fix wrong comment

fixes #66

README.md

@@ -2,13 +2,25 @@
 
 ## Usage
 
+> [!WARNING]
+> During the Lix private beta period during which Forgejo is private, this
+> requires configuring netrc in Lix for the tarball download to work.
+>
+> Your netrc should look something like so:
+> ```
+> machine git.lix.systems login YOUR-USERNAME password SOME-PERSONAL-ACCESS-TOKEN-REPO-READ
+> ```
+>
+> We are terribly sorry for the UX for this being very bad
+> ([issue](https://git.lix.systems/lix-project/lix/issues/254)).
+
 To use, add the following to your `flake.nix`:
 
+<!-- FIXME: this can use the standard non-api archive url when we are
+un-privated -->
+
 ```nix
-inputs.flake-compat = {
-  url = "github:edolstra/flake-compat";
-  flake = false;
-};
+inputs.flake-compat.url = "https://git.lix.systems/api/v1/repos/lix-project/flake-compat/archive/main.tar.gz";
 ```
 
 Afterwards, create a `default.nix` file containing the following:
@@ -18,7 +30,7 @@ Afterwards, create a `default.nix` file containing the following:
   (
     let lock = builtins.fromJSON (builtins.readFile ./flake.lock); in
     fetchTarball {
-      url = "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+      url = lock.nodes.flake-compat.locked.url;
       sha256 = lock.nodes.flake-compat.locked.narHash;
     }
   )

default.nix

@@ -13,42 +13,6 @@ let
 
   lockFile = builtins.fromJSON (builtins.readFile lockFilePath);
 
-  # Using custom fetchurl function here so that we can specify outputHashMode.
-  # The hash we get from the lock file is using recursive ingestion even though
-  # it’s not unpacked. So builtins.fetchurl and import <nix/fetchurl.nix> are
-  # insufficient.
-  # Note that this will be a derivation and not a path as fetchTarball is,
-  # causing the hash of this input to be different on flake and non-flake evaluation.
-  fetchurl = { url, sha256 }:
-    derivation {
-      builder = "builtin:fetchurl";
-
-      name = "source";
-      inherit url;
-
-      outputHash = sha256;
-      outputHashAlgo = "sha256";
-      outputHashMode = "recursive";
-      executable = false;
-      unpack = false;
-
-      system = "builtin";
-
-      # No need to double the amount of network traffic
-      preferLocalBuild = true;
-
-      impureEnvVars = [
-        # We borrow these environment variables from the caller to allow
-        # easy proxy configuration.  This is impure, but a fixed-output
-        # derivation like fetchurl is allowed to do so since its result is
-        # by definition pure.
-        "http_proxy" "https_proxy" "ftp_proxy" "all_proxy" "no_proxy"
-      ];
-
-      # To make "nix-prefetch-url" work.
-      urls = [ url ];
-    };
-
   fetchTree =
     info:
     if info.type == "github" then
@@ -80,10 +44,7 @@ let
       } else {
       })
     else if info.type == "path" then
-      { outPath = builtins.path
-          ({ path = info.path; }
-           // (if info ? narHash then { sha256 = info.narHash; } else {})
-          );
+      { outPath = builtins.path { path = info.path; };
         narHash = info.narHash;
       }
     else if info.type == "tarball" then
@@ -92,7 +53,6 @@ let
             ({ inherit (info) url; }
              // (if info ? narHash then { sha256 = info.narHash; } else {})
             );
-        narHash = info.narHash;
       }
     else if info.type == "gitlab" then
       { inherit (info) rev narHash lastModified;
@@ -103,23 +63,17 @@ let
             );
         shortRev = builtins.substring 0 7 info.rev;
       }
-    else if info.type == "file" then
-      { outPath =
-          if builtins.substring 0 7 info.url == "http://" || builtins.substring 0 8 info.url == "https://" then
-            fetchurl
-              ({ inherit (info) url; }
-               // (if info ? narHash then { sha256 = info.narHash; } else {})
-              )
-          else if builtins.substring 0 7 info.url == "file://" then
-            builtins.path
-              ({ path = builtins.substring 7 (-1) info.url; }
-               // (if info ? narHash then { sha256 = info.narHash; } else {})
-              )
-          else throw "can't support url scheme of flake input with url '${info.url}'";
-        narHash = info.narHash;
+    else if info.type == "sourcehut" then
+      { inherit (info) rev narHash lastModified;
+        outPath =
+          fetchTarball
+            ({ url = "https://${info.host or "git.sr.ht"}/${info.owner}/${info.repo}/archive/${info.rev}.tar.gz"; }
+             // (if info ? narHash then { sha256 = info.narHash; } else {})
+            );
+        shortRev = builtins.substring 0 7 info.rev;
       }
     else
-      # FIXME: add Mercurial input
+      # FIXME: add Mercurial inputs.
       throw "flake input has unsupported input type '${info.type}'";
 
   callFlake4 = flakeSrc: locks:
@@ -150,7 +104,22 @@ let
       then
         let res = builtins.fetchGit src;
         in if res.rev == "0000000000000000000000000000000000000000" then removeAttrs res ["rev" "shortRev"]  else res
-      else { outPath = src; };
+      else {
+        outPath =
+          # Massage `src` into a store path.
+          if builtins.isPath src
+          then
+            if dirOf (toString src) == builtins.storeDir
+              # `builtins.storePath` is not available in pure-eval mode.
+              && builtins ? currentSystem
+            then
+              # If it's already a store path, don't copy it again.
+              builtins.storePath src
+            else
+              "${src}"
+          else
+            src;
+      };
     # NB git worktrees have a file for .git, so we don't check the type of .git
     isGit = builtins.pathExists (src + "/.git");
     isShallow = builtins.pathExists (src + "/.git/shallow");
@@ -195,7 +164,9 @@ let
 
           subdir = if key == lockFile.root then "" else node.locked.dir or "";
 
-          flake = import (sourceInfo + (if subdir != "" then "/" else "") + subdir + "/flake.nix");
+          outPath = sourceInfo + ((if subdir == "" then "" else "/") + subdir);
+
+          flake = import (outPath + "/flake.nix");
 
           inputs = builtins.mapAttrs
             (inputName: inputSpec: allNodes.${resolveInput inputSpec})
@@ -222,7 +193,21 @@ let
 
           outputs = flake.outputs (inputs // { self = result; });
 
-          result = outputs // sourceInfo // { inherit inputs; inherit outputs; inherit sourceInfo; };
+          result =
+            outputs
+            # We add the sourceInfo attribute for its metadata, as they are
+            # relevant metadata for the flake. However, the outPath of the
+            # sourceInfo does not necessarily match the outPath of the flake,
+            # as the flake may be in a subdirectory of a source.
+            # This is shadowed in the next //
+            // sourceInfo
+            // {
+              # This shadows the sourceInfo.outPath
+              inherit outPath;
+
+              inherit inputs; inherit outputs; inherit sourceInfo; _type = "flake";
+            };
+
         in
           if node.flake or true then
             assert builtins.isFunction flake.outputs;
@@ -244,7 +229,7 @@ let
 in
   rec {
     defaultNix =
-      result
+      (builtins.removeAttrs result ["__functor"])
       // (if result ? defaultPackage.${system} then { default = result.defaultPackage.${system}; } else {})
       // (if result ? packages.${system}.default then { default = result.packages.${system}.default; } else {});
 

flake.nix

@@ -0,0 +1,6 @@
+{
+  description = "Allow flakes to be used with Nix < 2.4";
+
+  outputs = { self }: {
+  };
+}