refactor(tvix/eval): use EvalIO::read_dir for equivalent builtin

Change-Id: I6d782c07166f51587d2f1d06607823268debb5d5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7574
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This commit is contained in:
Vincent Ambo 2022-12-12 20:02:39 +03:00 committed by tazjin
parent 51deadd983
commit 4cb9ada0df
2 changed files with 77 additions and 30 deletions

View file

@ -1,14 +1,17 @@
use builtin_macros::builtins;
use smol_str::SmolStr;
use std::{
collections::BTreeMap,
env, io,
rc::{Rc, Weak},
env,
rc::Weak,
time::{SystemTime, UNIX_EPOCH},
};
use crate::{
compiler::GlobalsMap,
errors::ErrorKind,
io::FileType,
observer::NoOpObserver,
spans::LightSpan,
value::{Builtin, BuiltinArgument, NixAttrs, Thunk},
@ -35,33 +38,22 @@ mod impure_builtins {
#[builtin("readDir")]
fn builtin_read_dir(vm: &mut VM, path: Value) -> Result<Value, ErrorKind> {
let path = coerce_value_to_path(&path, vm)?;
let mk_err = |err: io::Error| ErrorKind::IO {
path: Some(path.clone()),
error: Rc::new(err),
};
let res = path.read_dir().map_err(mk_err)?.into_iter().flat_map(
|entry| -> Result<(String, &str), ErrorKind> {
let entry = entry.map_err(mk_err)?;
let file_type = entry
.metadata()
.map_err(|err| ErrorKind::IO {
path: Some(entry.path()),
error: Rc::new(err),
})?
.file_type();
let val = if file_type.is_dir() {
"directory"
} else if file_type.is_file() {
"regular"
} else if file_type.is_symlink() {
"symlink"
} else {
"unknown"
};
Ok((entry.file_name().to_string_lossy().to_string(), val))
},
);
let res = vm.io().read_dir(path)?.into_iter().map(|(name, ftype)| {
(
name,
Value::String(
SmolStr::new(match ftype {
FileType::Directory => "directory",
FileType::Regular => "regular",
FileType::Symlink => "symlink",
FileType::Unknown => "unknown",
})
.into(),
),
)
});
Ok(Value::attrs(NixAttrs::from_iter(res)))
}

View file

@ -15,10 +15,21 @@
//! In the context of Nix builds, callers also use this interface to determine
//! how store paths are opened and so on.
use smol_str::SmolStr;
use std::path::PathBuf;
use std::rc::Rc;
use crate::errors::ErrorKind;
/// Types of files as represented by `builtins.readDir` in Nix.
#[derive(Debug)]
pub enum FileType {
Directory,
Regular,
Symlink,
Unknown,
}
/// Defines how filesystem interaction occurs inside of tvix-eval.
pub trait EvalIO {
/// Verify whether the file at the specified path exists.
@ -26,6 +37,10 @@ pub trait EvalIO {
/// Read the file at the specified path to a string.
fn read_to_string(&self, path: PathBuf) -> Result<String, ErrorKind>;
/// Read the directory at the specified path and return the names
/// of its entries associated with their [`FileType`].
fn read_dir(&self, path: PathBuf) -> Result<Vec<(SmolStr, FileType)>, ErrorKind>;
}
/// Implementation of [`EvalIO`] that simply uses the equivalent
@ -38,16 +53,50 @@ impl EvalIO for StdIO {
fn path_exists(&self, path: PathBuf) -> Result<bool, ErrorKind> {
path.try_exists().map_err(|e| ErrorKind::IO {
path: Some(path),
error: std::rc::Rc::new(e),
error: Rc::new(e),
})
}
fn read_to_string(&self, path: PathBuf) -> Result<String, ErrorKind> {
std::fs::read_to_string(&path).map_err(|e| ErrorKind::IO {
path: Some(path),
error: std::rc::Rc::new(e),
error: Rc::new(e),
})
}
fn read_dir(&self, path: PathBuf) -> Result<Vec<(SmolStr, FileType)>, ErrorKind> {
let mut result = vec![];
let mk_err = |err| ErrorKind::IO {
path: Some(path.clone()),
error: Rc::new(err),
};
for entry in path.read_dir().map_err(mk_err)? {
let entry = entry.map_err(mk_err)?;
let file_type = entry
.metadata()
.map_err(|err| ErrorKind::IO {
path: Some(entry.path()),
error: Rc::new(err),
})?
.file_type();
let val = if file_type.is_dir() {
FileType::Directory
} else if file_type.is_file() {
FileType::Regular
} else if file_type.is_symlink() {
FileType::Symlink
} else {
FileType::Unknown
};
result.push((SmolStr::new(entry.file_name().to_string_lossy()), val));
}
Ok(result)
}
}
/// Dummy implementation of [`EvalIO`], can be used in contexts where
@ -66,4 +115,10 @@ impl EvalIO for DummyIO {
"I/O methods are not implemented in DummyIO",
))
}
fn read_dir(&self, _: PathBuf) -> Result<Vec<(SmolStr, FileType)>, ErrorKind> {
Err(ErrorKind::NotImplemented(
"I/O methods are not implemented in DummyIO",
))
}
}