Deep-clones all `Node`s and `Type`s into a new module.
Instead of writing a million standalone tests that'll only ever test the
existing fields of each type, I've opted to write the tests using
wgsl<->ast<->wgsl conversion. This means the tests require the enabling
of TINT_BUILD_WGSL_READER and TINT_BUILD_WGSL_WRITER, but I believe this
is much easier to maintain.
I'm aware there are probably gaps in the tests, and that even full
coverage is likely to rapidly rot, so I've also added
fuzzers/tint_ast_clone_fuzzer.cc - a fuzzer based test that ensures that
all AST modules can be cloned with identical reproduction.
I've run this across 100 cores of a 3990x for 4 hours, fixing the
single issue it detected.
Note: Expressions do not currently clone their `TypeManager` determined
types. This is for two reasons:
(a) This initial CL is mahoosive enough.
(b) I'm uncertain whether we actually want to clone this info, or to
re-run the `TypeDeterminer` after each AST transform. Maybe it should
be optional. Time will tell.
Fixed: tint:307
Change-Id: Id90fab06aaa740c805d12b66f3f11d1f452c6805
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/33300
Commit-Queue: Ben Clayton <bclayton@google.com>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
Reviewed-by: David Neto <dneto@google.com>