quasilyte/astnorm

AST normalization experiment

I worked on NoVerify static analyzer for PHP and KPHP compiler at vk.com. Before that, I was a part of Intel Go team: I added AVX-512 support and some compiler optimizations there, but most of the time I was tinkering the Go x86-64 assembler.

I try to maintain several^[1] good^[2] static^[3] analyzers^[4].
Sometimes I create dev tools like phpgrep (structural PHP code search using AST patterns).

Some facts about me:

• I do not approve the ways of Russia government (wars, crazy mass propaganda, censorship, ...) ⬜️🟦⬜️
• I enjoy 3D-printing and drawing
• I love video games and game development
• My tech talks and articles can be found at github.com/quasilyte/talks
• Co-host of the GolangKazan Go community
• You can call me Alex

astnorm's Issues

Perform unslice for s[:] where s is a slice or a string

AST matching with patterns

Check whether gogrep can be used as a library now for code matching purposes

If yes, use it instead of doing a lot of routine comparisons manually.
Otherwise, write such a library and use it.

rewrite for/range loops `_, _ =`

- for _, _ = range expr {}
+ for range expr {}

Figure out how to handle types info invalidation

If we map expr->expr, types info provided via *types.Info will not return anything for newly generated AST. Some kind of a workaround is required.

readme: add normalized code examples

Replace type aliases in AST

Split assignments / defs

Where possible, split single-value context assignments.

- var x, y = 1, 2
+ var x = 1
+ var y = 2

This makes handling assignments a little bit easier.

Don't break numeric conversions

This code:

x := uint32(0)

Turned into:

x := 0

That is incorrect.
Should be fixed.

cmd/go-normalize: don't strip comments?

For now, we're stripping comments to make things easier.
If there is a need to keep comments, this issue is the right place to lead that discussion.

cmd/go-normalize: support package targets

Single file targets are not even remotely enough.
At the very least it should accept single package specifier.

Add tests that check for normalized code correctness

The simplest way is:

1. Have a set of selected packages. Go stdlib is OK.
2. Normalize all packages from it.
3. Verify that all tests of those pacakges still pass and build is not broken.

rewrite if/else to a switch

Before:

if a {
} else if b {
}

After:

switch {
case a:
case b:
}