From 122cc1e3ba448fb0adf397b32f2746aee1d72b2d Mon Sep 17 00:00:00 2001
From: figsoda <figsoda@pm.me>
Date: Mon, 27 Feb 2023 22:26:38 -0500
Subject: [PATCH] convert base32 to sri hash with nix-compat instead of nix cli

---
 Cargo.lock      | 86 +++++++++++++++++++++++++++++++++++++++++++++++++
 Cargo.toml      |  2 ++
 src/prefetch.rs | 26 ++++++---------
 3 files changed, 97 insertions(+), 17 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 9bdb4ac..8c799ab 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -57,6 +57,15 @@ version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
+[[package]]
+name = "block-buffer"
+version = "0.10.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cce20737498f97b993470a6e536b8523f0af7892a4f928cceb1ac5e52ebe7e"
+dependencies = [
+ "generic-array",
+]
+
 [[package]]
 name = "bstr"
 version = "1.3.0"
@@ -172,6 +181,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "cpufeatures"
+version = "0.2.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28d997bd5e24a5928dd43e46dc529867e207907fe0b239c3477d924f7f2ca320"
+dependencies = [
+ "libc",
+]
+
 [[package]]
 name = "crc32fast"
 version = "1.3.2"
@@ -224,12 +242,38 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "crypto-common"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bfb12502f3fc46cca1bb51ac28df9d618d813cdc3d2f25b9fe775a34af26bb3"
+dependencies = [
+ "generic-array",
+ "typenum",
+]
+
+[[package]]
+name = "data-encoding"
+version = "2.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23d8666cb01533c39dde32bcbab8e227b4ed6679b2c925eba05feabea39508fb"
+
 [[package]]
 name = "difflib"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6184e33543162437515c2e2b48714794e37845ec9851711914eec9d308f6ebe8"
 
+[[package]]
+name = "digest"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8168378f4e5023e7218c89c891c0fd8ecdb5e5e4f18cb78f38cf245dd021e76f"
+dependencies = [
+ "block-buffer",
+ "crypto-common",
+]
+
 [[package]]
 name = "doc-comment"
 version = "0.3.3"
@@ -321,6 +365,16 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "generic-array"
+version = "0.14.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bff49e947297f3312447abdca79f45f4738097cc82b06e72054d2223f601f1b9"
+dependencies = [
+ "typenum",
+ "version_check",
+]
+
 [[package]]
 name = "gix-features"
 version = "0.26.5"
@@ -564,6 +618,19 @@ dependencies = [
  "adler",
 ]
 
+[[package]]
+name = "nix-compat"
+version = "0.1.0"
+source = "git+https://code.tvl.fyi/depot.git:/tvix/nix-compat.git#8d4960f273bf627acc4e0f8ff7fb8bec849c67f9"
+dependencies = [
+ "anyhow",
+ "data-encoding",
+ "glob",
+ "serde",
+ "sha2",
+ "thiserror",
+]
+
 [[package]]
 name = "nom8"
 version = "0.2.0"
@@ -605,9 +672,11 @@ dependencies = [
  "clap",
  "clap_complete",
  "clap_mangen",
+ "data-encoding",
  "enum_dispatch",
  "gix-url",
  "itertools",
+ "nix-compat",
  "nu-glob",
  "once_cell",
  "owo-colors",
@@ -894,6 +963,17 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "sha2"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "82e6b795fe2e3b1e845bafcb27aa35405c4d47cdfc92af5fc8d3002f76cebdc0"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "digest",
+]
+
 [[package]]
 name = "shlex"
 version = "1.1.0"
@@ -1079,6 +1159,12 @@ dependencies = [
  "toml_edit",
 ]
 
+[[package]]
+name = "typenum"
+version = "1.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "497961ef93d974e23eb6f433eb5fe1b7930b659f06d12dec6fc44a8f554c0bba"
+
 [[package]]
 name = "unicase"
 version = "2.6.0"
diff --git a/Cargo.toml b/Cargo.toml
index 000a42d..43b474a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,9 +14,11 @@ categories = ["command-line-utilities"]
 [dependencies]
 anyhow = "1.0.69"
 bstr = "1.3.0"
+data-encoding = "2.3.3"
 enum_dispatch = "0.3.11"
 gix-url = "0.13.3"
 itertools = "0.10.5"
+nix-compat = { git = "https://code.tvl.fyi/depot.git:/tvix/nix-compat.git" }
 once_cell = "1.17.1"
 owo-colors = { version = "3.5.0", features = ["supports-colors"] }
 rustc-hash = "1.1.0"
diff --git a/src/prefetch.rs b/src/prefetch.rs
index 4c5ceac..7f21c83 100644
--- a/src/prefetch.rs
+++ b/src/prefetch.rs
@@ -1,4 +1,6 @@
 use anyhow::{anyhow, bail, Result};
+use data_encoding::BASE64;
+use nix_compat::nixbase32;
 use serde::Deserialize;
 
 use std::{
@@ -71,6 +73,8 @@ pub fn git_prefetch(git_scheme: bool, url: &str, rev: &str, submodules: bool) ->
 }
 
 pub fn url_prefetch(url: String, unpack: bool) -> Result<String> {
+    use bstr::ByteSlice;
+
     let mut cmd = Command::new("nix-prefetch-url");
     if unpack {
         cmd.arg("--unpack");
@@ -80,23 +84,11 @@ pub fn url_prefetch(url: String, unpack: bool) -> Result<String> {
     }
     cmd.arg(url);
 
-    let hash = String::from_utf8(cmd.get_stdout()?)?;
-    let hash = hash.trim_end();
-
-    info!("$ nix hash to-sri --experimental-features nix-command --type sha256 {hash}");
-    Ok(String::from_utf8(
-        Command::new("nix")
-            .arg("hash")
-            .arg("to-sri")
-            .arg("--experimental-features")
-            .arg("nix-command")
-            .arg("--type")
-            .arg("sha256")
-            .arg(hash)
-            .get_stdout()?,
-    )?
-    .trim_end()
-    .into())
+    let hash = cmd.get_stdout()?;
+    Ok(format!(
+        "sha256-{}",
+        BASE64.encode(&nixbase32::decode(hash.trim_end())?),
+    ))
 }
 
 pub fn fod_prefetch(expr: String) -> Result<String> {