Finalizing type codec API (#381)

CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
 
-## 3.4.0-dev.2
+## 3.4.0
 
 - `Connection.info` (through `ConnectionInfo` class) exposes read-only connection-level information,
   e.g. acessing access server-provided parameter status values.
@@ -12,7 +12,7 @@
   - `EncoderFn` value converter for generic Dart object -> Postgres-encoded bytes
     (for values where type is not specified).
   - `DatabaseInfo` tracks information about relations and oids (currently limited to `RelationMessage` caching).
-- **Behaviour changes**, may be breaking in some cases:
+- **Timeout-related behaviour changes**, may be breaking in some cases:
   - Preparing/executing a stamement on the main connection while in a `runTx` callback will throw an exception.
   - Setting `timeout` will try to actively cancel the current statement using a new connection.
   - `ServerException` may be transformed into `_PgQueryCancelledException` which is both `PgException` and `TimeoutException` (but no longer `ServerException`).

README.md

@@ -53,7 +53,12 @@ See the API documentation: https://pub.dev/documentation/postgres/latest/
 The library supports connection pooling (and masking the connection pool as
 regular session executor).
 
-## Additional Capabilities
+## Custom type codecs
+
+The library supports registering custom type codecs (and generic object encoders)
+through the`ConnectionSettings.typeRegistry`.
+
+## Streaming replication protocol
 
 The library supports connecting to PostgreSQL using the [Streaming Replication Protocol][].
 See [Connection][] documentation for more info.

lib/src/types.dart

@@ -405,6 +405,14 @@ abstract class Type<T extends Object> {
 
   @override
   String toString() => 'Type(oid:$oid)';
+
+  @override
+  int get hashCode => oid ?? -1;
+
+  @override
+  bool operator ==(Object other) {
+    return (other is Type) && (other.oid == oid);
+  }
 }
 
 class TypedValue<T extends Object> {

lib/src/types/type_registry.dart

@@ -237,6 +237,8 @@ final _builtInTypeNames = <String, Type>{
   '_varchar': Type.varCharArray,
 };
 
+/// Contains the static registry of type mapping from substitution names to
+/// type OIDs, their codec and the generic type encoders (for un-typed values).
 class TypeRegistry {
   final _byTypeOid = <int, Type>{};
   final _bySubstitutionName = <String, Type>{};
@@ -247,8 +249,9 @@ class TypeRegistry {
     /// Override or extend the built-in codecs using the type OID as key.
     Map<int, Codec>? codecs,
 
-    /// When encoding an untyped parameter for a query, try to use these encoders
-    /// before the built-in (generic) text encoders.
+    /// When encoding a non-typed parameter for a query, try to use these
+    /// encoders in their specified order. The encoders will be called
+    /// before the the built-in (generic) text encoders.
     Iterable<EncoderFn>? encoders,
   }) {
     _bySubstitutionName.addAll(_builtInTypeNames);

pubspec.yaml

@@ -1,6 +1,6 @@
 name: postgres
 description: PostgreSQL database driver. Supports statement reuse and binary protocol and connection pooling.
-version: 3.4.0-dev.2
+version: 3.4.0
 homepage: https://github.com/isoos/postgresql-dart
 topics:
   - sql