1 files changed, 49 insertions, 19 deletions
diff --git a/pkgs/populate/default.nix b/pkgs/populate/default.nix
index c259b15..f0b3411 100644
--- a/pkgs/populate/default.nix
+++ b/pkgs/populate/default.nix
@@ -1,24 +1,54 @@
 # Populate, which delivers sources to a target directory.  Given populate's
-# arguments, it returns the command delivering them.  implementation selects
-# how: "shell" generates a script from the arguments, "rust" runs the
-# program in this directory with the arguments as JSON.  rustProgram is that
-# program, e.g. one built with cargo during development.
-{ coreutils, dash, findutils, git, jq, nix, openssh, pass, passage, rsync
-, writers
-, implementation ? "shell"
+# arguments, it checks them, and returns a script running the program in
+# this directory with them as JSON.  rustProgram is that program, e.g. one
+# built with cargo during development.  dash, jq, and implementation are
+# unused, and stay for overrides that set them.
+{ coreutils, dash ? null, findutils, git, jq ? null, nix, openssh, pass
+, passage, rsync, writers
+, implementation ? null
 , rustPlatform ? null
 , rustProgram ? import ./program.nix { inherit rustPlatform; }
 }:
 
-if implementation == "shell" then
-  import ./shell.nix {
-    inherit coreutils dash findutils git jq nix openssh pass passage rsync
-      writers;
-  }
-else if implementation == "rust" then
-  import ./rust.nix {
-    inherit coreutils findutils git nix openssh pass passage rsync writers;
-    program = rustProgram;
-  }
-else
-  throw "populate: unknown implementation ${builtins.toJSON implementation}"
+with import ../../lib;
+
+let
+  checks = import ./checks.nix;
+in
+
+{ backup ? false, force ? false, prune ? false, source, target }:
+assert checks.checkTargetPath target.path;
+assert all checks.checkSourceName (attrNames source);
+assert checks.checkInputs source;
+assert checks.checkCopyingWithSudo target source;
+let
+  # Store paths in the arguments stay dependencies of the script, so
+  # building it builds them.
+  spec = toJSON {
+    version = 1;
+    inherit backup force prune source;
+    target = {
+      inherit (target) host path;
+      user = target.user or null;
+      port = if target.port or null == null then null else toString target.port;
+      sudo = target.sudo or false;
+      extraOptions = target.extraOptions or [];
+      # Decided during evaluation, like the other functions of krops do.
+      local = isLocalTarget target;
+    };
+  };
+in
+writers.writeDash "populate.${target.host}" /* sh */ ''
+  set -efu
+  echo + "$0" >&2
+  # The tools populate depends on, in front of others of the same name.
+  PATH=${makeBinPath [
+    coreutils findutils git nix openssh pass passage rsync
+  ]}''${PATH:+:$PATH}
+  export PATH
+  # On a file descriptor of its own, so the commands populate runs keep
+  # standard input.  The JSON is a single line, which can't be the delimiter.
+  exec ${rustProgram}/bin/populate /dev/fd/3 3<<'EOF'
+  ${spec}
+  EOF
+''