test(client): add e2e reload client tests

[knagaitsev]

• This is a bugfix
• This is a feature
• This is a code refactor
• This is a test update
• This is a docs update
• This is a metadata update

For Bugs and Features; did you add new tests?

N/A

Motivation / Use-Case

#1933

More tests are needed for the client. These tests confirm that reloading in the browser is working.

Breaking Changes

Sometimes reload took long to occur, so I set a long wait time of 10000. I think this was fixed after I set poll: 500.

Also note that I added a temp directory in the testing directory so that my tests can write to files for reload simulation

Additional Info

Things that can still be added onto this:

• Intercept the sockjs communications to confirm all the messages pass as expected
• Check the console output to make sure everything is working
• Test cases where there should be errors. For example, set hotOnly: true then do something that cannot be reloaded with hot and see the error in the console, or shut off the server early and make sure the console says WDS Disconnected

EDIT:
Another use case for this method

• Check that the client successfully gets hot-update.json

[codecov]

Codecov Report

Merging #1940 into master will increase coverage by 0.11%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1940      +/-   ##
==========================================
+ Coverage   91.13%   91.25%   +0.11%     
==========================================
  Files          18       18              
  Lines         835      835              
  Branches      262      262              
==========================================
+ Hits          761      762       +1     
+ Misses         70       69       -1     
  Partials        4        4

Impacted Files	Coverage Δ
lib/Server.js	91.77% <0%> (+0.22%)	⬆️

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[codecov]

Codecov Report

Merging #1940 into master will increase coverage by 0.44%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1940      +/-   ##
==========================================
+ Coverage    91.8%   92.24%   +0.44%     
==========================================
  Files          23       23              
  Lines         903      903              
  Branches      283      283              
==========================================
+ Hits          829      833       +4     
+ Misses         71       67       -4     
  Partials        3        3

Impacted Files	Coverage Δ
lib/Server.js	92.74% <0%> (+0.43%)	⬆️
lib/servers/SockJSServer.js	96.29% <0%> (+7.4%)	⬆️

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[alexander-akait]

Great job!

Some notes:

1. Let's create test_e2e directory in root
2. Rename ClientReload.test.js to Client.test.js
3. Maybe move other e2e test to this directory

[alexander-akait]

Also need fix linting problem

[knagaitsev]

@evilebottnawi What should I name the other e2e test if I move it into the same directory? Maybe ClientOptions.test.js since it confirms that the options work on the client?

[alexander-akait]

Sounds good

[knagaitsev]

@evilebottnawi Why not test/e2e/? May be misleading if some tests are not in the test directory

[knagaitsev]

I made the test/e2e change, I can switch it if you disagree.

[alexander-akait]

👍 We can refactor tests in any time, just want keep e2e test separate from unit tests, same for integration tests we should do, but not in this PR, let's do it future

[hiroppy]

Did you use editorconfig?

[knagaitsev]

What does that mean? I'm not sure what editorconfig does. Is there something wrong with doing this?

[hiroppy]

I'm not sure but only this file has EoF icon. see https://github.com/webpack/webpack-dev-server/blob/master/.editorconfig#L7

[knagaitsev]

Oh I see. I saw that too but overlooked it earlier. I think the file just needs another line at the end.

[alexander-akait]

/cc @hiroppy

[alexander-akait]

What is wrong with azure 😕 :

[alexander-akait]

Good job!