Preparing custom type converters (#131)

stablekernel · Jun 12, 2020 · c9903bc · c9903bc
1 parent e4ceb60
commit c9903bc
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Showing 6 changed files with 29 additions and 35 deletions.
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -1,5 +1,9 @@
 # Changelog
 
+## 2.2.0
+
+- Preparation for custom type converters.
+
 ## 2.1.1
 
 - Fix `RuneIterator.current` use, which no longer returns `null` in 2.8 SDK.

diff --git a/lib/src/query.dart b/lib/src/query.dart
@@ -209,8 +209,9 @@ class ParameterValue {
   factory ParameterValue.text(dynamic value) {
     Uint8List bytes;
     if (value != null) {
-      final converter = PostgresTextEncoder(false);
-      bytes = castBytes(utf8.encode(converter.convert(value)));
+      final converter = PostgresTextEncoder();
+      bytes = castBytes(
+          utf8.encode(converter.convert(value, escapeStrings: false)));
     }
     final length = bytes?.length ?? 0;
     return ParameterValue._(false, bytes, length);

diff --git a/lib/src/substituter.dart b/lib/src/substituter.dart
@@ -54,7 +54,7 @@ class PostgreSQLFormat {
 
   static String substitute(String fmtString, Map<String, dynamic> values,
       {SQLReplaceIdentifierFunction replace}) {
-    final converter = PostgresTextEncoder(true);
+    final converter = PostgresTextEncoder();
     values ??= <String, dynamic>{};
     replace ??= (spec, index) => converter.convert(values[spec.name]);
 

diff --git a/lib/src/text_codec.dart b/lib/src/text_codec.dart
@@ -2,45 +2,42 @@ import 'dart:convert';
 
 import 'package:postgres/postgres.dart';
 
-class PostgresTextEncoder extends Converter<dynamic, String> {
-  const PostgresTextEncoder(this._escapeStrings);
-
-  final bool _escapeStrings;
-
-  @override
-  String convert(dynamic value) {
+class PostgresTextEncoder {
+  String convert(dynamic value, {bool escapeStrings = true}) {
     if (value == null) {
       return 'null';
     }
 
     if (value is int) {
-      return encodeNumber(value);
+      return _encodeNumber(value);
     }
 
     if (value is double) {
-      return encodeDouble(value);
+      return _encodeDouble(value);
     }
 
     if (value is String) {
-      return encodeString(value, _escapeStrings);
+      return _encodeString(value, escapeStrings);
     }
 
     if (value is DateTime) {
-      return encodeDateTime(value, isDateOnly: false);
+      return _encodeDateTime(value, isDateOnly: false);
     }
 
     if (value is bool) {
-      return encodeBoolean(value);
+      return _encodeBoolean(value);
     }
 
     if (value is Map) {
-      return encodeJSON(value);
+      return _encodeJSON(value);
     }
 
+    // TODO: use custom type encoders
+
     throw PostgreSQLException("Could not infer type of value '$value'.");
   }
 
-  String encodeString(String text, bool escapeStrings) {
+  String _encodeString(String text, bool escapeStrings) {
     if (!escapeStrings) {
       return text;
     }
@@ -85,7 +82,7 @@ class PostgresTextEncoder extends Converter<dynamic, String> {
     return buf.toString();
   }
 
-  String encodeNumber(num value) {
+  String _encodeNumber(num value) {
     if (value.isNaN) {
       return "'nan'";
     }
@@ -97,7 +94,7 @@ class PostgresTextEncoder extends Converter<dynamic, String> {
     return value.toInt().toString();
   }
 
-  String encodeDouble(double value) {
+  String _encodeDouble(double value) {
     if (value.isNaN) {
       return "'nan'";
     }
@@ -109,11 +106,11 @@ class PostgresTextEncoder extends Converter<dynamic, String> {
     return value.toString();
   }
 
-  String encodeBoolean(bool value) {
+  String _encodeBoolean(bool value) {
     return value ? 'TRUE' : 'FALSE';
   }
 
-  String encodeDateTime(DateTime value, {bool isDateOnly}) {
+  String _encodeDateTime(DateTime value, {bool isDateOnly}) {
     var string = value.toIso8601String();
 
     if (isDateOnly) {
@@ -147,7 +144,7 @@ class PostgresTextEncoder extends Converter<dynamic, String> {
     return "'$string'";
   }
 
-  String encodeJSON(dynamic value) {
+  String _encodeJSON(dynamic value) {
     if (value == null) {
       return 'null';
     }

diff --git a/pubspec.yaml b/pubspec.yaml
@@ -1,6 +1,6 @@
 name: postgres
 description: PostgreSQL database driver. Supports statement reuse and binary protocol.
-version: 2.1.1
+version: 2.2.0-dev
 homepage: https://github.com/stablekernel/postgresql-dart
 
 environment:

diff --git a/test/encoding_test.dart b/test/encoding_test.dart
@@ -232,8 +232,9 @@ void main() {
   });
 
   group('Text encoders', () {
+    final encoder = PostgresTextEncoder();
+
     test('Escape strings', () {
-      final encoder = PostgresTextEncoder(true);
       //                                                       '   b   o    b   '
       expect(
           utf8.encode(encoder.convert('bob')), equals([39, 98, 111, 98, 39]));
@@ -294,9 +295,8 @@ void main() {
             DateTime(12345, DateTime.february, 3, 4, 5, 6, 0)
       };
 
-      final encoder = PostgresTextEncoder(false);
       pairs.forEach((k, v) {
-        expect(encoder.convert(v), "'$k'");
+        expect(encoder.convert(v, escapeStrings: false), "'$k'");
       });
     });
 
@@ -311,37 +311,29 @@ void main() {
         '0.0': 0.0
       };
 
-      final encoder = PostgresTextEncoder(false);
       pairs.forEach((k, v) {
-        expect(encoder.convert(v), '$k');
+        expect(encoder.convert(v, escapeStrings: false), '$k');
       });
     });
 
     test('Encode Int', () {
-      final encoder = PostgresTextEncoder(false);
-
       expect(encoder.convert(1), '1');
       expect(encoder.convert(1234324323), '1234324323');
       expect(encoder.convert(-1234324323), '-1234324323');
     });
 
     test('Encode Bool', () {
-      final encoder = PostgresTextEncoder(false);
-
       expect(encoder.convert(true), 'TRUE');
       expect(encoder.convert(false), 'FALSE');
     });
 
     test('Encode JSONB', () {
-      final encoder = PostgresTextEncoder(false);
-
       expect(encoder.convert({'a': 'b'}), '{"a":"b"}');
       expect(encoder.convert({'a': true}), '{"a":true}');
       expect(encoder.convert({'b': false}), '{"b":false}');
     });
 
     test('Attempt to infer unknown type throws exception', () {
-      final encoder = PostgresTextEncoder(false);
       try {
         encoder.convert([]);
         fail('unreachable');