lib/src/rules/library_prefixes.dart

// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:analyzer/dart/ast/ast.dart';
import 'package:analyzer/dart/ast/visitor.dart';

import '../analyzer.dart';
import '../utils.dart';

const _desc =
    r'Use `lowercase_with_underscores` when specifying a library prefix.';

const _details = r'''
**DO** use `lowercase_with_underscores` when specifying a library prefix.

**BAD:**
```dart
import 'dart:math' as Math;
import 'dart:json' as JSON;
import 'package:js/js.dart' as JS;
import 'package:javascript_utils/javascript_utils.dart' as jsUtils;
```

**GOOD:**
```dart
import 'dart:math' as math;
import 'dart:json' as json;
import 'package:js/js.dart' as js;
import 'package:javascript_utils/javascript_utils.dart' as js_utils;
```

''';

class LibraryPrefixes extends LintRule {
  static const LintCode code = LintCode(
      'library_prefixes', "The prefix '{0}' isn't a snake_case identifier.",
      correctionMessage:
          'Try changing the prefix to follow the snake_case style.');

  LibraryPrefixes()
      : super(
            name: 'library_prefixes',
            description: _desc,
            details: _details,
            group: Group.style);

  @override
  LintCode get lintCode => code;

  @override
  void registerNodeProcessors(
      NodeLintRegistry registry, LinterContext context) {
    var visitor = _Visitor(this);
    registry.addImportDirective(this, visitor);
  }
}

class _Visitor extends SimpleAstVisitor<void> {
  final LintRule rule;

  _Visitor(this.rule);

  @override
  void visitImportDirective(ImportDirective node) {
    var prefix = node.prefix;
    if (prefix != null && !isValidLibraryPrefix(prefix.toString())) {
      rule.reportLint(prefix, arguments: [prefix.toString()]);
    }
  }
}