From 466271568be7d3bcf0151dc7e09899775ac31f13 Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Fri, 12 May 2023 19:56:04 +0200
Subject: [PATCH] nix: Parse --file relative to shebang script

---
 doc/manual/src/release-notes/rl-next.md |  2 +-
 src/libcmd/installables.cc              |  5 +++--
 tests/functional/flakes/flakes.sh       | 20 ++++++++++++++++++++
 3 files changed, 24 insertions(+), 3 deletions(-)

diff --git a/doc/manual/src/release-notes/rl-next.md b/doc/manual/src/release-notes/rl-next.md
index 28b6d75f5..7eae5d96e 100644
--- a/doc/manual/src/release-notes/rl-next.md
+++ b/doc/manual/src/release-notes/rl-next.md
@@ -4,7 +4,7 @@
   contents of any `#! nix` lines and the script's location to a single call.
 
   Verbatim strings may be passed in double backtick (```` `` ````) quotes.
-  `--expr` resolves relative paths based on the shebang script location.
+  `--file` and `--expr` resolve relative paths based on the script location.
 
   Some examples:
   ```
diff --git a/src/libcmd/installables.cc b/src/libcmd/installables.cc
index 528643dc5..d897a01c4 100644
--- a/src/libcmd/installables.cc
+++ b/src/libcmd/installables.cc
@@ -442,8 +442,9 @@ Installables SourceExprCommand::parseInstallables(
             auto e = state->parseStdin();
             state->eval(e, *vFile);
         }
-        else if (file)
-            state->evalFile(lookupFileArg(*state, *file), *vFile);
+        else if (file) {
+            state->evalFile(lookupFileArg(*state, *file, CanonPath::fromCwd(getCommandBaseDir())), *vFile);
+        }
         else {
             CanonPath dir(CanonPath::fromCwd(getCommandBaseDir()));
             auto e = state->parseExprFromString(*expr, state->rootPath(dir));
diff --git a/tests/functional/flakes/flakes.sh b/tests/functional/flakes/flakes.sh
index 76f3495dd..ccf1699f9 100644
--- a/tests/functional/flakes/flakes.sh
+++ b/tests/functional/flakes/flakes.sh
@@ -123,6 +123,25 @@ echo "$@"
 EOF
 chmod +x $nonFlakeDir/shebang-inline-expr.sh
 
+cat > $nonFlakeDir/fooScript.nix <<"EOF"
+let flake = (builtins.getFlake (toString ../flake1)).packages;
+    fooScript = flake.${builtins.currentSystem}.fooScript;
+ in fooScript
+EOF
+
+cat > $nonFlakeDir/shebang-file.sh <<EOF
+#! $(type -P env) nix
+EOF
+cat >> $nonFlakeDir/shebang-file.sh <<"EOF"
+#! nix --offline shell
+#! nix --impure --file ./fooScript.nix
+#! nix --no-write-lock-file --command bash
+set -ex
+foo
+echo "$@"
+EOF
+chmod +x $nonFlakeDir/shebang-file.sh
+
 # Construct a custom registry, additionally test the --registry flag
 nix registry add --registry "$registry" flake1 "git+file://$flake1Dir"
 nix registry add --registry "$registry" flake2 "git+file://$percentEncodedFlake2Dir"
@@ -571,4 +590,5 @@ expectStderr 1 nix flake metadata "$flake2Dir" --no-allow-dirty --reference-lock
 [[ $($nonFlakeDir/shebang.sh "bar") = "foo"$'\n'"bar" ]]
 [[ $($nonFlakeDir/shebang-comments.sh ) = "foo" ]]
 [[ $($nonFlakeDir/shebang-inline-expr.sh baz) = "foo"$'\n'"baz" ]]
+[[ $($nonFlakeDir/shebang-file.sh baz) = "foo"$'\n'"baz" ]]
 expect 1 $nonFlakeDir/shebang-reject.sh 2>&1 | grepQuiet -F 'error: unsupported unquoted character in nix shebang: *. Use double backticks to escape?'