4 ms·

Show HN: Locust – “Git diff” over abstract syntax trees

26 points by zomglings 6y ago

shad0wfax 6y ago
Nice!
smilliken 6y ago
I can't wait until the future when we have version control at the AST level instead of using text files. I've learned only recently about the `git log -L` flag that allows you to view version history for a specific function in a specific file. But the feature will look incredibly weak in retrospect when we're able to view history of AST structures across files and renames.
- zomglings 6y ago
  "git log -L" is magic. :) It does take a long time to run - will have to dig into the git source code to see what it's doing under the hood.
davidbuniat 6y ago
We have been an early adopter at https://github.com/activeloopai/Hub https://github.com/activeloopai/Hub. It helped me to quickly review large PRs that otherwise took us long time to understands the high-level picture.
hbt 6y ago
I've been thinking about a similar tool in go that would use the call graph it would show how many new/changed calls were made and also include basic info about new declarations it would give a quick overview of changes and hidden side effects prior to commits thanks to go static analysis
- zomglings 6y ago
  This is a really nice idea. Have been thinking of something similar. Building a call graph using a static analyzer is quite difficult for languages like Python where it can be difficult to resolve imports. Python programmers can even make imports inside if statements or override imports inside a function body. Would this be a lot easier in go? The case that scares me a bit in Go is implicit imports (e.g. importing a driver for use with `database/sql`). But maybe all that is very clear when doing static analysis? In go, do you think it would be a good approach to instrument the compiler to emit a call graph instead of using an AST traversal. By the way, I'm planning to extend the Locust output spec to include more than just definitions (e.g. TODOs, call dependencies, imports, etc.). Also tried to make it easy to use custom metadata extractors as part of the Locust pipeline. (Took a couple of hours to add the Javascript extractor.) Would love to collaborate with you on Go extraction, if you're interested?
  - hbt 6y ago
    Continued discussion here https://github.com/bugout-dev/locust/issues/39 https://github.com/bugout-dev/locust/issues/39 Cheers

26 points by zomglings 6y ago

Nice!

I can't wait until the future when we have version control at the AST level instead of using text files. I've learned only recently about the `git log -L` flag that allows you to view version history for a specific function in a specific file. But the feature will look incredibly weak in retrospect when we're able to view history of AST structures across files and renames.

zomglings 6y ago
"git log -L" is magic. :) It does take a long time to run - will have to dig into the git source code to see what it's doing under the hood.

davidbuniat 6y ago

We have been an early adopter at https://github.com/activeloopai/Hub https://github.com/activeloopai/Hub. It helped me to quickly review large PRs that otherwise took us long time to understands the high-level picture.

hbt 6y ago

I've been thinking about a similar tool in go that would use the call graph it would show how many new/changed calls were made and also include basic info about new declarations it would give a quick overview of changes and hidden side effects prior to commits thanks to go static analysis

zomglings 6y ago
This is a really nice idea. Have been thinking of something similar. Building a call graph using a static analyzer is quite difficult for languages like Python where it can be difficult to resolve imports. Python programmers can even make imports inside if statements or override imports inside a function body. Would this be a lot easier in go? The case that scares me a bit in Go is implicit imports (e.g. importing a driver for use with `database/sql`). But maybe all that is very clear when doing static analysis? In go, do you think it would be a good approach to instrument the compiler to emit a call graph instead of using an AST traversal. By the way, I'm planning to extend the Locust output spec to include more than just definitions (e.g. TODOs, call dependencies, imports, etc.). Also tried to make it easy to use custom metadata extractors as part of the Locust pipeline. (Took a couple of hours to add the Javascript extractor.) Would love to collaborate with you on Go extraction, if you're interested?
- hbt 6y ago
  Continued discussion here https://github.com/bugout-dev/locust/issues/39 https://github.com/bugout-dev/locust/issues/39 Cheers