1,8 @@
 ## 2.13.1-dev
 
 - Add `has_separate_analyzer` option to optimize builds using the `not_shared` builder.
+- Avoid illegal references to implicitly nullable variant of type converter when no such
+  field exists.
 
 ## 2.13.0
 

drift_dev/lib/src/analysis/results/column.dart

@@ -192,7 +192,11 @@ class AppliedTypeConverter {
   /// column, drift generates a new wrapped type converter which will deal with
   /// `null` values.
   /// That converter is stored in this field.
-  String get nullableFieldName => '${fieldName}n';
+  String get nullableFieldName {
+    assert(canBeSkippedForNulls && owningColumn?.nullable == true);
+
+    return '${fieldName}n';
+  }
 
   AppliedTypeConverter({
     required this.expression,

drift_dev/lib/src/writer/tables/table_writer.dart

@@ -49,7 +49,7 @@ abstract class TableOrViewWriter {
       buffer.write('static $typeName ${converter.fieldName} = $code;');
 
       // Generate wrappers for non-nullable type converters that are applied to
-      // nullable converters.
+      // nullable columns.
       final column = converter.owningColumn!;
       if (converter.canBeSkippedForNulls && column.nullable) {
         final nullableTypeName = emitter.dartCode(

drift_dev/lib/src/writer/writer.dart

@@ -99,34 +99,39 @@ abstract class _NodeOrWriter {
   /// Returns a Dart expression evaluating to the [converter].
   AnnotatedDartCode readConverter(AppliedTypeConverter converter,
       {bool forNullable = false}) {
-    if (converter.owningColumn == null) {
-      // Type converters applied to individual columns in the result set of a
-      // `SELECT` query don't have an owning table. We instead write the
-      // expression here.
-      return AnnotatedDartCode.build((b) {
-        final implicitlyNullable =
-            converter.canBeSkippedForNulls && forNullable;
-
-        if (implicitlyNullable) {
-          b.addSymbol('NullAwareTypeConverter.wrap(', AnnotatedDartCode.drift);
+    return AnnotatedDartCode.build((b) {
+      final owningColumn = converter.owningColumn;
+      final needsImplicitNullableVersion =
+          forNullable && converter.canBeSkippedForNulls;
+      final hasNullableVariantInField = owningColumn != null &&
+          converter.canBeSkippedForNulls &&
+          owningColumn.nullable;
+
+      void addRegularConverter() {
+        if (owningColumn != null) {
+          b
+            ..addCode(entityInfoType(owningColumn.owner))
+            ..addText('.${converter.fieldName}');
+        } else {
+          // There's no field storing this converter, so evaluate it every time
+          // it is used.
+          b.addCode(converter.expression);
         }
+      }
 
-        b.addCode(converter.expression);
-
-        if (implicitlyNullable) {
+      switch ((needsImplicitNullableVersion, hasNullableVariantInField)) {
+        case (false, _):
+          addRegularConverter();
+        case (true, false):
+          b.addSymbol('NullAwareTypeConverter.wrap(', AnnotatedDartCode.drift);
+          b.addCode(converter.expression);
           b.addText(')');
-        }
-      });
-    } else {
-      final fieldName = forNullable && converter.canBeSkippedForNulls
-          ? converter.nullableFieldName
-          : converter.fieldName;
-
-      return AnnotatedDartCode([
-        ...entityInfoType(converter.owningColumn!.owner).elements,
-        '.$fieldName',
-      ]);
-    }
+        case (true, true):
+          b
+            ..addCode(entityInfoType(converter.owningColumn!.owner))
+            ..addText('.${converter.nullableFieldName}');
+      }
+    });
   }
 
   /// A suitable typename to store an instance of the type converter used here.

drift_dev/test/writer/writer_test.dart

@@ -88,4 +88,36 @@ class Database {}
       ))
     }, result.dartOutputs, result.writer);
   }, skip: requireDart('3.0.0-dev'));
+
+  test(
+    'references nullable variant of converter on non-nullable column',
+    () async {
+      final result = await emulateDriftBuild(
+        inputs: {
+          'a|lib/converter.dart': '''
+import 'package:drift/drift.dart';
+
+TypeConverter<int, String> get testConverter => throw '';
+''',
+          'a|lib/a.drift': '''
+import 'converter.dart';
+
+CREATE TABLE foo (
+  bar TEXT MAPPED BY `testConverter` NOT NULL
+);
+
+CREATE VIEW a AS SELECT nullif(bar, '') FROM foo;
+''',
+        },
+        modularBuild: true,
+        logger: loggerThat(neverEmits(anything)),
+      );
+
+      checkOutputs({
+        'a|lib/a.drift.dart': decodedMatches(
+          allOf(isNot(contains('converterbarn'))),
+        ),
+      }, result.dartOutputs, result.writer);
+    },
+  );
 }