[Test] vitest migration issues

[jeremymeng]

This issue documents obstacles in migrating to vitest in our repo.

• @types/chai conflicts @types/chai conflict with @vitest/expect/dist/chai.d.cts vitest-dev/vitest#4688

../../node_modules/@types/chai/index.d.ts:1:1 - error TS6200: Definitions of the following identifiers conflict with those in another file: Message, ObjectProperty, ChaiPlugin, AssertionArgs, Operator, OperatorComparable, AssertionError, chai

• vitest has cobertura report but our config doesn't enable it. We should replace the json reporter with cobertura, and add --coverage command line option to run test with code coverage

Node

Browser

• We use an envProcessor plugin in Karma tests to inject environment variables to browser tests
• module mocking in browser not implemented yet Implement module mocking in browser mode vitest-dev/vitest#3046
• util dependency causes problem in tests.
• we had to use verbatimModuleSyntax: true and add type to imports. However, it is not clear yet how we could make the export * from "./models" pattern work. We use this pattern a lot in codegen.

SyntaxError: The requested module '/src/generated/src/index.ts' does not provide an export named 'ConfigurationSnapshot'

[xirzec]

the main tsc problem seems to be chai globals conflicting with the bundled version of chai that vitest provides

[xirzec]

for environment variables I think we can use vite config for this: https://vitejs.dev/config/#using-environment-variables-in-config

[xirzec]

/cc @mpodwysocki

[jeremymeng]

for environment variables I think we can use vite config for this: https://vitejs.dev/config/#using-environment-variables-in-config

yes, looking into that

[jeremymeng]

/cc @maorleger