Correct standalone test environment variable

[fisker]

refs:

• old azure pipeline settings
• mistake

• I’ve added tests to confirm my change works.
• (If changing the API or CLI) I’ve documented the changes I’ve made (in the docs/ directory)
• (If the change is user-facing) I’ve added my changes to changelog_unreleased/*/pr-XXXX.md file following changelog_unreleased/TEMPLATE.md.
• I’ve read the contributing guidelines.

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[fisker]

How do I know it's correct or not? I guess have to check locally.

[thorn0]

How do I know it's correct or not? I guess have to check locally.

One way is to add a test that standalone doesn't have methods like getFileInfo and clearConfigCache.

[fisker]

Problem is I don't even know if it's running standalone test.

[thorn0]

Right. So we can add a test that would check that prettier.getFileInfo should be undefined if and only if this env variable is set.

[fisker]

But if I set the variable name wrong again, jest will run the default tests, still get pass.

[thorn0]

The default test should assert the opposite: prettier.getFileInfo should be defined.

[thorn0]

Also we could add some kind of report to which each test run would add something (only on CI) and in the end a separate step will check that this report is correct.