These changes support arbitrary combinations of input + plain types
within a schema. Handling plain types at the property level was not
sufficient to support such combinations. Reifying these types
required updating quite a bit of code. This is likely to have caused
some temporary complications, but should eventually lead to
substantial simplification in the SDK and program code generators.
With the new design, input and optional types are explicit in the schema
type system. Optionals will only appear at the outermost level of a type
(i.e. Input<Optional<>>, Array<Optional<>>, etc. will not occur). In
addition to explicit input types, each object type now has a "plain"
shape and an "input" shape. The former uses only plain types; the latter
uses input shapes wherever a plain type is not specified. Plain types
are indicated in the schema by setting the "plain" property of a type spec
to true.
Specifically, handle index and relative traversal expressions, and clean
up the code a little bit.
This should also help us pick up more `pulumi.interpolate` calls in TS.
Some property names are mapped from their `camelCase` Pulumi name to a
`snake_case` Python name. This mapping is irregular, and only occurs for
resources properties and function calls.
Note that there's still more work to do here: this only fixes names on
the output side; the input side is still broken for nested resource
proprerties and function calls.
The underlying design--annotated types in `hcl2/model`--may need some
additional work in the future, but I _believe_ it's good enough for now.
