Another incremental change to diagnostic formatting. I simply recurse
over all the tokens in the subtree of a parse node and construct a
`DiagnosticLocation` that covers all of the tokens.
I believe it's nicer for the user to be directed at the entire chunk of
source where the error is occurring rather then just pointing at the
bracketing/terminator tokens, but let me know if you all agree.
This creates a namespace for `package` scope.
It looks like names of class_decls in namespaces lead to an unexpected
instref. This is already true, as best as I can tell. I'm not sure if
there's a preferred approach to address that, so I've left a TODO for
now.
This removes the filename from the file-scoped block, and places it
above to make it clear where the full SemIR begins (with multifile,
providing a barrier between).
This is an incremental improvement on our diagnostic messages that
simply underlines an entire token if the token is larger than 1 char
(else it points to the single char with a caret like it used to).
Add a `NameId` that is effectively just a wrapper around a `StringId`,
with
some additional predefined values for names that don't correspond to
strings, such as the name of `self` or the function's return slot.
This replaces the use of `VarStorage` in this case.
Add an `UnboundFieldType` type as the type of a field, in cases where
it's referenced without an accompanying object.
Add a `BindName` node to describe the name binding performed for both
variables and fields so that we can handle them more uniformly.
Retain the `ClassDeclaration` node to represent a syntactic declaration
of a class (including possibly a declaration of a generic class), but
use a separate SemIR node to represent the class type itself. This
allows us to give the two separate treatment.
The `ClassDeclaration` is still entered into the name lookup table for
its enclosing scope, but when it is named in an expression, the class
type is produced instead. When the class declaration is named in a
declaration name, it can be used to define members of the class, but an
expression that resolves to the class type cannot be used to define
members of the class.
In order to distinguish these cases, use `Name` rather than
`NameExpression` for the left-hand side of a `QualifiedName` parse node.
This removes the only use of the `Expression` form of a declaration
name, so that is also removed.
In the future, `ClassType` will also be used to describe types such as
`Vector(T)`, for which there is no corresponding `ClassDeclaration`.
This includes being able to define a class that was previously
forward-declared, and being able to define a member function out-of-line
that was previously declared inside a class.
No support for fields or methods yet, and a class definition doesn't yet
cause the class to be treated as a complete type.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Incomplete types may be nested within other types; for example, a tuple
type might have an incomplete type as an element. Handle such cases by
walking through nested incomplete types when completing a type. This is
done non-recursively in case a very complex type is formed.
Types are generally no longer completed at the point where they're
formed. Instead, we attempt to complete a type when it is used in a
context that requires a complete type, and diagnose if the type cannot
be completed at that point. This will be necessary for classes, which
can become complete after their first use, and helps tease out bugs
where a type completeness check is missing.