reduce the use of trailing commas; add blank lines between groups of fields

CHANGELOG.md

@@ -1,3 +1,9 @@
+## 4.4.1-dev
+
+* Only use trailing commas if a collection (parameter list, ...) has many
+  elements.
+* Don't use trailing commas for parameters lists without optional arguments.
+
 ## 4.4.0
 
 * Mention how the `allocator` argument relates to imports in the `DartEmitter`

lib/src/emitter.dart

@@ -141,16 +141,22 @@ class DartEmitter extends Object
       visitConstructor(c, spec.name, out);
       out.writeln();
     }
-    for (var f in spec.fields) {
-      visitField(f, out);
+    if (spec.fields.isNotEmpty) {
       out.writeln();
-    }
-    for (var m in spec.methods) {
-      visitMethod(m, out);
-      if (_isLambdaMethod(m)) {
-        out.write(';');
+      for (var f in spec.fields) {
+        visitField(f, out);
+        out.writeln();
       }
+    }
+    if (spec.methods.isNotEmpty) {
       out.writeln();
+      for (var m in spec.methods) {
+        visitMethod(m, out);
+        if (_isLambdaMethod(m)) {
+          out.write(';');
+        }
+        out.writeln();
+      }
     }
     out.writeln(' }');
     return out;
@@ -223,8 +229,7 @@ class DartEmitter extends Object
       for (final p in spec.requiredParameters) {
         count++;
         _visitParameter(p, output);
-        if (hasMultipleParameters ||
-            spec.requiredParameters.length != count ||
+        if (spec.requiredParameters.length != count ||
             spec.optionalParameters.isNotEmpty) {
           output.write(', ');
         }
@@ -391,7 +396,7 @@ class DartEmitter extends Object
         spec.assignment!.accept(this, output);
       });
     }
-    output.writeln(';');
+    output.write(';');
     return output;
   }
 
@@ -585,8 +590,7 @@ class DartEmitter extends Object
         for (final p in spec.requiredParameters) {
           count++;
           _visitParameter(p, output);
-          if (hasMultipleParameters ||
-              spec.requiredParameters.length != count ||
+          if (spec.requiredParameters.length != count ||
               spec.optionalParameters.isNotEmpty) {
             output.write(', ');
           }

lib/src/specs/expression.dart

@@ -499,7 +499,7 @@ abstract class ExpressionEmitter implements ExpressionVisitor<StringSink> {
       });
       final argumentCount = expression.positionalArguments.length +
           expression.namedArguments.length;
-      if (argumentCount > 1) {
+      if (argumentCount > 3) {
         out.write(', ');
       }
       return out..write(')');
@@ -540,7 +540,7 @@ abstract class ExpressionEmitter implements ExpressionVisitor<StringSink> {
       visitAll<Object?>(expression.values, out, (value) {
         _acceptLiteral(value, out);
       });
-      if (expression.values.length > 1) {
+      if (expression.values.length > 3) {
         out.write(', ');
       }
       return out..write(']');

pubspec.yaml

@@ -1,5 +1,5 @@
 name: code_builder
-version: 4.4.0
+version: 4.4.1-dev
 description: >-
   A fluent, builder-based library for generating valid Dart code
 repository: https://github.com/dart-lang/code_builder

test/e2e/injection_test.dart

@@ -45,7 +45,7 @@ void main() {
           final Module _module;
 
           @override
-          Thing getThing() => Thing(_module.get1(), _module.get2(), );
+          Thing getThing() => Thing(_module.get1(), _module.get2());
         }
       '''),
     );
@@ -59,7 +59,7 @@ void main() {
           final _i2.Module _module;
 
           @override
-          _i3.Thing getThing() => _i3.Thing(_module.get1(), _module.get2(), );
+          _i3.Thing getThing() => _i3.Thing(_module.get1(), _module.get2());
         }
       ''', DartEmitter(allocator: Allocator.simplePrefixing())),
     );

test/specs/code/expression_test.dart

@@ -190,7 +190,7 @@ void main() {
         literal(2),
         literal(3),
       ]),
-      equalsDart('foo(1, 2, 3, )'),
+      equalsDart('foo(1, 2, 3)'),
     );
   });
 
@@ -209,7 +209,7 @@ void main() {
         'bar': literal(1),
         'baz': literal(2),
       }),
-      equalsDart('foo(bar: 1, baz: 2, )'),
+      equalsDart('foo(bar: 1, baz: 2)'),
     );
   });
 
@@ -221,7 +221,7 @@ void main() {
         'bar': literal(2),
         'baz': literal(3),
       }),
-      equalsDart('foo(1, bar: 2, baz: 3, )'),
+      equalsDart('foo(1, bar: 2, baz: 3)'),
     );
   });
 
@@ -373,7 +373,7 @@ void main() {
         literalString('foo'),
         Method((b) => b..body = literalTrue.code).closure,
       ]),
-      equalsDart("map.putIfAbsent('foo', () => true, )"),
+      equalsDart("map.putIfAbsent('foo', () => true)"),
     );
   });
 
@@ -385,7 +385,7 @@ void main() {
           ..types.add(refer('T'))
           ..body = literalTrue.code).genericClosure,
       ]),
-      equalsDart("map.putIfAbsent('foo', <T>() => true, )"),
+      equalsDart("map.putIfAbsent('foo', <T>() => true)"),
     );
   });
 

test/specs/enum_test.dart

@@ -254,7 +254,6 @@ void main() {
       ]);
 
       final int? myInt;
-
       final String? myString;
     }
     '''));
@@ -336,7 +335,6 @@ void main() {
       const MyEnum([this.myInt]);
 
       final int? myInt;
-
       static const String myString = 'abc';
     }
     '''));

test/specs/method_test.dart

@@ -464,7 +464,7 @@ void main() {
           ]),
       ),
       equalsDart(r'''
-        foo<T extends Iterable>(T t, X<T> x, );
+        foo<T extends Iterable>(T t, X<T> x);
       '''),
     );
   });