Chore: fix the timing to define rules for tests

[mysticatea]

What is the purpose of this pull request? (put an "X" next to item)

[X] Other, please explain:

What changes did you make? (Give an overview)

This PR changes the timing to define rules for tests.

Because tests/lib/rules.js resets rules in beforeEach handler, RuleTester.define does not work the following case.

$ mocha "tests/lib/rules.js" "tests/lib/rules/no-unused-vars.js" --reporter progress

Result:

 [▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬]

  207 passing (888ms)
  3 failing

  1) no-unused-vars valid /*eslint use-every-a:1*/ var a;:
     Error: undefined line 1:
        Configuration for rule "use-every-a" is invalid:
Cannot read property 'meta' of undefined
      at Object.validateRuleOptions (C:\Users\starc\Documents\GitHub\eslint\lib\config\config-validator.js:109:15)
      at Object.keys.forEach.name (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:368:39)
      at Array.forEach (native)
      at ast.comments.forEach.comment (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:365:44)
      at Array.forEach (native)
      at modifyConfigsFromComments (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:331:18)
      at EventEmitter.module.exports.api.verify (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:833:26)
      at runRuleForItem (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:380:38)
      at testValidTemplate (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:413:28)
      at Context.RuleTester.it (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:511:25)
      at callFn (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:326:21)
      at Test.Runnable.run (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:319:7)
      at Runner.runTest (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:422:10)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:528:12
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:342:14)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:352:7
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:284:14)
      at Immediate._onImmediate (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:320:5)

  2) no-unused-vars valid /*eslint use-every-a:1*/ !function(a) { return 1; }:
     Error: undefined line 1:
        Configuration for rule "use-every-a" is invalid:
Cannot read property 'meta' of undefined
      at Object.validateRuleOptions (C:\Users\starc\Documents\GitHub\eslint\lib\config\config-validator.js:109:15)
      at Object.keys.forEach.name (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:368:39)
      at Array.forEach (native)
      at ast.comments.forEach.comment (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:365:44)
      at Array.forEach (native)
      at modifyConfigsFromComments (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:331:18)
      at EventEmitter.module.exports.api.verify (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:833:26)
      at runRuleForItem (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:380:38)
      at testValidTemplate (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:413:28)
      at Context.RuleTester.it (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:511:25)
      at callFn (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:326:21)
      at Test.Runnable.run (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:319:7)
      at Runner.runTest (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:422:10)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:528:12
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:342:14)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:352:7
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:284:14)
      at Immediate._onImmediate (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:320:5)

  3) no-unused-vars valid /*eslint use-every-a:1*/ !function() { var a; return 1 }:
     Error: undefined line 1:
        Configuration for rule "use-every-a" is invalid:
Cannot read property 'meta' of undefined
      at Object.validateRuleOptions (C:\Users\starc\Documents\GitHub\eslint\lib\config\config-validator.js:109:15)
      at Object.keys.forEach.name (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:368:39)
      at Array.forEach (native)
      at ast.comments.forEach.comment (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:365:44)
      at Array.forEach (native)
      at modifyConfigsFromComments (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:331:18)
      at EventEmitter.module.exports.api.verify (C:\Users\starc\Documents\GitHub\eslint\lib\eslint.js:833:26)
      at runRuleForItem (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:380:38)
      at testValidTemplate (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:413:28)
      at Context.RuleTester.it (C:\Users\starc\Documents\GitHub\eslint\lib\testers\rule-tester.js:511:25)
      at callFn (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:326:21)
      at Test.Runnable.run (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runnable.js:319:7)
      at Runner.runTest (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:422:10)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:528:12
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:342:14)
      at C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:352:7
      at next (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:284:14)
      at Immediate._onImmediate (C:\Users\starc\nodist\bin\node_modules\mocha\lib\runner.js:320:5)

.

1. tests/lib/rules/no-unused-vars.js defines use-every-a rule on the top.
2. tests/lib/rules.js set the beforeEach handler to reset rules.
3. It runs the beforeEach handler, then it removes use-every-a rule.
4. The testcases of tests/lib/rules/no-unused-vars.js use use-every-a rule, but it's not defined.

So this PR moves the timing which defines rules to "before each test".

Is there anything you'd like reviewers to focus on?

Nothing in particular.

[mention-bot]

@mysticatea, thanks for your PR! By analyzing the history of the files in this pull request, we identified @nzakas, @platinumazure and @gyandeeps to be potential reviewers.

[eslintbot]

LGTM