@@ -20,7 +20,7 @@ zopfliEncodings = file:
2020 nixpkgs.stdenv.mkDerivation {
2121 name = "encodings";
2222
23− input = file;
23+ input = mkPath file;
2424
2525 builder = builtins.toFile "builder.sh" ''
2626 source "$stdenv/setup"
@@ -46,7 +46,7 @@ gzipEncodings = file:
4646 nixpkgs.stdenv.mkDerivation {
4747 name = "encodings";
4848
49− input = file;
49+ input = mkPath file;
5050
5151 builder = builtins.toFile "builder.sh" ''
5252 source "$stdenv/setup"
@@ -70,7 +70,7 @@ noEncodings = file:
7070 nixpkgs.stdenv.mkDerivation {
7171 name = "encodings";
7272
73− input = file;
73+ input = mkPath file;
7474
7575 builder = builtins.toFile "builder.sh" ''
7676 source "$stdenv/setup"
@@ -203,7 +203,7 @@ hashFile = path:
203203 nixpkgs.nix
204204 ];
205205 preferLocalBuild = true;
206− inherit path;
206+ path = mkPath path;
207207 } ''
208208 nix-hash --flat --base32 --type sha256 "$path" | tr -d '\n' >"$out"
209209 '');
@@ -224,7 +224,30 @@ symlink = path: {
224224 inherit path;
225225};
226226
227−# Given a encoding generation function and a file entry resulting from readDirRecursive in the form { name :: String, value: { path :: String } },
227+# Tests if a given character (string of length 1) is valid for a derivation path name.
228+# Passing a string of length other than 1 is undefined.
229+# :: Char -> Bool
230+isValidDrvNameChar = c: "a" <= c && c <= "z" || "A" <= c && c <= "Z" || "0" <= c && c <= "9" || c == "+" || c == "-" || c == "_" || c == "?" || c == "=" || c == ".";
231+
232+# Convert a string into a string that could be used in a derivation name.
233+# replacement lets you choose how to replace invalid characters. It may be any length.
234+# If it contains invalid characters then the result will also be invalid.
235+# :: { str :: String, replacement :: String } -> String
236+mkValidDrvName = { str, replacement ? "?" }:
237+ let
238+ newName = stringAsChars (c: if isValidDrvNameChar c then c else replacement) str;
239+ in if builtins.substring 0 1 newName == "." then "_" + newName else newName;
240+
241+# Like builtins.path but always ensures the name is valid.
242+mkPath = path:
243+ if builtins.typeOf path == "path" # Don't mess with non-paths
244+ then builtins.path {
245+ inherit path;
246+ name = mkValidDrvName { str = builtins.baseNameOf path; };
247+ }
248+ else path;
249+
250+# Given an encoding generation function and a file entry resulting from readDirRecursive in the form { name :: String, value: { path :: String } },
228251# build a DirEntry for dirToPath with the various encodings of the asset for dirToPath to build into a final directory tree.
229252mkAsset = encodings: {name, value}:
230253 let nameWithHash = "${hashFile value.path}-${name}";