populate, krops writeDeploy: refer to generated flakes as path:

Generated flakes got locked with a bare nix flake lock in their directory,
and writeDeploy deployed them by their path.  Nix takes both for the
enclosing Git work tree, if the target directory lies in one, e.g. a home
directory kept in Git, and fails, because generated flakes aren't tracked
there.  Both refer to generated flakes as path: now.

An edge case deploys into a Git work tree, and the deploy test covers
deploying generated flakes.

3 files changed, 41 insertions, 11 deletions

diff --git a/pkgs/krops/default.nix b/pkgs/krops/default.nix
index e4f72cd..46ca66f 100644
--- a/pkgs/krops/default.nix
+++ b/pkgs/krops/default.nix
@@ -15,7 +15,11 @@ in
           (lib.shell.requireFlakes "deploying a flake")}
         NIX_PATH=${lib.escapeShellArg target.path} \
         nixos-rebuild ${lib.escapeShellArgs (args ++ lib.optionals (flake != null) [
-          "--flake" "${target.path}/${flake}"
+          "--flake"
+          # Generated flakes as path:, not just their paths, which Nix takes
+          # for the enclosing Git work tree, if any.
+          (lib.optionalString (lib.hasPrefix ".populate/flakes/" flake) "path:" +
+            "${target.path}/${flake}")
         ])} ${lib.optionalString (flake == null)
           # nixos-rebuild deploys /etc/nixos/flake.nix if it exists.  Any
           # nixos-rebuild doing so supports --no-flake.
diff --git a/pkgs/populate/default.nix b/pkgs/populate/default.nix
index 08a624b..0992b0c 100644
--- a/pkgs/populate/default.nix
+++ b/pkgs/populate/default.nix
@@ -120,7 +120,8 @@ let
           printf '  outputs = inputs: inputs.%s;\n' ${quote (toJSON name)}
           echo '}'
         } > flake.nix
-        nix flake lock >&2
+        # Not just ., which Nix takes for the enclosing Git work tree, if any.
+        nix flake lock ${quote "path:${flakesDir}/${name}"} >&2
       )
     '';
   in
diff --git a/tests/scenarios.nix b/tests/scenarios.nix
index eeeb665..f1a5958 100644
--- a/tests/scenarios.nix
+++ b/tests/scenarios.nix
@@ -455,7 +455,7 @@ assert !(krops.isLocalTarget (targets.remote "/"));
 
   # writeDeploy's arguments to nixos-rebuild, which a stand-in records.
   deploy = matrix "deploy" {
-    flake = [ false true ];
+    flake = [ "none" "source" "generated" ];
     etcFlake = [ false true ];
     buildTarget = [ false true ];
   } (flags: ctx: let
@@ -468,8 +468,14 @@ assert !(krops.isLocalTarget (targets.remote "/"));
         "--target-host" "${target.user}@${target.host}"
       ]
       ++ optional (flags.buildTarget && target.sudo) "--use-remote-sudo"
-      ++ optionals flags.flake [ "--flake" "${build.path}/x" ]
-      ++ optional (flags.etcFlake && !flags.flake) "--no-flake";
+      ++ {
+        none = [];
+        source = [ "--flake" "${build.path}/x" ];
+        # Generated flakes as path:, which an enclosing Git work tree doesn't
+        # capture.
+        generated = [ "--flake" "path:${build.path}/.populate/flakes/x" ];
+      }.${flags.flake}
+      ++ optional (flags.etcFlake && flags.flake == "none") "--no-flake";
   in
     # The local target can't have another build target.
     if flags.buildTarget && ctx.targetKind == "local" then null else {
@@ -485,17 +491,20 @@ assert !(krops.isLocalTarget (targets.remote "/"));
         ''}
       '';
       phases = twice {
-        sources.x =
-          if flags.flake then {
-            flake = {
+        sources =
+          if flags.flake == "none" then {
+            x.file = "/fixtures/alt";
+          } else alt // {
+            x.flake = {
               flake = "/fixtures/top";
               fetchOnTarget = ctx.targetKind == "sudo";
+              inputs = optionalAttrs (flags.flake == "generated") {
+                dep.follows = "alt";
+              };
             };
-          } else {
-            file = "/fixtures/alt";
           };
         deploy = {
-          flake = if flags.flake then "x" else null;
+          flake = if flags.flake == "none" then null else "x";
         } // optionalAttrs flags.buildTarget {
           inherit buildTarget;
         };
@@ -894,6 +903,22 @@ assert !(krops.isLocalTarget (targets.remote "/"));
         '';
       };
     })
+    # The target directory in a Git work tree.
+    (s "gitdir" {
+      prepare = ''
+        mkdir -p "$T"
+        git -C "$T" init -q
+      '';
+      phases = twice {
+        sources = alt // {
+          x.file = { path = "/fixtures/filesrc"; inputs.dep.follows = "alt"; };
+        };
+        check = ''
+          # Not just the path, which Nix takes for the enclosing work tree.
+          expect_eq msg "$(nix_eval_online path:"$T"/.populate/flakes/x#msg)" top:alt,sub
+        '';
+      };
+    })
   ] ++ lib.optional (targetKind == "local")
     # The target has the path the input is locked to.
     (s "uselocal" {