From c698ec1f220f9be4c4184532f0a6c2a9370f3839 Mon Sep 17 00:00:00 2001
From: Tuomas Tynkkynen <tuomas@tuxera.com>
Date: Sun, 1 Jan 2017 18:42:06 +0200
Subject: [PATCH 1/3] nix-shell: Fix 'nix-shell -i'

The 'args' variable here is shadowing one in the outer scope and its
contents end up unused. This causes any '#! nix-shell' lines to
effectively be ignored. The intention here was to clear the args vector,
as far as I can tell (and it seems to work).
---
 src/nix-build/nix-build.cc | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/nix-build/nix-build.cc b/src/nix-build/nix-build.cc
index 08c679357..4d86f394b 100755
--- a/src/nix-build/nix-build.cc
+++ b/src/nix-build/nix-build.cc
@@ -117,7 +117,7 @@ int main(int argc, char ** argv)
                     inShebang = true;
                     for (int i = 2; i < argc - 1; ++i)
                         savedArgs.push_back(argv[i]);
-                    std::vector<string> args;
+                    args.clear();
                     for (auto line : lines) {
                         line = chomp(line);
                         std::smatch match;

From 018f884ffd834ee339e9b4182b4537a3cd80ee28 Mon Sep 17 00:00:00 2001
From: Tuomas Tynkkynen <tuomas@tuxera.com>
Date: Tue, 3 Jan 2017 09:59:09 +0200
Subject: [PATCH 2/3] nix-shell: Don't act interactive in shebangs

I had observed that 'bash --rcfile' would do nothing in a
non-interactive context and cause nothing to be executed if a script
using nix-shell shebangs were run in a non-interactive context.
---
 src/nix-build/nix-build.cc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/nix-build/nix-build.cc b/src/nix-build/nix-build.cc
index 4d86f394b..ef959fa00 100755
--- a/src/nix-build/nix-build.cc
+++ b/src/nix-build/nix-build.cc
@@ -276,6 +276,7 @@ int main(int argc, char ** argv)
                 if (n >= args.size()) {
                     throw UsageError(format("%1% requires an argument") % arg);
                 }
+                interactive = false;
                 auto interpreter = args[n];
                 auto execArgs = "";
 

From b501bea25fac9c43dfd0d197e16836facd2b63a5 Mon Sep 17 00:00:00 2001
From: Tuomas Tynkkynen <tuomas@tuxera.com>
Date: Sun, 1 Jan 2017 18:45:51 +0200
Subject: [PATCH 3/3] tests: Add simple tests for nix-shell

nix-shell -A, -p and -i are lightly tested.
---
 tests/local.mk         |  2 +-
 tests/nix-shell.sh     | 21 +++++++++++++++++++
 tests/shell.nix        | 46 ++++++++++++++++++++++++++++++++++++++++++
 tests/shell.shebang.sh |  4 ++++
 4 files changed, 72 insertions(+), 1 deletion(-)
 create mode 100644 tests/nix-shell.sh
 create mode 100644 tests/shell.nix
 create mode 100755 tests/shell.shebang.sh

diff --git a/tests/local.mk b/tests/local.mk
index 2ca52144b..b3ce39cda 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -11,7 +11,7 @@ nix_tests = \
   multiple-outputs.sh import-derivation.sh fetchurl.sh optimise-store.sh \
   binary-cache.sh nix-profile.sh repair.sh dump-db.sh case-hack.sh \
   check-reqs.sh pass-as-file.sh tarball.sh restricted.sh \
-  placeholders.sh
+  placeholders.sh nix-shell.sh
   # parallel.sh
 
 install-tests += $(foreach x, $(nix_tests), tests/$(x))
diff --git a/tests/nix-shell.sh b/tests/nix-shell.sh
new file mode 100644
index 000000000..12a0ecd03
--- /dev/null
+++ b/tests/nix-shell.sh
@@ -0,0 +1,21 @@
+source common.sh
+
+clearStore
+
+# Test nix-shell -A
+export IMPURE_VAR=foo
+output=$(nix-shell --pure shell.nix -A shellDrv --run \
+    'echo "$IMPURE_VAR - $VAR_FROM_STDENV_SETUP - $VAR_FROM_NIX"')
+
+[ "$output" = " - foo - bar" ]
+
+# Test nix-shell -p
+output=$(NIX_PATH=nixpkgs=shell.nix nix-shell --pure -p foo bar --run 'echo "$(foo) $(bar)"')
+[ "$output" = "foo bar" ]
+
+# Test nix-shell shebang mode
+sed -e "s|@ENV_PROG@|$(type -p env)|" shell.shebang.sh > $TEST_ROOT/shell.shebang.sh
+chmod a+rx $TEST_ROOT/shell.shebang.sh
+
+output=$($TEST_ROOT/shell.shebang.sh)
+[ "$output" = "foo bar" ]
diff --git a/tests/shell.nix b/tests/shell.nix
new file mode 100644
index 000000000..ed4d6fbaa
--- /dev/null
+++ b/tests/shell.nix
@@ -0,0 +1,46 @@
+{ }:
+
+with import ./config.nix;
+
+rec {
+  setupSh = builtins.toFile "setup" ''
+    export VAR_FROM_STDENV_SETUP=foo
+    for pkg in $buildInputs; do
+      export PATH=$PATH:$pkg/bin
+    done
+  '';
+
+  stdenv = mkDerivation {
+    name = "stdenv";
+    buildCommand = ''
+      mkdir -p $out
+      ln -s ${setupSh} $out/setup
+    '';
+  };
+
+  shellDrv = mkDerivation {
+    name = "shellDrv";
+    builder = "/does/not/exist";
+    VAR_FROM_NIX = "bar";
+    inherit stdenv;
+  };
+
+  # Used by nix-shell -p
+  runCommand = name: args: buildCommand: mkDerivation (args // {
+    inherit name buildCommand stdenv;
+  });
+
+  foo = runCommand "foo" {} ''
+    mkdir -p $out/bin
+    echo 'echo foo' > $out/bin/foo
+    chmod a+rx $out/bin/foo
+  '';
+
+  bar = runCommand "bar" {} ''
+    mkdir -p $out/bin
+    echo 'echo bar' > $out/bin/bar
+    chmod a+rx $out/bin/bar
+  '';
+
+  bash = shell;
+}
diff --git a/tests/shell.shebang.sh b/tests/shell.shebang.sh
new file mode 100755
index 000000000..544e28217
--- /dev/null
+++ b/tests/shell.shebang.sh
@@ -0,0 +1,4 @@
+#! @ENV_PROG@ nix-shell
+#! nix-shell -I nixpkgs=shell.nix --option use-binary-caches false
+#! nix-shell --pure -i bash -p foo bar
+echo "$(foo) $(bar)"