When we originally introduced this environment variable it was intended to
solve for the use-case where a particular invocation of Terraform needs
a different CLI configuration than usual, such as if Terraform is being
run as part of an automated test suite or other sort of automated
situation with different needs than normal use.
However, we accidentally had it only override the original singleton CLI
config file, while leaving the CLI configuration directory still enabled.
Now we'll take the CLI configuration out of the equation too, so that only
the single specified configuration file and any other environment-sourced
settings will be included.
This new CLI config block type allows explicitly specifying where
Terraform should look to find provider plugins for installation. This is
not used anywhere as of this commit, but in a future commit we'll change
package main to treat the presence of a block of this type as a request
to disable the default set of provider sources and use these explicitly-
specified ones instead.
A more convenient interface to get a throwaway empty credentials source
for use in tests, which doesn't interact at all with the real CLI
configuration directory.
This was a leftover from the migration of these types from the main
package, but we don't actually need or want this here because this
particular detail is still handled by the main package, and because the
cliconfig package must not depend on the command package in order to avoid
an import cycle.
This new implementation is not yet used, but should eventually replace the
technique of composing together various types from the svchost/auth
package, since our requirements are now complex enough that they're more
straightforward to express in direct code within a single type than as
a composition of the building blocks in the svchost/auth package.
This is just a wholesale move of the CLI configuration types and functions
from the main package into its own package, leaving behind some type
aliases and wrappers for now to keep existing callers working.
This commit alone doesn't really achieve anything, but in future commits
we'll expand the functionality in this package.
