check-was-shown-methods.ts

// Copyright 2020 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import {createRule} from './utils/ruleCreator.ts';

export default createRule({
  name: 'check-was-shown-methods',
  meta: {
    type: 'problem',
    docs: {
      description: 'Checks wasShown() method definitions call super.wasShown();',
      category: 'Possible Errors',
    },
    messages: {
      superFirstCall: 'Please make sure the first call in wasShown is to super.wasShown().',
    },
    fixable: 'code',
    schema: [],  // no options
  },
  defaultOptions: [],
  create: function(context) {
    return {
      MethodDefinition(node) {
        if (node.key.type !== 'Identifier') {
          return;
        }

        const nodeName = node.key.name;
        if (nodeName !== 'wasShown') {
          return;
        }

        const ancestorClass = node.parent.parent;
        if (ancestorClass.type !== 'ClassDeclaration') {
          return;
        }
        if (ancestorClass.superClass?.type === 'MemberExpression' &&
            ancestorClass.superClass.property.type === 'Identifier' &&
            ancestorClass.superClass.property.name === 'Widget') {
          const topBodyNode = node.value.body?.body[0];
          if (!topBodyNode) {
            return;
          }

          if (!(topBodyNode.type === 'ExpressionStatement' && topBodyNode.expression.type === 'CallExpression' &&
                topBodyNode.expression.callee.type === 'MemberExpression' &&
                topBodyNode.expression.callee.object.type === 'Super' &&
                topBodyNode.expression.callee.property.type === 'Identifier' &&
                topBodyNode.expression.callee.property.name === 'wasShown')) {
            context.report({node, messageId: 'superFirstCall'});
          }
        }
      },
    };
  },
});