[#202] Provide '^out' suffix for deriver on newer nix

Problem: Since 2.15 nix no longer reference '.drv' as derivation
outputs. At the same time, nix before '2.13' doesn't support '.drv'
special suffix handling.

Solution: Provide '^out' suffix for the profile deriver in case
'nix path-info <...>.drv' returns the same '<...>.drv' path.
In other cases either an error about the build result not being present
in the /nix/store is returned or an actual build result path is
returned.

2 files changed, 34 insertions, 21 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 28b124e..ff195da 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,10 +1,12 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+version = 3
+
 [[package]]
 name = "aho-corasick"
-version = "0.7.15"
+version = "0.7.20"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7404febffaa47dac81aa44dba71523c9d069b1bdc50a77db41195149e17f68e5"
+checksum = "cc936419f96fa211c1b9166887b38e5e40b19958e5b895be7c1f93adec7071ac"
 dependencies = [
  "memchr",
 ]
@@ -390,9 +392,9 @@ checksum = "60302e4db3a61da70c0cb7991976248362f30319e88850c487b9b95bbf059e00"
 
 [[package]]
 name = "memchr"
-version = "2.3.4"
+version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0ee1c47aaa256ecabcaea351eae4a9b01ef39ed810004e298d2511ed284b1525"
+checksum = "2dffe52ecf27772e601905b7522cb4ef790d2cc203488bbd0e2fe85fcb74566d"
 
 [[package]]
 name = "merge"
@@ -657,21 +659,20 @@ checksum = "41cc0f7e4d5d4544e8861606a285bb08d3e70712ccc7d2b84d7c0ccfaf4b05ce"
 
 [[package]]
 name = "regex"
-version = "1.4.2"
+version = "1.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "38cf2c13ed4745de91a5eb834e11c00bcc3709e773173b2ce4c56c9fbde04b9c"
+checksum = "8b1f693b24f6ac912f4893ef08244d70b6067480d2f1a46e950c9691e6749d1d"
 dependencies = [
  "aho-corasick",
  "memchr",
  "regex-syntax",
- "thread_local",
 ]
 
 [[package]]
 name = "regex-syntax"
-version = "0.6.21"
+version = "0.6.29"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3b181ba2dcf07aaccad5448e8ead58db5b742cf85dfe035e2227f137a539a189"
+checksum = "f162c6dd7b008981e4d40210aca20b4bd0f9b60ca9271061b07f78537722f2e1"
 
 [[package]]
 name = "rnix"
@@ -869,15 +870,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "thread_local"
-version = "1.0.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
-dependencies = [
- "lazy_static",
-]
-
-[[package]]
 name = "time"
 version = "0.1.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/src/push.rs b/src/push.rs
index 6d9f10d..80fc537 100644
--- a/src/push.rs
+++ b/src/push.rs
@@ -238,19 +238,40 @@ pub async fn build_profile(data: PushProfileData<'_>) -> Result<(), PushProfileE
     )
     .map_err(PushProfileError::ShowDerivationParse)?;
 
-    let derivation_name = derivation_info
+    let &deriver = derivation_info
         .keys()
         .next()
         .ok_or(PushProfileError::ShowDerivationEmpty)?;
 
+    // Since nix 2.15.0 'nix build <path>.drv' will build only the .drv file itself, not the
+    // derivation outputs, '^out' is used to refer to outputs explicitly
+    let new_deriver = &(deriver.to_owned().to_string() + "^out");
+
+    let path_info_output = Command::new("nix")
+        .arg("--experimental-features").arg("nix-command")
+        .arg("path-info")
+        .arg(&deriver)
+        .output().await;
+
+    let deriver = match path_info_output {
+        // In this case we're on 2.15.0 or newer, because 'nix path-infonix path-info <...>.drv'
+        // returns the same '<...>.drv' path.
+        // If 'nix path-info <...>.drv' returns a different path, then we're on pre 2.15.0 nix and
+        // derivation build result is already present in the /nix/store.
+        Ok(path) if std::str::from_utf8(&path.stdout).map(|s| s.trim()) == Ok(deriver) => new_deriver,
+        // At this point, we're sure that derivation path is valid, but
+        // the result of the derivation build is not yet present in the /nix/store.
+        // In this case, 'nix path-info' returns 'error: path '...' is not valid'.
+        _ => deriver,
+    };
     if data.deploy_data.merged_settings.remote_build.unwrap_or(false) {
         if !data.supports_flakes {
             return Err(PushProfileError::RemoteBuildWithLegacyNix)
         }
 
-        build_profile_remotely(&data, derivation_name).await?;
+        build_profile_remotely(&data, &deriver).await?;
     } else {
-        build_profile_locally(&data, derivation_name).await?;
+        build_profile_locally(&data, &deriver).await?;
     }
 
     Ok(())