SetEnv() and SetEnvs()

[elliotchance]

SetEnv sets an environment variable and returns a reset function to ensure the environment is always returned to it's previous state:

resetEnv := tf.SetEnv(t, "HOME", "/somewhere/else")
defer resetEnv()

If you would like to set multiple environment variables, you can use SetEnvs in the same way:

resetEnv := tf.SetEnvs(t, map[string]string{
    "HOME":  "/somewhere/else",
    "DEBUG": "on",
})
defer resetEnv()

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