Summary of front end code review issues at the annual code rollover site



Ali Mei guide.

* Review in the technical team of the engineer culture construction is very meaningful, it is the most effective way to form a unified team style, the author of his own team in a year of CR common small problems to do some combing, I hope to help you a little. I. Introduction.

The team has carried out offline weekly reviews for more than a year, as the main judges, I originally thought that it would take a lot of time and effort to give ** suggestions, and always thought that it would be of great help to the reviewees to improve the ** design problems, but in fact, the review found that most of the students were still in some basic ** quality problems, and the review to improve the design or find business bugs to achieve the goal rarely appeared, so I think the team should still have enough patience for CR. Explain the basic problems as a bug and accumulate them on the way to excellent engineering. At the same time, I can also deeply feel that each student's attitude towards ** is different, which has produced two differentiations, some people will improve very quickly, and some people will continue to repeat the problems that have been reviewed. I hope it can be of little help to everyone. Second, the rollover scene (common problems in CR).

2.1 **Normative class

2.1.1 Use manaRollover Index:Description:Mana represents a value that is not declared in ** and is used directly, which is widespread in our ** review questions.

bad case

const now = date.now();const lastvisittime = localstorage.getitem('last_visit_time');

if (lastvisittime &&parseint(lastvisittime, 10) >24 * 60 * 60 * 1000)

localstorage.setitem('last_visit_time', now.tostring())

const last_visit_time_cache_key = 'last_visit_time';const day_in_ms = 24 * 60 * 60 * 1000;

const now = date.now();const lastvisittime = localstorage.getitem(last_visit_time_cache_key);

if (lastvisittime &&parseint(lastvisittime, 10) >day_in_ms)

localstorage.setitem(last_visit_time_cache_key, now.tostring())

2.1.3 Using Ghost DependenciesRollover Index:Description:Ghost dependencies (also known as implicit dependencies or implicit dependencies) are packages that are not in a module of the project that are not in that moduleDependencies declared directly in the JSON file.

2.1.4 The no-else-return principle is not followedRollover Index:Description:no-else-return is a quality rule that emphasizes brevity and readability, and is used to indicate that there is no need to use an else block when an if block already contains a return statement. Because the return statement in the if block exits the current function as soon as the return statement in the if block is executed, else is redundant. ❌ you can skip the else block

function hello(condition: boolean) else

function hello(condition: boolean)

return '