https://github.com/etiennebacher/astgrepr
Parse and Manipulate R Code
https://github.com/etiennebacher/astgrepr
Last synced: 29 days ago
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Parse and Manipulate R Code
- Host: GitHub
- URL: https://github.com/etiennebacher/astgrepr
- Owner: etiennebacher
- License: other
- Created: 2024-03-01T17:46:53.000Z (about 1 year ago)
- Default Branch: main
- Last Pushed: 2025-02-12T15:23:13.000Z (2 months ago)
- Last Synced: 2025-03-15T00:51:58.261Z (about 1 month ago)
- Language: R
- Homepage: https://astgrepr.etiennebacher.com/
- Size: 70.8 MB
- Stars: 22
- Watchers: 1
- Forks: 2
- Open Issues: 5
-
Metadata Files:
- Readme: README.Rmd
- Changelog: NEWS.md
- License: LICENSE
Awesome Lists containing this project
- jimsghstars - etiennebacher/astgrepr - Parse and Manipulate R Code (R)
README
---
output: github_document
---
```{r, include = FALSE}
knitr::opts_chunk$set(
collapse = TRUE,
comment = "#>",
fig.path = "man/figures/README-",
out.width = "100%"
)
```
# astgrepr
[](https://github.com/etiennebacher/astgrepr/actions/workflows/R-CMD-check.yaml)
[](https://app.codecov.io/gh/etiennebacher/astgrepr?branch=main)
`astgrepr` provides R bindings to the [ast-grep](https://ast-grep.github.io/)
Rust crate. `ast-grep` is a tool to parse the abstract syntax tree (AST) of some
code and to perform search and rewrite of code. This is extremely useful to build
linters, stylers, and perform a lot of code analysis.
See the example below and the [“Getting started”
vignette](https://astgrepr.etiennebacher.com/articles/astgrepr) for
a gentle introduction to `astgrepr`.
Since `astgrepr` can be used as a low-level foundation for other tools (such as
linters), the number of R dependencies is kept low:
```r
> pak::local_deps_tree()
✔ Loading metadata database ... done
local::. 0.0.1 [new][bld]
├─checkmate 2.3.1 [new][dl] (746.54 kB)
│ └─backports 1.5.0 [new]
├─rrapply 1.2.7 [new]
└─yaml 2.3.8 [new][dl] (119.08 kB)
Key: [new] new | [dl] download | [bld] build
```
## Installation
``` r
install.packages('astgrepr', repos = c('https://etiennebacher.r-universe.dev', 'https://cloud.r-project.org'))
```
## Demo
```{r}
library(astgrepr)
src <- "library(tidyverse)
x <- rnorm(100, mean = 2)
any(duplicated(y))
plot(x)
any(duplicated(x))
any(is.na(variable))"
root <- src |>
tree_new() |>
tree_root()
# get everything inside rnorm()
root |>
node_find(ast_rule(pattern = "rnorm($$$A)")) |>
node_get_multiple_matches("A") |>
node_text_all()
# find occurrences of any(duplicated())
root |>
node_find_all(ast_rule(pattern = "any(duplicated($A))")) |>
node_text_all()
# find some nodes and replace them with something else
nodes_to_replace <- root |>
node_find_all(
ast_rule(id = "any_na", pattern = "any(is.na($VAR))"),
ast_rule(id = "any_dup", pattern = "any(duplicated($VAR))")
)
fixes <- nodes_to_replace |>
node_replace_all(
any_na = "anyNA(~~VAR~~)",
any_dup = "anyDuplicated(~~VAR~~) > 0"
)
# original code
cat(src)
# new code
tree_rewrite(root, fixes)
```
## Related tools
There is some recent work linking `tree-sitter` and R. Those are not competing
with `astgrepr` but are rather a complement to it:
* [`r-lib/tree-sitter-r`](https://github.com/r-lib/tree-sitter-r): provide the
R grammar to be used with tools built on `tree-sitter`. `astgrepr` relies on
this grammar under the hood.
* [`DavisVaughan/r-tree-sitter`](https://github.com/DavisVaughan/r-tree-sitter):
a companion of `r-lib/tree-sitter-r`. This gives a way to get the tree-sitter
representation of some code directly in R. This is useful to learn how
tree-sitter represents the R grammar, which is required if you want advanced
use of `astgrepr`. However, it doesn't provide a way to easily select specific
nodes (e.g. based on patterns).