OAuth2 is a specification that defines several ways to handle authentication and authorization.

It is quite an extensive specification and covers several complex use cases.

It includes ways to authenticate using a "third party".

That's what all the systems with "login with Facebook, Google, Twitter, GitHub" use underneath.

### OAuth 1

                tmpTestFiles.keys
            )
            cleanUp(tmpTestFiles.keys)
            projectPathToLeftoverFiles[projectPath] = tmpTestFiles
        }

        // Third run: verify and throw exceptions
        val exceptions = mutableListOf<Exception>()
        parameters.projectStates.get()
            .filter { projectPathToLeftoverFiles.containsKey(it.key) }

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