When passing a bool type to a variable such as `-var foo=true`, the CLI
would parse this as a `bool` type which Terraform core cannot handle.
It would then error with an invalid type error.
This changes the handling to convert the bool to its literally string
value given on the command-line.
When we parse a map from HCL, it's decoded into a list of maps because
HCL allows declaring a key multiple times to implicitly add it to a
list. Since there's no terraform variable configuration that supports
this structure, we can always flatten a []map[string]interface{} value
to a map[string]interface{} and remove any type rrors trying to apply
that value.
Don't try to parse a varibale as HCL if the value can be parse as a
single number. HCL will always attempt to convert the value to a number,
even if we later find the configured variable's type to be a string.
Terraform 0.7 introduces lists and maps as first-class values for
variables, in addition to string values which were previously available.
However, there was previously no way to override the default value of a
list or map, and the functionality for overriding specific map keys was
broken.
Using the environment variable method for setting variable values, there
was previously no way to give a variable a value of a list or map. These
now support HCL for individual values - specifying:
TF_VAR_test='["Hello", "World"]'
will set the variable `test` to a two-element list containing "Hello"
and "World". Specifying
TF_VAR_test_map='{"Hello = "World", "Foo" = "bar"}'
will set the variable `test_map` to a two-element map with keys "Hello"
and "Foo", and values "World" and "bar" respectively.
The same logic is applied to `-var` flags, and the file parsed by
`-var-files` ("autoVariables").
Note that care must be taken to not run into shell expansion for `-var-`
flags and environment variables.
We also merge map keys where appropriate. The override syntax has
changed (to be noted in CHANGELOG as a breaking change), so several
tests needed their syntax updating from the old `amis.us-east-1 =
"newValue"` style to `amis = "{ "us-east-1" = "newValue"}"` style as
defined in TF-002.
In order to continue supporting the `-var "foo=bar"` type of variable
flag (which is not valid HCL), a special case error is checked after HCL
parsing fails, and the old code path runs instead.
