add filters for custom objects

drift/lib/src/runtime/manager/filter.dart

@@ -1,7 +1,7 @@
 part of 'manager.dart';
 
 /// Defines a class which is used to wrap a column to only expose filter functions
-class ColumnFilters<T extends Object> {
+class ColumnFilters<T extends Object, C extends GeneratedColumn<T>> {
   /// This class is a wrapper on top of the generated column class
   ///
   /// It's used to expose filter functions for a column type
@@ -16,7 +16,7 @@ class ColumnFilters<T extends Object> {
   ColumnFilters(this.column);
 
   /// Column that this [ColumnFilters] wraps
-  GeneratedColumn<T> column;
+  C column;
 
   /// Create a filter that checks if the column is null.
   ComposableFilter isNull() => ComposableFilter.simple(column.isNull());
@@ -28,13 +28,13 @@ class ColumnFilters<T extends Object> {
   ComposableFilter equals(T value) =>
       ComposableFilter.simple(column.equals(value));
 
-  /// Create a filter that checks if the column equals a value.
+  /// Shortcut for [equals]
   ComposableFilter call(T value) =>
       ComposableFilter.simple(column.equals(value));
 }
 
 /// Built in filters for int/double columns
-extension NumFilters<T extends num> on ColumnFilters<T> {
+extension NumFilters<T extends num> on ColumnFilters<T, GeneratedColumn<T>> {
   /// Create a filter to check if the column is bigger than a value
   ComposableFilter isBiggerThan(T value) =>
       ComposableFilter.simple(column.isBiggerThanValue(value));
@@ -61,7 +61,8 @@ extension NumFilters<T extends num> on ColumnFilters<T> {
 }
 
 /// Built in filters for BigInt columns
-extension BigIntFilters<T extends BigInt> on ColumnFilters<T> {
+extension BigIntFilters<T extends BigInt>
+    on ColumnFilters<T, GeneratedColumn<T>> {
   /// Create a filter to check if the column is bigger than a value
   ComposableFilter isBiggerThan(T value) =>
       ComposableFilter.simple(column.isBiggerThanValue(value));
@@ -88,7 +89,8 @@ extension BigIntFilters<T extends BigInt> on ColumnFilters<T> {
 }
 
 /// Built in filters for String columns
-extension DateFilters<T extends DateTime> on ColumnFilters<T> {
+extension DateFilters<T extends DateTime>
+    on ColumnFilters<T, GeneratedColumn<T>> {
   /// Create a filter to check if the column is after a [DateTime]
   ComposableFilter isAfter(T value) =>
       ComposableFilter.simple(column.isBiggerThanValue(value));
@@ -115,6 +117,22 @@ extension DateFilters<T extends DateTime> on ColumnFilters<T> {
       isBetween(lower, higher)._reversed();
 }
 
+extension CustomFilters<CUSTOM, T extends Object,
+        C extends GeneratedColumnWithTypeConverter<CUSTOM, T>>
+    on ColumnFilters<T, C> {
+  /// Create a filter that checks if the column equals the columns custom type
+  ComposableFilter equals(CUSTOM value) =>
+      ComposableFilter.simple(column.equalsValue(value));
+
+  /// Create a filter that checks if the column equals the value of the columns custom type
+  ComposableFilter equalsValue(T value) =>
+      ComposableFilter.simple(column.equals(value));
+
+  /// Shortcut for [equals]
+  ComposableFilter call(CUSTOM value) =>
+      ComposableFilter.simple(column.equalsValue(value));
+}
+
 /// Defines a class that can be used to compose filters for a column
 class ComposableFilter implements HasJoinBuilders {
   @override