This fixes `IfConfigDecl` for both the AST printer and control flow
libraries.
It turns out that the active lements of an `IfConfigDecl` are already
listed in the enclosing scope (like a `BraceStmt`), so they should not
be listed as children, and `IfConfigDecl` can be jsut a leaf in the
control flow.
In order to distinguish overloads of the constructor and for consistency
with other function calls, `ConstructorDecl` string representation uses
the name which includes parentheses and parameter labels.
For consistency also the destructor got the same change, which means
all `DestructorDecl`s will now show as `deinit()` rather than `deinit`.
By explicitly marking children in the `schema.yml` file, an internal
`getAChild` predicate is implemented, that is in turn used in `AstNode`
to implement `getParent`.
This is yet to be used in the control flow library to replace the
hand-rolled implementation.
A further, more complex step is to use the same information to fully
generate the core implementation of `PrintAst` (including the
accessor string). This will be done later.
The `parent` tests use the same swift code as the extractor tests, and
this is currently enforced by `sync-files.py`. Notice that `qltest.sh`
had to be modified to deal with multiple files, which was not working
yet.
This transfers the current state of `StmtVisitor` in the PoC, plus some
changes required for the update to swift 5.6.
Also `getLabel` in `SwiftDispatcher` got renamed to `createLabel`, and
is now correctly outputting the label assignment to the trap file.
This transfers the current state of `DeclVisitor` from the
proof-of-concept.
TODO: make the `declarations` tests in `extractor-tests` more
comprehensive.
