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.
These changes fix a regression introduced by #6686 that caused the SDK
code generators for .NET, Python, and Typescript to omit definitions for
plain object types. This regression occurred because #6686 drew a
clearer line between types used as resource arguments and types used
as function arguments, but conflated "resource arguments" with "inputty
types". This caused the code generators to generate inputty types for
any types used as resource arguments, even those that are used for
plainly-typed properties.
Fixes#6796.
