Summary:
I want to better understand the bugs we have in abstract evaluation. One of my ideas to do this is to replace all the literals in test262 tests with abstract values and see what our test coverage is. The first step to do this is to serialize the test262 sources after running them in Prepack and checking if their generated JavaScript runs correctly. This PR does that by adding a `--serializer` flag.
With my methodology, all test262 harnesses are serialized every time since they are in the global scope. This unfortunately seems to be unavoidable since doing otherwise would change program semantics and break the tests.
Running `time yarn test-test262` takes about 2 minutes and has a 98% pass rate. Running `time yarn test-test262 --serializer` takes about 5 minutes and has a 95% pass rate. [Here’s a diff of the two results.](https://gist.github.com/calebmer/1c9fe396b63ba055458c599c2be18a58)
[Here is a selection of some of the bugs](https://gist.github.com/calebmer/1ac381096a4aa7be1fc7dc2163276ab4) in the serializer caught by running test262 with the Prepack serializer. I might open issues for these, but they can be a bit pedantic. I might fix some of them depending on how important they are to the React code we want to compile.
Notably we have:
- Lots of invariants being triggered. I particularly saw [a lot of this invariant](7d355ef4c5/src/serializer/ResidualHeapVisitor.js (L531)). (An example of this is [`07.md`](https://gist.github.com/calebmer/1ac381096a4aa7be1fc7dc2163276ab4#file-07-md).)
- Lots of values that are visited, but not serialized. (An example of this is [`01.md`](https://gist.github.com/calebmer/1ac381096a4aa7be1fc7dc2163276ab4#file-01-md).)
- Some incorrect outputs only caught by executing code. Could not be caught by static analysis. Particularly around class serialization.
I’ll build off this PR to get coverage for the abstract evaluator next, but I found these results interesting on their own so decided to do this in two PRs.
Pull Request resolved: https://github.com/facebook/prepack/pull/2290
Differential Revision: D8908479
Pulled By: calebmer
fbshipit-source-id: aa57d47611fbd92af33e4647fed7bf7990fb6de1
Summary:
Release notes: upgrades Prepack to use Babel 7.0.0-beta.53
This is a big PR that updates all of Prepack to Babel 7. Babylon is now `babel/parser` and pretty much all of the the previous Babel packages are now located in scoped packages. I had to make a bunch of changes around Jest/Flow/Webpack to get this all working. The build times of building Prepack itself seem considerably faster (easily twice as fast locally). I followed most of the Babel 6 -> 7 upgrade guide from the Babel site in terms of changing nodes and type definitions to match the new ones.
Pull Request resolved: https://github.com/facebook/prepack/pull/2256
Differential Revision: D8850583
Pulled By: trueadm
fbshipit-source-id: 2d2aaec25c6a1ccd1ec0c08c5e7e2a71f78ac2d8
