refactor(tvix/nix-compat): absorb //tvix/derivation

Put this in its src/derivation.

Change-Id: Ic047ab1c2da555a833ee454e10ef60c77537b617
Reviewed-on: https://cl.tvl.fyi/c/depot/+/7967
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Autosubmit: flokli <flokli@flokli.de>

tvix/derivation/src/errors.rs

@@ -1,56 +0,0 @@
-use nix_compat::{nixbase32::Nixbase32DecodeError, store_path::ParseStorePathError};
-use thiserror::Error;
-
-/// Errors that can occur during the validation of Derivation structs.
-#[derive(Debug, Error, PartialEq)]
-pub enum DerivationError {
-    // outputs
-    #[error("no outputs defined")]
-    NoOutputs(),
-    #[error("invalid output name: {0}")]
-    InvalidOutputName(String),
-    #[error("encountered fixed-output derivation, but more than 1 output in total")]
-    MoreThanOneOutputButFixed(),
-    #[error("invalid output name for fixed-output derivation: {0}")]
-    InvalidOutputNameForFixed(String),
-    #[error("unable to validate output {0}: {1}")]
-    InvalidOutput(String, OutputError),
-    // input derivation
-    #[error("unable to parse input derivation path {0}: {1}")]
-    InvalidInputDerivationPath(String, ParseStorePathError),
-    #[error("input derivation {0} doesn't end with .drv")]
-    InvalidInputDerivationPrefix(String),
-    #[error("input derivation {0} output names are empty")]
-    EmptyInputDerivationOutputNames(String),
-    #[error("input derivation {0} output name {1} is invalid")]
-    InvalidInputDerivationOutputName(String, String),
-
-    // input sources
-    #[error("unable to parse input sources path {0}: {1}")]
-    InvalidInputSourcesPath(String, ParseStorePathError),
-
-    // platform
-    #[error("invalid platform field: {0}")]
-    InvalidPlatform(String),
-
-    // builder
-    #[error("invalid builder field: {0}")]
-    InvalidBuilder(String),
-
-    // environment
-    #[error("invalid environment key {0}")]
-    InvalidEnvironmentKey(String),
-}
-
-/// Errors that can occur during the validation of a specific [Output] of a [Derviation].
-#[derive(Debug, Error, PartialEq)]
-pub enum OutputError {
-    #[error("Invalid ouput path {0}: {1}")]
-    InvalidOutputPath(String, ParseStorePathError),
-    #[error("Invalid hash encoding: {0}")]
-    InvalidHashEncoding(String, Nixbase32DecodeError),
-    #[error("Invalid hash algo: {0}")]
-    InvalidHashAlgo(String),
-    #[error("Invalid Digest size {0} for algo {1}")]
-    InvalidDigestSizeForAlgo(usize, String),
-}