refactor: migrate member_ordering rule

[solid-illiaaihistov]

Closes #252

[solid-illiaaihistov]

/gemini review

[gemini-code-assist]

Code Review

This pull request refactors the member_ordering lint rule to extend SolidMultiLintRule (a new base class for rules with multiple diagnostic codes), splits several model classes into separate files, and replaces the old test file with a comprehensive unit test suite. The review feedback correctly identifies two critical compilation errors in MemberOrderingVisitor: first, the use of the non-existent BlockClassBody class, and second, attempting to access a .name property on ConstructorDeclaration.typeName (which is a Token and should use .lexeme instead).

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[solid-danylosafonov]

I think some of the blocks in this method should be extracted:

void _visitClassDeclaration(ClassDeclaration node) {
    final type = node.extendsClause?.superclass.type;
    final isFlutterWidget =
        isWidgetOrSubclass(type) || isWidgetStateOrSubclass(type);

    final body = node.body;
    if (body is BlockClassBody) {
      for (final member in body.members) {
        if (member is FieldDeclaration) {
          _visitFieldDeclaration(member, isFlutterWidget);
        } else if (member is ConstructorDeclaration) {
          _visitConstructorDeclaration(member, isFlutterWidget);
        } else if (member is MethodDeclaration) {
          _visitMethodDeclaration(member, isFlutterWidget);
        }
      }
    }
}

void _reportWrongOrder() {
    final wrongOrderMembers = _membersInfo.where(
      (info) => info.memberOrder.isWrong,
    );

    for (final memberInfo in wrongOrderMembers) {
      final memberGroup = memberInfo.memberOrder.memberGroup;
      final previousMemberGroup = memberInfo.memberOrder.previousMemberGroup;

      _rule.reportAtNode(
        memberInfo.classMember,
        diagnosticCode: MemberOrderingRule.wrongOrderCode,
        arguments: [
          memberGroup.toString(),
          previousMemberGroup?.toString() ?? '',
        ],
      );
    }
}

void _reportAlphabeticalOrder() {
      final alphabeticallyWrongOrderMembers = _membersInfo.where(
        (info) => info.memberOrder.isAlphabeticallyWrong,
      );

      for (final memberInfo in alphabeticallyWrongOrderMembers) {
        final names = memberInfo.memberOrder.memberNames;
        _rule.reportAtNode(
          memberInfo.classMember,
          diagnosticCode: MemberOrderingRule.alphabeticalOrderCode,
          arguments: [
            names.currentName,
            names.previousName ?? '',
          ],
        );
      }
}

void _reportAlphabeticalTypeOrder() {
final alphabeticallyByTypeWrongOrderMembers = _membersInfo.where(
        (info) => info.memberOrder.isByTypeWrong,
      );

      for (final memberInfo in alphabeticallyByTypeWrongOrderMembers) {
        final names = memberInfo.memberOrder.memberNames;
        _rule.reportAtNode(
          memberInfo.classMember,
          diagnosticCode: MemberOrderingRule.alphabeticalByTypeOrderCode,
          arguments: [
            names.currentName,
            names.previousName ?? '',
          ],
        );
      }
}

  void _reportMembers(bool Function(MemberInfo) filter, DiagnosticCode code) {
    final filtered = _membersInfo.where(filter);

    for (final memberInfo in filtered) {
      final names = memberInfo.memberOrder.memberNames;
      _rule.reportAtNode(
        memberInfo.classMember,
        diagnosticCode: code,
        arguments: [
          names.currentName,
          names.previousName ?? '',
        ],
      );
    }
  }

// Similar repetition in _visitX

I feel like we should also extract the bool _isXGroup methods into an extension on MemberGroup and move it to a separate file

[solid-illiaaihistov]

Implemented the refactoring!

[solid-danylosafonov]

Looks like all the callers only use .memberOrder anyway

Suggested change

	arguments: getArguments(memberInfo),
	arguments: getArguments(memberInfo.memberOrder),

[solid-illiaaihistov]

Done!

[solid-danylosafonov]

Suggested change

	required String name,
	required Token? token,

and then do token?.name.lexeme ?? '' inside to make the calls shorter

[solid-illiaaihistov]

Done!

[solid-danylosafonov]

I played around refactoring it and I was able to get rid of this file completely:

lib/src/utils/implies.dart:

/// Logical implication operation.
extension BoolImplies on bool {
  /// Logical implication operation.
  ///
  /// True implies that [other] is also true.
  // ignore: avoid_positional_boolean_parameters
  bool implies(bool other) => objectImplies(this, other, false);
}

/// Sugar syntax helper to write extensions analogus to bool implies.
///
/// A truthy (!= [falsy]) value of [a] implies an equal value of [b].
bool objectImplies<T>(T a, T b, T falsy) => a == falsy || a == b;

/// A class that supports logical implication of it's objects.
abstract class Implicable {
  /// Logical implication operation.
  ///
  /// A truthy value of this object implies an equal value of [other].
  bool implies(Implicable other);
}

Add a new method to abstract class MemberGroup:

  abstract class MemberGroup implements Implicable {

...

  @override
  bool implies(covariant MemberGroup other) =>
      modifier.implies(other.modifier) && annotation.implies(other.annotation);
}

and same for subclasses and relevant enums:

  @override
  bool implies(covariant ConstructorMemberGroup other) =>
      isFactory.implies(other.isFactory) && isNamed.implies(other.isNamed);

  @override
  bool implies(covariant FieldMemberGroup other) =>
      isLate.implies(other.isLate) &&
      isStatic.implies(other.isStatic) &&
      isNullable.implies(other.isNullable) &&
      keyword.implies(other.keyword);

  @override
  bool implies(covariant Modifier other) =>
      objectImplies(this, other, Modifier.unset);

  @override
  bool implies(covariant Annotation other) =>
      objectImplies(this, other, Annotation.unset);

  @override
  bool implies(covariant FieldKeyword other) =>
      objectImplies(this, other, FieldKeyword.unset);

  @override
  bool implies(MemberGroup other) =>
      super.implies(other) &&
      other is MethodMemberGroup &&
      isStatic.implies(other.isStatic) &&
      isNullable.implies(other.isNullable) &&
      name.implies(other.name);
}

extension on String? {
  bool implies(String? other) => objectImplies(this, other, null);
}

  @override
  bool implies(covariant FieldMemberGroup other) =>
      isLate.implies(other.isLate) &&
      isStatic.implies(other.isStatic) &&
      isNullable.implies(other.isNullable) &&
      keyword.implies(other.keyword);

One thing I'm not entirely sure about is covariant - maybe we should just check is in the method instead.

WDYT?

[solid-illiaaihistov]

I implemented the implies pattern, but dropped covariant to maintain compile-time type safety.

I also decided to drop the Implicable interface entirely. Since we cannot implement interfaces for primitive types like bool and String?, dropping it allowed me to keep a uniform, consistent approach across the codebase using just extensions and method overrides.

In case you still want to add the Implicable class, we can use a generic Implicable<T> to get rid of covariant.

[solid-danylosafonov]

nvm I think that won't work because for simple case we need more then just ==unset

[solid-illiaaihistov]

I think that's a great idea!

[solid-danylosafonov]

Let's leave that part as-is

[solid-danylosafonov]

We can split it into 3 classes

// MIT License
//
// Copyright (c) 2020-2021 Dart Code Checker team
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import 'package:analyzer/dart/ast/ast.dart' hide Annotation;
import 'package:analyzer/dart/ast/visitor.dart';
import 'package:solid_lints/src/lints/member_ordering/member_ordering_rule.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_ordering_parameters.dart';
import 'package:solid_lints/src/lints/member_ordering/visitors/declaration_ordering_visitor.dart';
import 'package:solid_lints/src/lints/member_ordering/visitors/member_ordering_reporter.dart';
import 'package:solid_lints/src/utils/types_utils.dart';

/// AST Visitor which finds all class members and checks if they are
/// in order provided from rule config or default config
class MemberOrderingVisitor extends SimpleAstVisitor<void> {
  final MemberOrderingRule _rule;
  final MemberOrderingParameters _parameters;

  /// Creates instance of [MemberOrderingVisitor]
  MemberOrderingVisitor(this._rule, this._parameters);

  @override
  void visitClassDeclaration(ClassDeclaration node) {
    super.visitClassDeclaration(node);

    final body = node.body;
    if (body is! BlockClassBody) return;

    final type = node.extendsClause?.superclass.type;
    final declarationVisitor = DeclarationOrderingVisitor(
      parameters: _parameters,
      isFlutterWidget:
          isWidgetOrSubclass(type) || isWidgetStateOrSubclass(type),
    );

    body.members.forEach(declarationVisitor.visit);
    MemberOrderingReporter(
      membersInfo: declarationVisitor.membersInfo,
      rule: _rule,
    ).report(
      declarationVisitor.membersInfo,
      alphabetize: _parameters.alphabetize,
      alphabetizeByType: _parameters.alphabetizeByType,
    );
  }
}

// MIT License
//
// Copyright (c) 2020-2021 Dart Code Checker team
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import 'package:analyzer/error/error.dart';
import 'package:solid_lints/src/lints/member_ordering/member_ordering_rule.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_info.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_order.dart';

class MemberOrderingReporter {
  final MemberOrderingRule _rule;
  final List<MemberInfo> _membersInfo;

  const MemberOrderingReporter({
    required List<MemberInfo> membersInfo,
    required MemberOrderingRule rule,
  }) : _membersInfo = membersInfo,
       _rule = rule;

  void report(
    List<MemberInfo> membersInfo, {
    required bool alphabetize,
    required bool alphabetizeByType,
  }) {
    _reportWrongOrder();
    if (alphabetize) {
      _reportAlphabeticalOrder();
    } else if (alphabetizeByType) {
      _reportAlphabeticalTypeOrder();
    }
  }

  void _reportWrongOrder() => _reportMembers(
    (order) => order.isWrong,
    MemberOrderingRule.wrongOrderCode,
    (order) => [
      order.memberGroup.toString(),
      order.previousMemberGroup?.toString() ?? '',
    ],
  );

  void _reportAlphabeticalOrder() => _reportMembers(
    (order) => order.isAlphabeticallyWrong,
    MemberOrderingRule.alphabeticalOrderCode,
    (order) => [
      order.memberNames.currentName,
      order.memberNames.previousName ?? '',
    ],
  );

  void _reportAlphabeticalTypeOrder() => _reportMembers(
    (order) => order.isByTypeWrong,
    MemberOrderingRule.alphabeticalByTypeOrderCode,
    (order) => [
      order.memberNames.currentTypeName,
      order.memberNames.previousTypeName ?? '',
    ],
  );

  void _reportMembers(
    bool Function(MemberOrder) filter,
    LintCode code,
    List<String> Function(MemberOrder) getArguments,
  ) {
    final filtered = _membersInfo.where((info) => filter(info.memberOrder));

    for (final memberInfo in filtered) {
      _rule.reportAtNode(
        memberInfo.classMember,
        diagnosticCode: code,
        arguments: getArguments(memberInfo.memberOrder),
      );
    }
  }
}

// MIT License
//
// Copyright (c) 2020-2021 Dart Code Checker team
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all
// copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.

import 'package:analyzer/dart/ast/ast.dart';
import 'package:analyzer/dart/ast/token.dart';
import 'package:collection/collection.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_group/constructor_member_group.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_group/field_member_group.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_group/get_set_member_group.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_group/member_group.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_group/method_member_group.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_info.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_names.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_order.dart';
import 'package:solid_lints/src/lints/member_ordering/models/member_ordering_parameters.dart';

class DeclarationOrderingVisitor {
  final bool _isFlutterWidget;
  final MemberOrderingParameters _parameters;

  final membersInfo = <MemberInfo>[];

  DeclarationOrderingVisitor({
    required MemberOrderingParameters parameters,
    required bool isFlutterWidget,
  }) : _parameters = parameters,
       _isFlutterWidget = isFlutterWidget;

  void visit(ClassMember member) => switch (member) {
    FieldDeclaration() => _visitFieldDeclaration(member),
    ConstructorDeclaration() => _visitConstructorDeclaration(member),
    MethodDeclaration() => _visitMethodDeclaration(member),
    _ => (),
  };

  void _visitFieldDeclaration(FieldDeclaration declaration) => _addMemberInfo(
    classMember: declaration,
    parsedGroup: FieldMemberGroup.parse(declaration),
    token: declaration.fields.variables.first.name,
    type: declaration.fields.type?.type?.getDisplayString() ?? '_',
  );

  void _visitConstructorDeclaration(ConstructorDeclaration declaration) =>
      _addMemberInfo(
        classMember: declaration,
        parsedGroup: ConstructorMemberGroup.parse(declaration),
        token: declaration.name,
        type: declaration.typeName?.name ?? '',
      );

  void _visitMethodDeclaration(MethodDeclaration declaration) {
    final group = (declaration.isGetter || declaration.isSetter)
        ? GetSetMemberGroup.parse(declaration)
        : MethodMemberGroup.parse(declaration);

    _addMemberInfo(
      classMember: declaration,
      parsedGroup: group,
      token: declaration.name,
      type: declaration.returnType?.type?.getDisplayString() ?? '_',
    );
  }

  void _addMemberInfo({
    required ClassMember classMember,
    required MemberGroup parsedGroup,
    required Token? token,
    required String type,
  }) {
    final closestGroup = _getClosestGroup(parsedGroup);
    if (closestGroup == null) return;

    membersInfo.add(
      MemberInfo(
        classMember: classMember,
        memberOrder: _getOrder(
          closestGroup,
          token?.lexeme ?? '',
          type,
        ),
      ),
    );
  }

  MemberGroup? _getClosestGroup(MemberGroup parsedGroup) {
    final closestGroups =
        (_isFlutterWidget
                ? _parameters.widgetsGroupsOrder
                : _parameters.groupsOrder)
            .where((group) => group.implies(parsedGroup))
            .sorted(
              (a, b) => b.getSortingCoefficient() - a.getSortingCoefficient(),
            );

    return closestGroups.firstOrNull;
  }

  MemberOrder _getOrder(
    MemberGroup memberGroup,
    String memberName,
    String typeName,
  ) {
    if (membersInfo.isEmpty) {
      return MemberOrder(
        memberNames: MemberNames(
          currentName: memberName,
          currentTypeName: typeName,
        ),
        isAlphabeticallyWrong: false,
        isByTypeWrong: false,
        memberGroup: memberGroup,
        isWrong: false,
      );
    }

    final lastMemberOrder = membersInfo.last.memberOrder;
    final hasSameGroup = lastMemberOrder.memberGroup == memberGroup;

    final previousMemberGroup =
        hasSameGroup && lastMemberOrder.previousMemberGroup != null
        ? lastMemberOrder.previousMemberGroup
        : lastMemberOrder.memberGroup;

    final memberNames = MemberNames(
      currentName: memberName,
      previousName: lastMemberOrder.memberNames.currentName,
      currentTypeName: typeName,
      previousTypeName: lastMemberOrder.memberNames.currentTypeName,
    );

    return MemberOrder(
      memberNames: memberNames,
      isAlphabeticallyWrong:
          hasSameGroup &&
          memberNames.currentName.compareTo(memberNames.previousName!) < 0,
      isByTypeWrong:
          hasSameGroup &&
          memberNames.currentTypeName.toLowerCase().compareTo(
                memberNames.previousTypeName!.toLowerCase(),
              ) <
              0,
      memberGroup: memberGroup,
      previousMemberGroup: previousMemberGroup,
      isWrong:
          (hasSameGroup && lastMemberOrder.isWrong) ||
          _isCurrentGroupBefore(
            lastMemberOrder.memberGroup,
            memberGroup,
          ),
    );
  }

  bool _isCurrentGroupBefore(
    MemberGroup lastMemberGroup,
    MemberGroup memberGroup,
  ) {
    final group = _isFlutterWidget
        ? _parameters.widgetsGroupsOrder
        : _parameters.groupsOrder;

    return group.indexOf(lastMemberGroup) > group.indexOf(memberGroup);
  }
}