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feat(tvix/nix-compat-derive): Add deriver for NixDeserialize

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This adds a nix-compat-derive derive crate that implements a deriver
for NixDeserialize implementations. This is to reduce the amount of
code needed to implement deserialization for all the types used by
the Nix daemon protocol.

Change-Id: I484724b550e8a1d5e9adad9555d9dc1374ae95c2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12022
Autosubmit: Brian Olsen <me@griff.name>
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
This commit is contained in:
Brian Olsen 2024-07-22 16:51:42 +02:00 • committed by clbot
parent 9af6920478
commit ced05a2bb6
48 changed files with 2376 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

44
tvix/Cargo.lock generated
View file

@ -2342,6 +2342,7 @@ dependencies = [
"hex-literal", "hex-literal",
"lazy_static", "lazy_static",
"mimalloc", "mimalloc",
"nix-compat-derive",
"nom", "nom",
"num-traits", "num-traits",
"pin-project-lite", "pin-project-lite",
@ -2358,6 +2359,35 @@ dependencies = [
"zstd", "zstd",
] ]
[[package]]
name = "nix-compat-derive"
version = "0.1.0"
dependencies = [
"hex-literal",
"nix-compat",
"pretty_assertions",
"proc-macro2",
"quote",
"rstest",
"syn 2.0.72",
"tokio",
"tokio-test",
]
[[package]]
name = "nix-compat-derive-tests"
version = "0.1.0"
dependencies = [
"hex-literal",
"nix-compat",
"nix-compat-derive",
"pretty_assertions",
"rstest",
"tokio",
"tokio-test",
"trybuild",
]
[[package]] [[package]]
name = "nohash-hasher" name = "nohash-hasher"
version = "0.2.0" version = "0.2.0"
@ -4708,6 +4738,20 @@ version = "0.2.5"
source = "registry+https://github.com/rust-lang/crates.io-index" source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e421abadd41a4225275504ea4d6566923418b7f05506fbc9c0fe86ba7396114b" checksum = "e421abadd41a4225275504ea4d6566923418b7f05506fbc9c0fe86ba7396114b"
[[package]]
name = "trybuild"
version = "1.0.99"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "207aa50d36c4be8d8c6ea829478be44a372c6a77669937bb39c698e52f1491e8"
dependencies = [
"glob",
"serde",
"serde_derive",
"serde_json",
"termcolor",
"toml 0.8.15",
]
[[package]] [[package]]
name = "tvix-build" name = "tvix-build"
version = "0.1.0" version = "0.1.0"

172
tvix/Cargo.nix
View file

@ -55,6 +55,26 @@ rec {
# File a bug if you depend on any for non-debug work! # File a bug if you depend on any for non-debug work!
debug = internal.debugCrate { inherit packageId; }; debug = internal.debugCrate { inherit packageId; };
}; };
"nix-compat-derive" = rec {
packageId = "nix-compat-derive";
build = internal.buildRustCrateWithFeatures {
packageId = "nix-compat-derive";
};
# Debug support which might change between releases.
# File a bug if you depend on any for non-debug work!
debug = internal.debugCrate { inherit packageId; };
};
"nix-compat-derive-tests" = rec {
packageId = "nix-compat-derive-tests";
build = internal.buildRustCrateWithFeatures {
packageId = "nix-compat-derive-tests";
};
# Debug support which might change between releases.
# File a bug if you depend on any for non-debug work!
debug = internal.debugCrate { inherit packageId; };
};
"tvix-build" = rec { "tvix-build" = rec {
packageId = "tvix-build"; packageId = "tvix-build";
build = internal.buildRustCrateWithFeatures { build = internal.buildRustCrateWithFeatures {
@ -7395,6 +7415,12 @@ rec {
name = "mimalloc"; name = "mimalloc";
packageId = "mimalloc"; packageId = "mimalloc";
} }
{
name = "nix-compat-derive";
packageId = "nix-compat-derive";
optional = true;
usesDefaultFeatures = false;
}
{ {
name = "nom"; name = "nom";
packageId = "nom"; packageId = "nom";
@ -7488,12 +7514,115 @@ rec {
features = { features = {
"async" = [ "tokio" ]; "async" = [ "tokio" ];
"bytes" = [ "dep:bytes" ]; "bytes" = [ "dep:bytes" ];
"default" = [ "async" "wire" ]; "default" = [ "async" "wire" "nix-compat-derive" ];
"nix-compat-derive" = [ "dep:nix-compat-derive" ];
"pin-project-lite" = [ "dep:pin-project-lite" ]; "pin-project-lite" = [ "dep:pin-project-lite" ];
"tokio" = [ "dep:tokio" ]; "tokio" = [ "dep:tokio" ];
"wire" = [ "tokio" "pin-project-lite" "bytes" ]; "wire" = [ "tokio" "pin-project-lite" "bytes" ];
}; };
resolvedDefaultFeatures = [ "async" "bytes" "default" "pin-project-lite" "tokio" "wire" ]; resolvedDefaultFeatures = [ "async" "bytes" "default" "nix-compat-derive" "pin-project-lite" "test" "tokio" "wire" ];
};
"nix-compat-derive" = rec {
crateName = "nix-compat-derive";
version = "0.1.0";
edition = "2021";
src = lib.cleanSourceWith { filter = sourceFilter; src = ./nix-compat-derive; };
procMacro = true;
libName = "nix_compat_derive";
dependencies = [
{
name = "proc-macro2";
packageId = "proc-macro2";
features = [ "proc-macro" ];
}
{
name = "quote";
packageId = "quote";
features = [ "proc-macro" ];
}
{
name = "syn";
packageId = "syn 2.0.72";
features = [ "full" "extra-traits" ];
}
];
devDependencies = [
{
name = "hex-literal";
packageId = "hex-literal";
}
{
name = "nix-compat";
packageId = "nix-compat";
usesDefaultFeatures = false;
features = [ "async" "wire" "test" ];
}
{
name = "pretty_assertions";
packageId = "pretty_assertions";
}
{
name = "rstest";
packageId = "rstest";
}
{
name = "tokio";
packageId = "tokio";
features = [ "io-util" "macros" ];
}
{
name = "tokio-test";
packageId = "tokio-test";
}
];
features = {
"default" = [ "external" ];
};
resolvedDefaultFeatures = [ "default" "external" ];
};
"nix-compat-derive-tests" = rec {
crateName = "nix-compat-derive-tests";
version = "0.1.0";
edition = "2021";
src = lib.cleanSourceWith { filter = sourceFilter; src = ./nix-compat-derive-tests; };
devDependencies = [
{
name = "hex-literal";
packageId = "hex-literal";
}
{
name = "nix-compat";
packageId = "nix-compat";
features = [ "test" "wire" ];
}
{
name = "nix-compat-derive";
packageId = "nix-compat-derive";
}
{
name = "pretty_assertions";
packageId = "pretty_assertions";
}
{
name = "rstest";
packageId = "rstest";
}
{
name = "tokio";
packageId = "tokio";
features = [ "io-util" "macros" ];
}
{
name = "tokio-test";
packageId = "tokio-test";
}
{
name = "trybuild";
packageId = "trybuild";
}
];
features = { };
resolvedDefaultFeatures = [ "compile-tests" ];
}; };
"nohash-hasher" = rec { "nohash-hasher" = rec {
crateName = "nohash-hasher"; crateName = "nohash-hasher";
@ -15498,6 +15627,45 @@ rec {
]; ];
}; };
"trybuild" = rec {
crateName = "trybuild";
version = "1.0.99";
edition = "2021";
sha256 = "1s4i2hpyb66676xkg6b6fxm2qdsawj5lfad8ds68vgn46q6sayi0";
authors = [
"David Tolnay <dtolnay@gmail.com>"
];
dependencies = [
{
name = "glob";
packageId = "glob";
}
{
name = "serde";
packageId = "serde";
}
{
name = "serde_derive";
packageId = "serde_derive";
}
{
name = "serde_json";
packageId = "serde_json";
}
{
name = "termcolor";
packageId = "termcolor";
}
{
name = "toml";
packageId = "toml 0.8.15";
}
];
features = {
"diff" = [ "dissimilar" ];
"dissimilar" = [ "dep:dissimilar" ];
};
};
"tvix-build" = rec { "tvix-build" = rec {
crateName = "tvix-build"; crateName = "tvix-build";
version = "0.1.0"; version = "0.1.0";

2
tvix/Cargo.toml
View file

@ -27,6 +27,8 @@ members = [
"glue", "glue",
"nar-bridge", "nar-bridge",
"nix-compat", "nix-compat",
"nix-compat-derive",
"nix-compat-derive-tests",
"serde", "serde",
"store", "store",
"tracing", "tracing",

27
tvix/nix-compat-derive-tests/Cargo.toml Normal file
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@ -0,0 +1,27 @@
[package]
name = "nix-compat-derive-tests"
version = "0.1.0"
edition = "2021"
[features]
compile-tests = []
[dev-dependencies]
hex-literal = "0.4.1"
pretty_assertions = "1.4.0"
rstest = "0.19.0"
tokio-test = "0.4.3"
trybuild = "1.0.96"
[dev-dependencies.nix-compat]
version = "0.1.0"
path = "../nix-compat"
features = ["test", "wire"]
[dev-dependencies.nix-compat-derive]
version = "0.1.0"
path = "../nix-compat-derive"
[dev-dependencies.tokio]
version = "^1.38"
features = ["io-util", "macros"]

5
tvix/nix-compat-derive-tests/default.nix Normal file
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@ -0,0 +1,5 @@
{ depot, ... }:
depot.tvix.crates.workspaceMembers.nix-compat-derive-tests.build.override {
runTests = true;
}

417
tvix/nix-compat-derive-tests/tests/read_derive.rs Normal file
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@ -0,0 +1,417 @@
use std::str::FromStr;
use nix_compat::nix_daemon::de::mock::{Builder, Error};
use nix_compat::nix_daemon::de::NixRead;
use nix_compat_derive::NixDeserialize;
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct UnitTest;
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct EmptyTupleTest();
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct StructTest {
first: u64,
second: String,
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct TupleTest(u64, String);
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct StructVersionTest {
test: u64,
#[nix(version = "20..")]
hello: String,
}
fn default_test() -> StructVersionTest {
StructVersionTest {
test: 89,
hello: String::from("klomp"),
}
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct TupleVersionTest(u64, #[nix(version = "25..")] String);
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
pub struct TupleVersionDefaultTest(
u64,
#[nix(version = "..25", default = "default_test")] StructVersionTest,
);
#[tokio::test]
async fn read_unit() {
let mut mock = Builder::new().build();
let v: UnitTest = mock.read_value().await.unwrap();
assert_eq!(UnitTest, v);
}
#[tokio::test]
async fn read_empty_tuple() {
let mut mock = Builder::new().build();
let v: EmptyTupleTest = mock.read_value().await.unwrap();
assert_eq!(EmptyTupleTest(), v);
}
#[tokio::test]
async fn read_struct() {
let mut mock = Builder::new().read_number(89).read_slice(b"klomp").build();
let v: StructTest = mock.read_value().await.unwrap();
assert_eq!(
StructTest {
first: 89,
second: String::from("klomp"),
},
v
);
}
#[tokio::test]
async fn read_tuple() {
let mut mock = Builder::new().read_number(89).read_slice(b"klomp").build();
let v: TupleTest = mock.read_value().await.unwrap();
assert_eq!(TupleTest(89, String::from("klomp")), v);
}
#[tokio::test]
async fn read_struct_version() {
let mut mock = Builder::new()
.version((1, 20))
.read_number(89)
.read_slice(b"klomp")
.build();
let v: StructVersionTest = mock.read_value().await.unwrap();
assert_eq!(default_test(), v);
}
#[tokio::test]
async fn read_struct_without_version() {
let mut mock = Builder::new().version((1, 19)).read_number(89).build();
let v: StructVersionTest = mock.read_value().await.unwrap();
assert_eq!(
StructVersionTest {
test: 89,
hello: String::new(),
},
v
);
}
#[tokio::test]
async fn read_tuple_version() {
let mut mock = Builder::new()
.version((1, 26))
.read_number(89)
.read_slice(b"klomp")
.build();
let v: TupleVersionTest = mock.read_value().await.unwrap();
assert_eq!(TupleVersionTest(89, "klomp".into()), v);
}
#[tokio::test]
async fn read_tuple_without_version() {
let mut mock = Builder::new().version((1, 19)).read_number(89).build();
let v: TupleVersionTest = mock.read_value().await.unwrap();
assert_eq!(TupleVersionTest(89, String::new()), v);
}
#[tokio::test]
async fn read_complex_1() {
let mut mock = Builder::new()
.version((1, 19))
.read_number(999)
.read_number(666)
.build();
let v: TupleVersionDefaultTest = mock.read_value().await.unwrap();
assert_eq!(
TupleVersionDefaultTest(
999,
StructVersionTest {
test: 666,
hello: String::new()
}
),
v
);
}
#[tokio::test]
async fn read_complex_2() {
let mut mock = Builder::new()
.version((1, 20))
.read_number(999)
.read_number(666)
.read_slice(b"The quick brown \xF0\x9F\xA6\x8A jumps over 13 lazy \xF0\x9F\x90\xB6.")
.build();
let v: TupleVersionDefaultTest = mock.read_value().await.unwrap();
assert_eq!(
TupleVersionDefaultTest(
999,
StructVersionTest {
test: 666,
hello: String::from("The quick brown 🦊 jumps over 13 lazy 🐶.")
}
),
v
);
}
#[tokio::test]
async fn read_complex_3() {
let mut mock = Builder::new().version((1, 25)).read_number(999).build();
let v: TupleVersionDefaultTest = mock.read_value().await.unwrap();
assert_eq!(
TupleVersionDefaultTest(
999,
StructVersionTest {
test: 89,
hello: String::from("klomp")
}
),
v
);
}
#[tokio::test]
async fn read_complex_4() {
let mut mock = Builder::new().version((1, 26)).read_number(999).build();
let v: TupleVersionDefaultTest = mock.read_value().await.unwrap();
assert_eq!(
TupleVersionDefaultTest(
999,
StructVersionTest {
test: 89,
hello: String::from("klomp")
}
),
v
);
}
#[tokio::test]
async fn read_field_invalid_data() {
let mut mock = Builder::new()
.read_number(666)
.read_slice(b"The quick brown \xED\xA0\x80 jumped.")
.build();
let err = mock.read_value::<StructTest>().await.unwrap_err();
assert_eq!(
Error::InvalidData("invalid utf-8 sequence of 1 bytes from index 16".into()),
err
);
}
#[tokio::test]
async fn read_field_missing_data() {
let mut mock = Builder::new().read_number(666).build();
let err = mock.read_value::<StructTest>().await.unwrap_err();
assert_eq!(Error::MissingData("unexpected end-of-file".into()), err);
}
#[tokio::test]
async fn read_field_no_data() {
let mut mock = Builder::new().build();
let err = mock.read_value::<StructTest>().await.unwrap_err();
assert_eq!(Error::MissingData("unexpected end-of-file".into()), err);
}
#[tokio::test]
async fn read_field_reader_error_first() {
let mut mock = Builder::new()
.read_number_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<StructTest>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[tokio::test]
async fn read_field_reader_error_later() {
let mut mock = Builder::new()
.read_number(999)
.read_bytes_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<StructTest>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
#[nix(from_str)]
struct TestFromStr;
impl FromStr for TestFromStr {
type Err = String;
fn from_str(s: &str) -> Result<Self, Self::Err> {
if s == "test" {
Ok(TestFromStr)
} else {
Err(s.into())
}
}
}
#[tokio::test]
async fn read_from_str() {
let mut mock = Builder::new().read_slice(b"test").build();
let value = mock.read_value::<TestFromStr>().await.unwrap();
assert_eq!(TestFromStr, value);
}
#[tokio::test]
async fn read_from_str_invalid_data() {
let mut mock = Builder::new().read_slice(b"wrong string").build();
let err = mock.read_value::<TestFromStr>().await.unwrap_err();
assert_eq!(Error::InvalidData("wrong string".into()), err);
}
#[tokio::test]
async fn read_from_str_invalid_string() {
let mut mock = Builder::new()
.read_slice(b"The quick brown \xED\xA0\x80 jumped.")
.build();
let err = mock.read_value::<TestFromStr>().await.unwrap_err();
assert_eq!(
Error::InvalidData("invalid utf-8 sequence of 1 bytes from index 16".into()),
err
);
}
#[tokio::test]
async fn read_from_str_reader_error() {
let mut mock = Builder::new()
.read_bytes_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<TestFromStr>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
#[nix(try_from = "u64")]
struct TestTryFromU64;
impl TryFrom<u64> for TestTryFromU64 {
type Error = u64;
fn try_from(value: u64) -> Result<TestTryFromU64, Self::Error> {
if value == 42 {
Ok(TestTryFromU64)
} else {
Err(value)
}
}
}
#[tokio::test]
async fn read_try_from_u64() {
let mut mock = Builder::new().read_number(42).build();
let value = mock.read_value::<TestTryFromU64>().await.unwrap();
assert_eq!(TestTryFromU64, value);
}
#[tokio::test]
async fn read_try_from_u64_invalid_data() {
let mut mock = Builder::new().read_number(666).build();
let err = mock.read_value::<TestTryFromU64>().await.unwrap_err();
assert_eq!(Error::InvalidData("666".into()), err);
}
#[tokio::test]
async fn read_try_from_u64_reader_error() {
let mut mock = Builder::new()
.read_number_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<TestTryFromU64>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
#[nix(from = "u64")]
struct TestFromU64;
impl From<u64> for TestFromU64 {
fn from(_value: u64) -> TestFromU64 {
TestFromU64
}
}
#[tokio::test]
async fn read_from_u64() {
let mut mock = Builder::new().read_number(42).build();
let value = mock.read_value::<TestFromU64>().await.unwrap();
assert_eq!(TestFromU64, value);
}
#[tokio::test]
async fn read_from_u64_reader_error() {
let mut mock = Builder::new()
.read_number_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<TestFromU64>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[derive(Debug, PartialEq, Eq, NixDeserialize)]
enum TestEnum {
#[nix(version = "..=19")]
Pre20(TestTryFromU64),
#[nix(version = "20..")]
Post20(StructVersionTest),
}
#[tokio::test]
async fn read_enum_19() {
let mut mock = Builder::new().version((1, 19)).read_number(42).build();
let value = mock.read_value::<TestEnum>().await.unwrap();
assert_eq!(TestEnum::Pre20(TestTryFromU64), value);
}
#[tokio::test]
async fn read_enum_20() {
let mut mock = Builder::new()
.version((1, 20))
.read_number(42)
.read_slice(b"klomp")
.build();
let value = mock.read_value::<TestEnum>().await.unwrap();
assert_eq!(
TestEnum::Post20(StructVersionTest {
test: 42,
hello: "klomp".into(),
}),
value
);
}
#[tokio::test]
async fn read_enum_reader_error() {
let mut mock = Builder::new()
.version((1, 19))
.read_number_error(Error::InvalidData("Bad reader".into()))
.build();
let err = mock.read_value::<TestEnum>().await.unwrap_err();
assert_eq!(Error::InvalidData("Bad reader".into()), err);
}
#[tokio::test]
async fn read_enum_invalid_data_19() {
let mut mock = Builder::new().version((1, 19)).read_number(666).build();
let err = mock.read_value::<TestEnum>().await.unwrap_err();
assert_eq!(Error::InvalidData("666".into()), err);
}
#[tokio::test]
async fn read_enum_invalid_data_20() {
let mut mock = Builder::new()
.version((1, 20))
.read_number(666)
.read_slice(b"The quick brown \xED\xA0\x80 jumped.")
.build();
let err = mock.read_value::<TestEnum>().await.unwrap_err();
assert_eq!(
Error::InvalidData("invalid utf-8 sequence of 1 bytes from index 16".into()),
err
);
}

6
tvix/nix-compat-derive-tests/tests/ui.rs Normal file
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@ -0,0 +1,6 @@
#[cfg(feature = "compile-tests")]
#[test]
fn ui() {
let t = trybuild::TestCases::new();
t.compile_fail("tests/ui/*.rs");
}

10
tvix/nix-compat-derive-tests/tests/ui/deserialize_bad_type.rs Normal file
View file

@ -0,0 +1,10 @@
use nix_compat_derive::NixDeserialize;
pub struct BadType;
#[derive(NixDeserialize)]
pub struct Test {
version: BadType,
}
fn main() {}

21
tvix/nix-compat-derive-tests/tests/ui/deserialize_bad_type.stderr Normal file
View file

@ -0,0 +1,21 @@
error[E0277]: the trait bound `BadType: NixDeserialize` is not satisfied
--> tests/ui/deserialize_bad_type.rs:7:14
|
7 | version: BadType,
| ^^^^^^^ the trait `NixDeserialize` is not implemented for `BadType`
|
= help: the following other types implement trait `NixDeserialize`:
BTreeMap<K, V>
String
Test
Vec<T>
bool
bytes::bytes::Bytes
i64
u64
usize
note: required by a bound in `try_read_value`
--> $WORKSPACE/nix-compat/src/nix_daemon/de/mod.rs
|
| fn try_read_value<V: NixDeserialize>(
| ^^^^^^^^^^^^^^ required by this bound in `NixRead::try_read_value`

13
tvix/nix-compat-derive-tests/tests/ui/deserialize_enum_non_exaustive.rs Normal file
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@ -0,0 +1,13 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub enum Test {
#[nix(version = "..=10")]
Old,
#[nix(version = "15..=17")]
Legacy,
#[nix(version = "50..")]
NewWay,
}
fn main() {}

8
tvix/nix-compat-derive-tests/tests/ui/deserialize_enum_non_exaustive.stderr Normal file
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@ -0,0 +1,8 @@
error[E0004]: non-exhaustive patterns: `11_u8..=14_u8` and `18_u8..=49_u8` not covered
--> tests/ui/deserialize_enum_non_exaustive.rs:3:10
|
3 | #[derive(NixDeserialize)]
| ^^^^^^^^^^^^^^ patterns `11_u8..=14_u8` and `18_u8..=49_u8` not covered
|
= note: the matched value is of type `u8`
= note: this error originates in the derive macro `NixDeserialize` (in Nightly builds, run with -Z macro-backtrace for more info)

7
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_missing.rs Normal file
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@ -0,0 +1,7 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
#[nix(from = "u64")]
pub struct Test;
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_missing.stderr Normal file
View file

@ -0,0 +1,5 @@
error[E0277]: the trait bound `Test: From<u64>` is not satisfied
--> tests/ui/deserialize_from_missing.rs:4:14
|
4 | #[nix(from = "u64")]
| ^^^^^ the trait `From<u64>` is not implemented for `Test`

20
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_str_error_not_display.rs Normal file
View file

@ -0,0 +1,20 @@
use std::str::FromStr;
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
#[nix(from_str)]
pub struct Test;
impl FromStr for Test {
type Err = ();
fn from_str(s: &str) -> Result<Self, Self::Err> {
if s == "test" {
Ok(Test)
} else {
Err(())
}
}
}
fn main() {}

13
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_str_error_not_display.stderr Normal file
View file

@ -0,0 +1,13 @@
error[E0277]: `()` doesn't implement `std::fmt::Display`
--> tests/ui/deserialize_from_str_error_not_display.rs:6:7
|
6 | #[nix(from_str)]
| ^^^^^^^^ `()` cannot be formatted with the default formatter
|
= help: the trait `std::fmt::Display` is not implemented for `()`
= note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
note: required by a bound in `invalid_data`
--> $WORKSPACE/nix-compat/src/nix_daemon/de/mod.rs
|
| fn invalid_data<T: fmt::Display>(msg: T) -> Self {
| ^^^^^^^^^^^^ required by this bound in `Error::invalid_data`

7
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_str_missing.rs Normal file
View file

@ -0,0 +1,7 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
#[nix(from_str)]
pub struct Test;
fn main() {}

16
tvix/nix-compat-derive-tests/tests/ui/deserialize_from_str_missing.stderr Normal file
View file

@ -0,0 +1,16 @@
error[E0277]: the trait bound `Test: FromStr` is not satisfied
--> tests/ui/deserialize_from_str_missing.rs:4:7
|
4 | #[nix(from_str)]
| ^^^^^^^^ the trait `FromStr` is not implemented for `Test`
|
= help: the following other types implement trait `FromStr`:
IpAddr
Ipv4Addr
Ipv6Addr
NonZero<i128>
NonZero<i16>
NonZero<i32>
NonZero<i64>
NonZero<i8>
and $N others

12
tvix/nix-compat-derive-tests/tests/ui/deserialize_missing_default.rs Normal file
View file

@ -0,0 +1,12 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Value(String);
#[derive(NixDeserialize)]
pub struct Test {
#[nix(version = "20..")]
version: Value,
}
fn main() {}

12
tvix/nix-compat-derive-tests/tests/ui/deserialize_missing_default.stderr Normal file
View file

@ -0,0 +1,12 @@
error[E0277]: the trait bound `Value: Default` is not satisfied
--> tests/ui/deserialize_missing_default.rs:6:10
|
6 | #[derive(NixDeserialize)]
| ^^^^^^^^^^^^^^ the trait `Default` is not implemented for `Value`
|
= note: this error originates in the derive macro `NixDeserialize` (in Nightly builds, run with -Z macro-backtrace for more info)
help: consider annotating `Value` with `#[derive(Default)]`
|
4 + #[derive(Default)]
5 | pub struct Value(String);
|

12
tvix/nix-compat-derive-tests/tests/ui/deserialize_missing_default_path.rs Normal file
View file

@ -0,0 +1,12 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Value(String);
#[derive(NixDeserialize)]
pub struct Test {
#[nix(version = "20..", default = "Value::make_default")]
version: Value,
}
fn main() {}

8
tvix/nix-compat-derive-tests/tests/ui/deserialize_missing_default_path.stderr Normal file
View file

@ -0,0 +1,8 @@
error[E0599]: no function or associated item named `make_default` found for struct `Value` in the current scope
--> tests/ui/deserialize_missing_default_path.rs:8:39
|
4 | pub struct Value(String);
| ---------------- function or associated item `make_default` not found for this struct
...
8 | #[nix(version = "20..", default = "Value::make_default")]
| ^^^^^^^^^^^^^^^^^^^^^ function or associated item not found in `Value`

15
tvix/nix-compat-derive-tests/tests/ui/deserialize_remote_missing_attr.rs Normal file
View file

@ -0,0 +1,15 @@
use nix_compat_derive::nix_deserialize_remote;
pub struct Value(String);
impl From<String> for Value {
fn from(s: String) -> Value {
Value(s)
}
}
nix_deserialize_remote!(
#[nix()]
Value
);
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/deserialize_remote_missing_attr.stderr Normal file
View file

@ -0,0 +1,5 @@
error: Missing from_str, from or try_from attribute
--> tests/ui/deserialize_remote_missing_attr.rs:10:25
|
10 | nix_deserialize_remote!(#[nix()] Value);
| ^^^^^^^^^^^^^^

19
tvix/nix-compat-derive-tests/tests/ui/deserialize_try_from_error_not_display.rs Normal file
View file

@ -0,0 +1,19 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
#[nix(try_from = "u64")]
pub struct Test;
impl TryFrom<u64> for Test {
type Error = ();
fn try_from(value: u64) -> Result<Test, Self::Error> {
if value == 42 {
Ok(Test)
} else {
Err(())
}
}
}
fn main() {}

13
tvix/nix-compat-derive-tests/tests/ui/deserialize_try_from_error_not_display.stderr Normal file
View file

@ -0,0 +1,13 @@
error[E0277]: `()` doesn't implement `std::fmt::Display`
--> tests/ui/deserialize_try_from_error_not_display.rs:4:18
|
4 | #[nix(try_from = "u64")]
| ^^^^^ `()` cannot be formatted with the default formatter
|
= help: the trait `std::fmt::Display` is not implemented for `()`
= note: in format strings you may be able to use `{:?}` (or {:#?} for pretty-print) instead
note: required by a bound in `invalid_data`
--> $WORKSPACE/nix-compat/src/nix_daemon/de/mod.rs
|
| fn invalid_data<T: fmt::Display>(msg: T) -> Self {
| ^^^^^^^^^^^^ required by this bound in `Error::invalid_data`

7
tvix/nix-compat-derive-tests/tests/ui/deserialize_try_from_missing.rs Normal file
View file

@ -0,0 +1,7 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
#[nix(try_from = "u64")]
pub struct Test;
fn main() {}

8
tvix/nix-compat-derive-tests/tests/ui/deserialize_try_from_missing.stderr Normal file
View file

@ -0,0 +1,8 @@
error[E0277]: the trait bound `Test: From<u64>` is not satisfied
--> tests/ui/deserialize_try_from_missing.rs:4:18
|
4 | #[nix(try_from = "u64")]
| ^^^^^ the trait `From<u64>` is not implemented for `Test`, which is required by `Test: TryFrom<u64>`
|
= note: required for `u64` to implement `Into<Test>`
= note: required for `Test` to implement `TryFrom<u64>`

9
tvix/nix-compat-derive-tests/tests/ui/parse_bad_default.rs Normal file
View file

@ -0,0 +1,9 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Test {
#[nix(default = 12)]
version: u8,
}
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/parse_bad_default.stderr Normal file
View file

@ -0,0 +1,5 @@
error: expected nix attribute default to be string
--> tests/ui/parse_bad_default.rs:5:21
|
5 | #[nix(default = 12)]
| ^^

9
tvix/nix-compat-derive-tests/tests/ui/parse_bad_default_path.rs Normal file
View file

@ -0,0 +1,9 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Test {
#[nix(default = "12")]
version: u8,
}
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/parse_bad_default_path.stderr Normal file
View file

@ -0,0 +1,5 @@
error: expected identifier
--> tests/ui/parse_bad_default_path.rs:5:21
|
5 | #[nix(default = "12")]
| ^^^^

9
tvix/nix-compat-derive-tests/tests/ui/parse_bad_nix.rs Normal file
View file

@ -0,0 +1,9 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Test {
#[nix]
version: u8,
}
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/parse_bad_nix.stderr Normal file
View file

@ -0,0 +1,5 @@
error: expected attribute arguments in parentheses: #[nix(...)]
--> tests/ui/parse_bad_nix.rs:5:7
|
5 | #[nix]
| ^^^

9
tvix/nix-compat-derive-tests/tests/ui/parse_bad_version.rs Normal file
View file

@ -0,0 +1,9 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Test {
#[nix(version = 12)]
version: u8,
}
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/parse_bad_version.stderr Normal file
View file

@ -0,0 +1,5 @@
error: expected nix attribute version to be string
--> tests/ui/parse_bad_version.rs:5:21
|
5 | #[nix(version = 12)]
| ^^

9
tvix/nix-compat-derive-tests/tests/ui/parse_mising_version.rs Normal file
View file

@ -0,0 +1,9 @@
use nix_compat_derive::NixDeserialize;
#[derive(NixDeserialize)]
pub struct Test {
#[nix(version)]
version: u8,
}
fn main() {}

5
tvix/nix-compat-derive-tests/tests/ui/parse_mising_version.stderr Normal file
View file

@ -0,0 +1,5 @@
error: expected `=`
--> tests/ui/parse_mising_version.rs:5:18
|
5 | #[nix(version)]
| ^

32
tvix/nix-compat-derive/Cargo.toml Normal file
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@ -0,0 +1,32 @@
[package]
name = "nix-compat-derive"
version = "0.1.0"
edition = "2021"
[lib]
proc-macro = true
[features]
external = []
default = ["external"]
[dependencies]
proc-macro2 = { version = "1.0.86", features = ["proc-macro"] }
quote = { version = "1.0.36", features = ["proc-macro"] }
syn = { version = "2.0.72", features = ["full", "extra-traits"] }
[dev-dependencies]
hex-literal = "0.4.1"
pretty_assertions = "1.4.0"
rstest = "0.19.0"
tokio-test = "0.4.3"
[dev-dependencies.tokio]
version = "^1.38"
features = ["io-util", "macros"]
[dev-dependencies.nix-compat]
path = "../nix-compat"
default-features = false
features = ["async", "wire", "test"]

5
tvix/nix-compat-derive/default.nix Normal file
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@ -0,0 +1,5 @@
{ depot, lib, ... }:
depot.tvix.crates.workspaceMembers.nix-compat-derive.build.override {
runTests = true;
}

272
tvix/nix-compat-derive/src/de.rs Normal file
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@ -0,0 +1,272 @@
use proc_macro2::{Span, TokenStream};
use quote::{quote, quote_spanned, ToTokens};
use syn::spanned::Spanned;
use syn::{DeriveInput, Generics, Path, Type};
use crate::internal::attrs::Default;
use crate::internal::inputs::RemoteInput;
use crate::internal::{attrs, Container, Context, Data, Field, Remote, Style, Variant};
pub fn expand_nix_deserialize(nnixrs: Path, input: &mut DeriveInput) -> syn::Result<TokenStream> {
let cx = Context::new();
let cont = Container::from_ast(&cx, nnixrs, input);
cx.check()?;
let cont = cont.unwrap();
let ty = cont.ident_type();
let body = nix_deserialize_body(&cont);
let crate_path = cont.crate_path();
Ok(nix_deserialize_impl(
crate_path,
&ty,
&cont.original.generics,
body,
))
}
pub fn expand_nix_deserialize_remote(
crate_path: Path,
input: &RemoteInput,
) -> syn::Result<TokenStream> {
let cx = Context::new();
let remote = Remote::from_ast(&cx, crate_path, input);
cx.check()?;
let remote = remote.unwrap();
let crate_path = remote.crate_path();
let body = nix_deserialize_body_from(crate_path, &remote.attrs).expect("From tokenstream");
let generics = Generics::default();
Ok(nix_deserialize_impl(crate_path, remote.ty, &generics, body))
}
fn nix_deserialize_impl(
crate_path: &Path,
ty: &Type,
generics: &Generics,
body: TokenStream,
) -> TokenStream {
let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
quote! {
#[automatically_derived]
impl #impl_generics #crate_path::nix_daemon::de::NixDeserialize for #ty #ty_generics
#where_clause
{
#[allow(clippy::manual_async_fn)]
fn try_deserialize<R>(reader: &mut R) -> impl ::std::future::Future<Output=Result<Option<Self>, R::Error>> + Send + '_
where R: ?Sized + #crate_path::nix_daemon::de::NixRead + Send,
{
#body
}
}
}
}
fn nix_deserialize_body_from(
crate_path: &syn::Path,
attrs: &attrs::Container,
) -> Option<TokenStream> {
if let Some(span) = attrs.from_str.as_ref() {
Some(nix_deserialize_from_str(crate_path, span.span()))
} else if let Some(type_from) = attrs.type_from.as_ref() {
Some(nix_deserialize_from(type_from))
} else {
attrs
.type_try_from
.as_ref()
.map(|type_try_from| nix_deserialize_try_from(crate_path, type_try_from))
}
}
fn nix_deserialize_body(cont: &Container) -> TokenStream {
if let Some(tokens) = nix_deserialize_body_from(cont.crate_path(), &cont.attrs) {
tokens
} else {
match &cont.data {
Data::Struct(style, fields) => nix_deserialize_struct(*style, fields),
Data::Enum(variants) => nix_deserialize_enum(variants),
}
}
}
fn nix_deserialize_struct(style: Style, fields: &[Field<'_>]) -> TokenStream {
let read_fields = fields.iter().map(|f| {
let field = f.var_ident();
let ty = f.ty;
let read_value = quote_spanned! {
ty.span()=> if first__ {
first__ = false;
if let Some(v) = reader.try_read_value::<#ty>().await? {
v
} else {
return Ok(None);
}
} else {
reader.read_value::<#ty>().await?
}
};
if let Some(version) = f.attrs.version.as_ref() {
let default = match &f.attrs.default {
Default::Default => quote_spanned!(ty.span()=>::std::default::Default::default),
Default::Path(path) => path.to_token_stream(),
_ => panic!("No default for versioned field"),
};
quote! {
let #field : #ty = if (#version).contains(&reader.version().minor()) {
#read_value
} else {
#default()
};
}
} else {
quote! {
let #field : #ty = #read_value;
}
}
});
let field_names = fields.iter().map(|f| f.var_ident());
let construct = match style {
Style::Struct => {
quote! {
Self { #(#field_names),* }
}
}
Style::Tuple => {
quote! {
Self(#(#field_names),*)
}
}
Style::Unit => quote!(Self),
};
quote! {
#[allow(unused_assignments)]
async move {
let mut first__ = true;
#(#read_fields)*
Ok(Some(#construct))
}
}
}
fn nix_deserialize_variant(variant: &Variant<'_>) -> TokenStream {
let ident = variant.ident;
let read_fields = variant.fields.iter().map(|f| {
let field = f.var_ident();
let ty = f.ty;
let read_value = quote_spanned! {
ty.span()=> if first__ {
first__ = false;
if let Some(v) = reader.try_read_value::<#ty>().await? {
v
} else {
return Ok(None);
}
} else {
reader.read_value::<#ty>().await?
}
};
if let Some(version) = f.attrs.version.as_ref() {
let default = match &f.attrs.default {
Default::Default => quote_spanned!(ty.span()=>::std::default::Default::default),
Default::Path(path) => path.to_token_stream(),
_ => panic!("No default for versioned field"),
};
quote! {
let #field : #ty = if (#version).contains(&reader.version().minor()) {
#read_value
} else {
#default()
};
}
} else {
quote! {
let #field : #ty = #read_value;
}
}
});
let field_names = variant.fields.iter().map(|f| f.var_ident());
let construct = match variant.style {
Style::Struct => {
quote! {
Self::#ident { #(#field_names),* }
}
}
Style::Tuple => {
quote! {
Self::#ident(#(#field_names),*)
}
}
Style::Unit => quote!(Self::#ident),
};
let version = &variant.attrs.version;
quote! {
#version => {
#(#read_fields)*
Ok(Some(#construct))
}
}
}
fn nix_deserialize_enum(variants: &[Variant<'_>]) -> TokenStream {
let match_variant = variants
.iter()
.map(|variant| nix_deserialize_variant(variant));
quote! {
#[allow(unused_assignments)]
async move {
let mut first__ = true;
match reader.version().minor() {
#(#match_variant)*
}
}
}
}
fn nix_deserialize_from(ty: &Type) -> TokenStream {
quote_spanned! {
ty.span() =>
async move {
if let Some(value) = reader.try_read_value::<#ty>().await? {
Ok(Some(<Self as ::std::convert::From<#ty>>::from(value)))
} else {
Ok(None)
}
}
}
}
fn nix_deserialize_try_from(crate_path: &Path, ty: &Type) -> TokenStream {
quote_spanned! {
ty.span() =>
async move {
use #crate_path::nix_daemon::de::Error;
if let Some(item) = reader.try_read_value::<#ty>().await? {
<Self as ::std::convert::TryFrom<#ty>>::try_from(item)
.map_err(Error::invalid_data)
.map(Some)
} else {
Ok(None)
}
}
}
}
fn nix_deserialize_from_str(crate_path: &Path, span: Span) -> TokenStream {
quote_spanned! {
span =>
async move {
use #crate_path::nix_daemon::de::Error;
if let Some(buf) = reader.try_read_bytes().await? {
let s = ::std::str::from_utf8(&buf)
.map_err(Error::invalid_data)?;
<Self as ::std::str::FromStr>::from_str(s)
.map_err(Error::invalid_data)
.map(Some)
} else {
Ok(None)
}
}
}
}

358
tvix/nix-compat-derive/src/internal/attrs.rs Normal file
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@ -0,0 +1,358 @@
use quote::ToTokens;
use syn::meta::ParseNestedMeta;
use syn::parse::Parse;
use syn::{parse_quote, Attribute, Expr, ExprLit, ExprPath, Lit, Token};
use super::symbol::{Symbol, CRATE, DEFAULT, FROM, FROM_STR, NIX, TRY_FROM, VERSION};
use super::Context;
#[derive(Debug, PartialEq, Eq)]
pub enum Default {
None,
#[allow(clippy::enum_variant_names)]
Default,
Path(ExprPath),
}
impl Default {
pub fn is_none(&self) -> bool {
matches!(self, Default::None)
}
}
#[derive(Debug, PartialEq, Eq)]
pub struct Field {
pub default: Default,
pub version: Option<syn::ExprRange>,
}
impl Field {
pub fn from_ast(ctx: &Context, attrs: &Vec<Attribute>) -> Field {
let mut version = None;
let mut default = Default::None;
for attr in attrs {
if attr.path() != NIX {
continue;
}
if let Err(err) = attr.parse_nested_meta(|meta| {
if meta.path == VERSION {
version = parse_lit(ctx, &meta, VERSION)?;
} else if meta.path == DEFAULT {
if meta.input.peek(Token![=]) {
if let Some(path) = parse_lit(ctx, &meta, DEFAULT)? {
default = Default::Path(path);
}
} else {
default = Default::Default;
}
} else {
let path = meta.path.to_token_stream().to_string();
return Err(meta.error(format_args!("unknown nix field attribute '{}'", path)));
}
Ok(())
}) {
eprintln!("{:?}", err.span().source_text());
ctx.syn_error(err);
}
}
if version.is_some() && default.is_none() {
default = Default::Default;
}
Field { default, version }
}
}
#[derive(Debug, PartialEq, Eq)]
pub struct Variant {
pub version: syn::ExprRange,
}
impl Variant {
pub fn from_ast(ctx: &Context, attrs: &Vec<Attribute>) -> Variant {
let mut version = parse_quote!(..);
for attr in attrs {
if attr.path() != NIX {
continue;
}
if let Err(err) = attr.parse_nested_meta(|meta| {
if meta.path == VERSION {
if let Some(v) = parse_lit(ctx, &meta, VERSION)? {
version = v;
}
} else {
let path = meta.path.to_token_stream().to_string();
return Err(
meta.error(format_args!("unknown nix variant attribute '{}'", path))
);
}
Ok(())
}) {
eprintln!("{:?}", err.span().source_text());
ctx.syn_error(err);
}
}
Variant { version }
}
}
#[derive(Debug, PartialEq, Eq)]
pub struct Container {
pub from_str: Option<syn::Path>,
pub type_from: Option<syn::Type>,
pub type_try_from: Option<syn::Type>,
pub crate_path: Option<syn::Path>,
}
impl Container {
pub fn from_ast(ctx: &Context, attrs: &Vec<Attribute>) -> Container {
let mut type_from = None;
let mut type_try_from = None;
let mut crate_path = None;
let mut from_str = None;
for attr in attrs {
if attr.path() != NIX {
continue;
}
if let Err(err) = attr.parse_nested_meta(|meta| {
if meta.path == FROM {
type_from = parse_lit(ctx, &meta, FROM)?;
} else if meta.path == TRY_FROM {
type_try_from = parse_lit(ctx, &meta, TRY_FROM)?;
} else if meta.path == FROM_STR {
from_str = Some(meta.path);
} else if meta.path == CRATE {
crate_path = parse_lit(ctx, &meta, CRATE)?;
} else {
let path = meta.path.to_token_stream().to_string();
return Err(
meta.error(format_args!("unknown nix variant attribute '{}'", path))
);
}
Ok(())
}) {
eprintln!("{:?}", err.span().source_text());
ctx.syn_error(err);
}
}
Container {
from_str,
type_from,
type_try_from,
crate_path,
}
}
}
pub fn get_lit_str(
ctx: &Context,
meta: &ParseNestedMeta,
attr: Symbol,
) -> syn::Result<Option<syn::LitStr>> {
let expr: Expr = meta.value()?.parse()?;
let mut value = &expr;
while let Expr::Group(e) = value {
value = &e.expr;
}
if let Expr::Lit(ExprLit {
lit: Lit::Str(s), ..
}) = value
{
Ok(Some(s.clone()))
} else {
ctx.error_spanned(
expr,
format_args!("expected nix attribute {} to be string", attr),
);
Ok(None)
}
}
pub fn parse_lit<T: Parse>(
ctx: &Context,
meta: &ParseNestedMeta,
attr: Symbol,
) -> syn::Result<Option<T>> {
match get_lit_str(ctx, meta, attr)? {
Some(lit) => Ok(Some(lit.parse()?)),
None => Ok(None),
}
}
#[cfg(test)]
mod test {
use syn::{parse_quote, Attribute};
use crate::internal::Context;
use super::*;
#[test]
fn parse_field_version() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix(version="..34")])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::Default,
version: Some(parse_quote!(..34)),
}
);
}
#[test]
fn parse_field_default() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix(default)])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::Default,
version: None,
}
);
}
#[test]
fn parse_field_default_path() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix(default="Default::default")])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::Path(parse_quote!(Default::default)),
version: None,
}
);
}
#[test]
fn parse_field_both() {
let attrs: Vec<Attribute> =
vec![parse_quote!(#[nix(version="..", default="Default::default")])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::Path(parse_quote!(Default::default)),
version: Some(parse_quote!(..)),
}
);
}
#[test]
fn parse_field_both_rev() {
let attrs: Vec<Attribute> =
vec![parse_quote!(#[nix(default="Default::default", version="..")])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::Path(parse_quote!(Default::default)),
version: Some(parse_quote!(..)),
}
);
}
#[test]
fn parse_field_no_attr() {
let attrs: Vec<Attribute> = vec![];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::None,
version: None,
}
);
}
#[test]
fn parse_field_no_subattrs() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix()])];
let ctx = Context::new();
let field = Field::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
field,
Field {
default: Default::None,
version: None,
}
);
}
#[test]
fn parse_variant_version() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix(version="..34")])];
let ctx = Context::new();
let variant = Variant::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
variant,
Variant {
version: parse_quote!(..34),
}
);
}
#[test]
fn parse_variant_no_attr() {
let attrs: Vec<Attribute> = vec![];
let ctx = Context::new();
let variant = Variant::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
variant,
Variant {
version: parse_quote!(..),
}
);
}
#[test]
fn parse_variant_no_subattrs() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix()])];
let ctx = Context::new();
let variant = Variant::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
variant,
Variant {
version: parse_quote!(..),
}
);
}
#[test]
fn parse_container_try_from() {
let attrs: Vec<Attribute> = vec![parse_quote!(#[nix(try_from="u64")])];
let ctx = Context::new();
let container = Container::from_ast(&ctx, &attrs);
ctx.check().unwrap();
assert_eq!(
container,
Container {
from_str: None,
type_from: None,
type_try_from: Some(parse_quote!(u64)),
crate_path: None,
}
);
}
}

50
tvix/nix-compat-derive/src/internal/ctx.rs Normal file
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@ -0,0 +1,50 @@
use std::cell::RefCell;
use std::fmt;
use std::thread::panicking;
use quote::ToTokens;
pub struct Context {
errors: RefCell<Option<Vec<syn::Error>>>,
}
impl Context {
pub fn new() -> Context {
Context {
errors: RefCell::new(Some(Vec::new())),
}
}
pub fn syn_error(&self, error: syn::Error) {
self.errors
.borrow_mut()
.as_mut()
.take()
.unwrap()
.push(error);
}
pub fn error_spanned<T: ToTokens, D: fmt::Display>(&self, tokens: T, message: D) {
self.syn_error(syn::Error::new_spanned(tokens, message));
}
pub fn check(&self) -> syn::Result<()> {
let mut iter = self.errors.borrow_mut().take().unwrap().into_iter();
let mut err = match iter.next() {
None => return Ok(()),
Some(err) => err,
};
for next_err in iter {
err.combine(next_err);
}
Err(err)
}
}
impl Drop for Context {
fn drop(&mut self) {
if self.errors.borrow().is_some() && !panicking() {
panic!("Context dropped without checking errors");
}
}
}

110
tvix/nix-compat-derive/src/internal/inputs.rs Normal file
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#[derive(Debug, Clone, PartialEq, Eq)]
pub struct RemoteInput {
pub attrs: Vec<syn::Attribute>,
pub ident: syn::Type,
}
impl syn::parse::Parse for RemoteInput {
fn parse(input: syn::parse::ParseStream) -> syn::Result<Self> {
let attrs = input.call(syn::Attribute::parse_outer)?;
let ident = input.parse::<syn::Type>()?;
Ok(RemoteInput { attrs, ident })
}
}
impl quote::ToTokens for RemoteInput {
fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
fn is_outer(attr: &&syn::Attribute) -> bool {
match attr.style {
syn::AttrStyle::Outer => true,
syn::AttrStyle::Inner(_) => false,
}
}
for attr in self.attrs.iter().filter(is_outer) {
attr.to_tokens(tokens);
}
self.ident.to_tokens(tokens);
}
}
#[cfg(test)]
mod test {
use syn::parse_quote;
//use syn::parse::Parse;
use super::*;
#[test]
fn test_input() {
let p: RemoteInput = parse_quote!(u64);
assert_eq!(
p,
RemoteInput {
attrs: vec![],
ident: parse_quote!(u64),
}
);
}
#[test]
fn test_input_attr() {
let p: RemoteInput = parse_quote!(
#[nix]
u64
);
assert_eq!(
p,
RemoteInput {
attrs: vec![parse_quote!(#[nix])],
ident: parse_quote!(u64),
}
);
}
#[test]
fn test_input_attr_multiple() {
let p: RemoteInput = parse_quote!(
#[nix]
#[hello]
u64
);
assert_eq!(
p,
RemoteInput {
attrs: vec![parse_quote!(#[nix]), parse_quote!(#[hello])],
ident: parse_quote!(u64),
}
);
}
#[test]
fn test_input_attr_full() {
let p: RemoteInput = parse_quote!(
#[nix(try_from = "u64")]
usize
);
assert_eq!(
p,
RemoteInput {
attrs: vec![parse_quote!(#[nix(try_from="u64")])],
ident: parse_quote!(usize),
}
);
}
#[test]
fn test_input_attr_other() {
let p: RemoteInput = parse_quote!(
#[muh]
u64
);
assert_eq!(
p,
RemoteInput {
attrs: vec![parse_quote!(#[muh])],
ident: parse_quote!(u64),
}
);
}
}

183
tvix/nix-compat-derive/src/internal/mod.rs Normal file
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use syn::punctuated::Punctuated;
use syn::spanned::Spanned;
use syn::Token;
pub mod attrs;
mod ctx;
pub mod inputs;
mod symbol;
pub use ctx::Context;
pub struct Field<'a> {
pub member: syn::Member,
pub ty: &'a syn::Type,
pub attrs: attrs::Field,
pub original: &'a syn::Field,
}
impl<'a> Field<'a> {
pub fn from_ast(ctx: &Context, idx: usize, field: &'a syn::Field) -> Field<'a> {
let attrs = attrs::Field::from_ast(ctx, &field.attrs);
let member = match &field.ident {
Some(id) => syn::Member::Named(id.clone()),
None => syn::Member::Unnamed(idx.into()),
};
Field {
member,
attrs,
ty: &field.ty,
original: field,
}
}
pub fn var_ident(&self) -> syn::Ident {
match &self.member {
syn::Member::Named(name) => name.clone(),
syn::Member::Unnamed(idx) => {
syn::Ident::new(&format!("field{}", idx.index), self.original.span())
}
}
}
}
pub struct Variant<'a> {
pub ident: &'a syn::Ident,
pub attrs: attrs::Variant,
pub style: Style,
pub fields: Vec<Field<'a>>,
//pub original: &'a syn::Variant,
}
impl<'a> Variant<'a> {
pub fn from_ast(ctx: &Context, variant: &'a syn::Variant) -> Self {
let attrs = attrs::Variant::from_ast(ctx, &variant.attrs);
let (style, fields) = match &variant.fields {
syn::Fields::Named(fields) => (Style::Struct, fields_ast(ctx, &fields.named)),
syn::Fields::Unnamed(fields) => (Style::Tuple, fields_ast(ctx, &fields.unnamed)),
syn::Fields::Unit => (Style::Unit, Vec::new()),
};
Variant {
ident: &variant.ident,
attrs,
style,
fields,
//original: variant,
}
}
}
#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy)]
pub enum Style {
Struct,
Tuple,
Unit,
}
pub enum Data<'a> {
Enum(Vec<Variant<'a>>),
Struct(Style, Vec<Field<'a>>),
}
pub struct Container<'a> {
pub ident: &'a syn::Ident,
pub attrs: attrs::Container,
pub data: Data<'a>,
pub crate_path: syn::Path,
pub original: &'a syn::DeriveInput,
}
impl<'a> Container<'a> {
pub fn from_ast(
ctx: &Context,
crate_path: syn::Path,
input: &'a mut syn::DeriveInput,
) -> Option<Container<'a>> {
let attrs = attrs::Container::from_ast(ctx, &input.attrs);
let data = match &input.data {
syn::Data::Struct(s) => match &s.fields {
syn::Fields::Named(fields) => {
Data::Struct(Style::Struct, fields_ast(ctx, &fields.named))
}
syn::Fields::Unnamed(fields) => {
Data::Struct(Style::Tuple, fields_ast(ctx, &fields.unnamed))
}
syn::Fields::Unit => Data::Struct(Style::Unit, Vec::new()),
},
syn::Data::Enum(e) => {
let variants = e
.variants
.iter()
.map(|variant| Variant::from_ast(ctx, variant))
.collect();
Data::Enum(variants)
}
syn::Data::Union(u) => {
ctx.error_spanned(u.union_token, "Union not supported by nixrs");
return None;
}
};
Some(Container {
ident: &input.ident,
attrs,
data,
crate_path,
original: input,
})
}
pub fn crate_path(&self) -> &syn::Path {
if let Some(crate_path) = self.attrs.crate_path.as_ref() {
crate_path
} else {
&self.crate_path
}
}
pub fn ident_type(&self) -> syn::Type {
let path: syn::Path = self.ident.clone().into();
let tp = syn::TypePath { qself: None, path };
tp.into()
}
}
pub struct Remote<'a> {
pub attrs: attrs::Container,
pub ty: &'a syn::Type,
pub crate_path: syn::Path,
}
impl<'a> Remote<'a> {
pub fn from_ast(
ctx: &Context,
crate_path: syn::Path,
input: &'a inputs::RemoteInput,
) -> Option<Remote<'a>> {
let attrs = attrs::Container::from_ast(ctx, &input.attrs);
if attrs.from_str.is_none() && attrs.type_from.is_none() && attrs.type_try_from.is_none() {
ctx.error_spanned(input, "Missing from_str, from or try_from attribute");
return None;
}
Some(Remote {
ty: &input.ident,
attrs,
crate_path,
})
}
pub fn crate_path(&self) -> &syn::Path {
if let Some(crate_path) = self.attrs.crate_path.as_ref() {
crate_path
} else {
&self.crate_path
}
}
}
fn fields_ast<'a>(ctx: &Context, fields: &'a Punctuated<syn::Field, Token![,]>) -> Vec<Field<'a>> {
fields
.iter()
.enumerate()
.map(|(idx, field)| Field::from_ast(ctx, idx, field))
.collect()
}

32
tvix/nix-compat-derive/src/internal/symbol.rs Normal file
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@ -0,0 +1,32 @@
use std::fmt;
use syn::Path;
#[derive(Copy, Clone)]
pub struct Symbol(&'static str);
pub const NIX: Symbol = Symbol("nix");
pub const VERSION: Symbol = Symbol("version");
pub const DEFAULT: Symbol = Symbol("default");
pub const FROM: Symbol = Symbol("from");
pub const TRY_FROM: Symbol = Symbol("try_from");
pub const FROM_STR: Symbol = Symbol("from_str");
pub const CRATE: Symbol = Symbol("crate");
impl PartialEq<Symbol> for Path {
fn eq(&self, word: &Symbol) -> bool {
self.is_ident(word.0)
}
}
impl<'a> PartialEq<Symbol> for &'a Path {
fn eq(&self, word: &Symbol) -> bool {
self.is_ident(word.0)
}
}
impl fmt::Display for Symbol {
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str(self.0)
}
}

348
tvix/nix-compat-derive/src/lib.rs Normal file
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//! # Using derive
//!
//! 1. [Overview](#overview)
//! 3. [Attributes](#attributes)
//! 1. [Container attributes](#container-attributes)
//! 1. [`#[nix(from_str)]`](#nixfrom_str)
//! 2. [`#[nix(from = "FromType")]`](#nixfrom--fromtype)
//! 3. [`#[nix(try_from = "FromType")]`](#nixtry_from--fromtype)
//! 4. [`#[nix(crate = "...")]`](#nixcrate--)
//! 2. [Variant attributes](#variant-attributes)
//! 1. [`#[nix(version = "range")]`](#nixversion--range)
//! 3. [Field attributes](#field-attributes)
//! 1. [`#[nix(version = "range")]`](#nixversion--range-1)
//! 2. [`#[nix(default)]`](#nixdefault)
//! 3. [`#[nix(default = "path")]`](#nixdefault--path)
//!
//! ## Overview
//!
//! This crate contains derive macros and function-like macros for implementing
//! `NixDeserialize` with less boilerplate.
//!
//! ### Examples
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Unnamed(u64, String);
//! ```
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Fields {
//! number: u64,
//! message: String,
//! };
//! ```
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Ignored;
//! ```
//!
//! ## Attributes
//!
//! To customize the derived trait implementations you can add
//! [attributes](https://doc.rust-lang.org/reference/attributes.html)
//! to containers, fields and variants.
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! #[nix(crate="nix_compat")] // <-- This is a container attribute
//! struct Fields {
//! number: u64,
//! #[nix(version="..20")] // <-- This is a field attribute
//! message: String,
//! };
//!
//! #[derive(NixDeserialize)]
//! #[nix(crate="nix_compat")] // <-- This is also a container attribute
//! enum E {
//! #[nix(version="..10")] // <-- This is a variant attribute
//! A(u64),
//! #[nix(version="10..")] // <-- This is also a variant attribute
//! B(String),
//! }
//! ```
//!
//! ### Container attributes
//!
//! ##### `#[nix(from_str)]`
//!
//! When `from_str` is specified the fields are all ignored and instead a
//! `String` is first deserialized and then `FromStr::from_str` is used
//! to convert this `String` to the container type.
//!
//! This means that the container must implement `FromStr` and the error
//! returned from the `from_str` must implement `Display`.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! #[nix(from_str)]
//! struct MyString(String);
//! impl std::str::FromStr for MyString {
//! type Err = String;
//! fn from_str(s: &str) -> Result<Self, Self::Err> {
//! if s != "bad string" {
//! Ok(MyString(s.to_string()))
//! } else {
//! Err("Got a bad string".to_string())
//! }
//! }
//! }
//! ```
//!
//! ##### `#[nix(from = "FromType")]`
//!
//! When `from` is specified the fields are all ignored and instead a
//! value of `FromType` is first deserialized and then `From::from` is
//! used to convert from this value to the container type.
//!
//! This means that the container must implement `From<FromType>` and
//! `FromType` must implement `NixDeserialize`.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! #[nix(from="usize")]
//! struct MyValue(usize);
//! impl From<usize> for MyValue {
//! fn from(val: usize) -> Self {
//! MyValue(val)
//! }
//! }
//! ```
//!
//! ##### `#[nix(try_from = "FromType")]`
//!
//! With `try_from` a value of `FromType` is first deserialized and then
//! `TryFrom::try_from` is used to convert from this value to the container
//! type.
//!
//! This means that the container must implement `TryFrom<FromType>` and
//! `FromType` must implement `NixDeserialize`.
//! The error returned from `try_from` also needs to implement `Display`.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! #[nix(try_from="usize")]
//! struct WrongAnswer(usize);
//! impl TryFrom<usize> for WrongAnswer {
//! type Error = String;
//! fn try_from(val: usize) -> Result<Self, Self::Error> {
//! if val != 42 {
//! Ok(WrongAnswer(val))
//! } else {
//! Err("Got the answer to life the universe and everything".to_string())
//! }
//! }
//! }
//! ```
//!
//! ##### `#[nix(crate = "...")]`
//!
//! Specify the path to the `nix-compat` crate instance to use when referring
//! to the API in the generated code. This is usually not needed.
//!
//! ### Variant attributes
//!
//! ##### `#[nix(version = "range")]`
//!
//! Specifies the protocol version range where this variant is used.
//! When deriving an enum the `version` attribute is used to select which
//! variant of the enum to deserialize. The range is for minor version and
//! the version ranges of all variants combined must cover all versions
//! without any overlap or the first variant that matches is selected.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #[derive(NixDeserialize)]
//! enum Testing {
//! #[nix(version="..=18")]
//! OldVersion(u64),
//! #[nix(version="19..")]
//! NewVersion(String),
//! }
//! ```
//!
//! ### Field attributes
//!
//! ##### `#[nix(version = "range")]`
//!
//! Specifies the protocol version range where this field is included.
//! The range is for minor version. For example `version = "..20"`
//! includes the field in protocol versions `1.0` to `1.19` and skips
//! it in version `1.20` and above.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Field {
//! number: u64,
//! #[nix(version="..20")]
//! messsage: String,
//! }
//! ```
//!
//! ##### `#[nix(default)]`
//!
//! When a field is skipped because the active protocol version falls
//! outside the range specified in [`#[nix(version = "range")]`](#nixversion--range-1)
//! this attribute indicates that `Default::default()` should be used
//! to get a value for the field. This is also the default
//! when you only specify [`#[nix(version = "range")]`](#nixversion--range-1).
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Field {
//! number: u64,
//! #[nix(version="..20", default)]
//! messsage: String,
//! }
//! ```
//!
//! ##### `#[nix(default = "path")]`
//!
//! When a field is skipped because the active protocol version falls
//! outside the range specified in [`#[nix(version = "range")]`](#nixversion--range-1)
//! this attribute indicates that the function in `path` should be called to
//! get a default value for the field. The given function must be callable
//! as `fn() -> T`.
//! For example `default = "my_value"` would call `my_value()` and `default =
//! "AType::empty"` would call `AType::empty()`.
//!
//! ###### Example
//!
//! ```rust
//! # use nix_compat_derive::NixDeserialize;
//! #
//! #[derive(NixDeserialize)]
//! struct Field {
//! number: u64,
//! #[nix(version="..20", default="missing_string")]
//! messsage: String,
//! }
//!
//! fn missing_string() -> String {
//! "missing string".to_string()
//! }
//! ```
use internal::inputs::RemoteInput;
use proc_macro::TokenStream;
use syn::{parse_quote, DeriveInput};
mod de;
mod internal;
#[cfg(not(feature = "external"))]
#[proc_macro_derive(NixDeserialize, attributes(nix))]
pub fn derive_nix_deserialize(item: TokenStream) -> TokenStream {
let mut input = syn::parse_macro_input!(item as DeriveInput);
let nnixrs: syn::Path = parse_quote!(crate);
de::expand_nix_deserialize(nnixrs, &mut input)
.unwrap_or_else(syn::Error::into_compile_error)
.into()
}
#[cfg(feature = "external")]
#[proc_macro_derive(NixDeserialize, attributes(nix))]
pub fn derive_nix_deserialize(item: TokenStream) -> TokenStream {
let mut input = syn::parse_macro_input!(item as DeriveInput);
let nnixrs: syn::Path = parse_quote!(::nix_compat);
de::expand_nix_deserialize(nnixrs, &mut input)
.unwrap_or_else(syn::Error::into_compile_error)
.into()
}
/// Macro to implement `NixDeserialize` on a type.
/// Sometimes you can't use the deriver to implement `NixDeserialize`
/// (like when dealing with types in Rust standard library) but don't want
/// to implement it yourself. So this macro can be used for those situations
/// where you would derive using `#[nix(from_str)]`,
/// `#[nix(from = "FromType")]` or `#[nix(try_from = "FromType")]` if you
/// could.
///
/// #### Example
///
/// ```rust
/// # use nix_compat_derive::nix_deserialize_remote;
/// #
/// struct MyU64(u64);
///
/// impl From<u64> for MyU64 {
/// fn from(value: u64) -> Self {
/// Self(value)
/// }
/// }
///
/// nix_deserialize_remote!(#[nix(from="u64")] MyU64);
/// ```
#[cfg(not(feature = "external"))]
#[proc_macro]
pub fn nix_deserialize_remote(item: TokenStream) -> TokenStream {
let input = syn::parse_macro_input!(item as RemoteInput);
let crate_path = parse_quote!(crate);
de::expand_nix_deserialize_remote(crate_path, &input)
.unwrap_or_else(syn::Error::into_compile_error)
.into()
}
/// Macro to implement `NixDeserialize` on a type.
/// Sometimes you can't use the deriver to implement `NixDeserialize`
/// (like when dealing with types in Rust standard library) but don't want
/// to implement it yourself. So this macro can be used for those situations
/// where you would derive using `#[nix(from_str)]`,
/// `#[nix(from = "FromType")]` or `#[nix(try_from = "FromType")]` if you
/// could.
///
/// #### Example
///
/// ```rust
/// # use nix_compat_derive::nix_deserialize_remote;
/// #
/// struct MyU64(u64);
///
/// impl From<u64> for MyU64 {
/// fn from(value: u64) -> Self {
/// Self(value)
/// }
/// }
///
/// nix_deserialize_remote!(#[nix(from="u64")] MyU64);
/// ```
#[cfg(feature = "external")]
#[proc_macro]
pub fn nix_deserialize_remote(item: TokenStream) -> TokenStream {
let input = syn::parse_macro_input!(item as RemoteInput);
let crate_path = parse_quote!(::nix_compat);
de::expand_nix_deserialize_remote(crate_path, &input)
.unwrap_or_else(syn::Error::into_compile_error)
.into()
}

8
tvix/nix-compat/Cargo.toml
View file

@ -8,9 +8,10 @@ edition = "2021"
async = ["tokio"] async = ["tokio"]
# code emitting low-level packets used in the daemon protocol. # code emitting low-level packets used in the daemon protocol.
wire = ["tokio", "pin-project-lite", "bytes"] wire = ["tokio", "pin-project-lite", "bytes"]
test = []
# Enable all features by default. # Enable all features by default.
default = ["async", "wire"] default = ["async", "wire", "nix-compat-derive"]
[dependencies] [dependencies]
bitflags = "2.4.1" bitflags = "2.4.1"
@ -33,6 +34,11 @@ tracing = "0.1.37"
optional = true optional = true
version = "1.6.1" version = "1.6.1"
[dependencies.nix-compat-derive]
path = "../nix-compat-derive"
optional = true
default-features = false
[dependencies.tokio] [dependencies.tokio]
optional = true optional = true
version = "1.32.0" version = "1.32.0"

7
tvix/nix-compat/src/nix_daemon/protocol_version.rs
View file

@ -54,6 +54,13 @@ impl From<u16> for ProtocolVersion {
} }
} }
#[cfg(any(test, feature = "test"))]
impl From<(u8, u8)> for ProtocolVersion {
fn from((major, minor): (u8, u8)) -> Self {
Self::from_parts(major, minor)
}
}
impl TryFrom<u64> for ProtocolVersion { impl TryFrom<u64> for ProtocolVersion {
type Error = &'static str; type Error = &'static str;