From 04f50406fd93f4193a58083e391b27e195e4bfd5 Mon Sep 17 00:00:00 2001
From: Jade Lovelace <software@lfcode.ca>
Date: Thu, 27 Jun 2024 13:41:10 -0700
Subject: [PATCH] Fix archive reproducibility
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The git archive export-subst option does not have consistent results
over time, since the abbreviated commit hash can get longer over time.

Instead, let's export the full commit hash.

This was found in an audit of source archive reproducibility in nixpkgs:

```
~ » expected=$(nix-store -r /nix/store/4j9rj4m6akjskp0f7k923qff817k6hv5-source)
actual=$(nix-prefetch-url --print-path --unpack --name source https://github.com/yosyshq/abc/archive/896e5e7dedf9b9b1459fa019f1fa8aa8101fdf43.tar.gz | tail -n1)
nix-shell -p diffoscope --run "diffoscope $expected $actual"
this path will be fetched (3.77 MiB download, 34.50 MiB unpacked):
  /nix/store/4j9rj4m6akjskp0f7k923qff817k6hv5-source
copying path '/nix/store/4j9rj4m6akjskp0f7k923qff817k6hv5-source' from 'https://cache.nixos.org'...
warning: you did not specify '--add-root'; the result might be removed by the garbage collector
--- /nix/store/4j9rj4m6akjskp0f7k923qff817k6hv5-source
+++ /nix/store/v7ms5ghibzi8pk71nzlhvsbn7a0rdpy7-source
│   --- /nix/store/4j9rj4m6akjskp0f7k923qff817k6hv5-source/.gitcommit
├── +++ /nix/store/v7ms5ghibzi8pk71nzlhvsbn7a0rdpy7-source/.gitcommit
│ @@ -1 +1 @@
│ -896e5e7de
│ +896e5e7ded
│ ├── stat {}
│ │ @@ -1,7 +1,7 @@
│ │
│ │ -  Size: 10        	Blocks: 1          IO Block: 512    regular file
│ │ +  Size: 11        	Blocks: 1          IO Block: 512    regular file
│ │  Device: 0,24	Access: (0444/-r--r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
│ │
│ │  Modify: 1970-01-01 00:00:01.000000000 +0000
```
---
 .gitcommit | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.gitcommit b/.gitcommit
index 46b7856fb..6828f88dc 100644
--- a/.gitcommit
+++ b/.gitcommit
@@ -1 +1 @@
-$Format:%h$
+$Format:%H$