Allow overriding the tarball fetcher

.github/workflows/flakehub-publish.yml

@@ -0,0 +1,18 @@
+name: "Publish to FlakeHub"
+on:
+  push:
+    tags:
+      - "v*.*.*"
+jobs:
+  flakehub-publish:
+    runs-on: "ubuntu-latest"
+    permissions:
+      id-token: "write"
+      contents: "read"
+    steps:
+      - uses: "actions/checkout@v3"
+      - uses: "DeterminateSystems/nix-installer-action@main"
+      - uses: "DeterminateSystems/flakehub-push@main"
+        with:
+          name: "edolstra/flake-compat"
+          visibility: "public"

README.md

@@ -5,11 +5,7 @@
 To use, add the following to your `flake.nix`:
 
 ```nix
-inputs.flake-compat = {
-  url = "git+https://git.lix.systems/lix-project/flake-compat";
-  # Optional:
-  flake = false;
-};
+inputs.flake-compat.url = "https://flakehub.com/f/edolstra/flake-compat/1.tar.gz";
 ```
 
 Afterwards, create a `default.nix` file containing the following:
@@ -17,13 +13,10 @@ Afterwards, create a `default.nix` file containing the following:
 ```nix
 (import
   (
-    let
-      lock = builtins.fromJSON (builtins.readFile ./flake.lock);
-      inherit (lock.nodes.flake-compat.locked) narHash rev url;
-    in
-    builtins.fetchTarball {
-      url = "${url}/archive/${rev}.tar.gz";
-      sha256 = narHash;
+    let lock = builtins.fromJSON (builtins.readFile ./flake.lock); in
+    fetchTarball {
+      url = lock.nodes.flake-compat.locked.url or "https://github.com/edolstra/flake-compat/archive/${lock.nodes.flake-compat.locked.rev}.tar.gz";
+      sha256 = lock.nodes.flake-compat.locked.narHash;
     }
   )
   { src = ./.; }

default.nix

@@ -5,7 +5,7 @@
 # containing 'defaultNix' (to be used in 'default.nix'), 'shellNix'
 # (to be used in 'shell.nix').
 
-{ src, system ? builtins.currentSystem or "unknown-system" }:
+{ src, fetchTarball ? builtins.fetchTarball, system ? builtins.currentSystem or "unknown-system" }:
 
 let
 
@@ -73,7 +73,7 @@ let
         shortRev = builtins.substring 0 7 info.rev;
       }
     else
-      # FIXME: add Mercurial inputs.
+      # FIXME: add Mercurial, tarball inputs.
       throw "flake input has unsupported input type '${info.type}'";
 
   callFlake4 = flakeSrc: locks:
@@ -110,8 +110,6 @@ let
           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
@@ -228,8 +226,6 @@ let
 
 in
   rec {
-    inputs = result.inputs // { self = result; };
-
     defaultNix =
       (builtins.removeAttrs result ["__functor"])
       // (if result ? defaultPackage.${system} then { default = result.defaultPackage.${system}; } else {})