3 files changed, 69 insertions, 0 deletions
diff --git a/tests/functional/common/vars-and-functions.sh.in b/tests/functional/common/vars-and-functions.sh.in
index 967d6be54..0bde0180f 100644
--- a/tests/functional/common/vars-and-functions.sh.in
+++ b/tests/functional/common/vars-and-functions.sh.in
@@ -45,6 +45,7 @@ if [[ -n "${NIX_DAEMON_PACKAGE:-}" ]]; then
   DAEMON_PATH="${NIX_DAEMON_PACKAGE}/bin:$DAEMON_PATH"
 fi
 coreutils=@coreutils@
+lsof=@lsof@
 
 export dot=@dot@
 export SHELL="@bash@"
diff --git a/tests/functional/flakes/develop.sh b/tests/functional/flakes/develop.sh
new file mode 100644
index 000000000..e1e53d364
--- /dev/null
+++ b/tests/functional/flakes/develop.sh
@@ -0,0 +1,67 @@
+source ../common.sh
+
+clearStore
+rm -rf $TEST_HOME/.cache $TEST_HOME/.config $TEST_HOME/.local
+
+# Create flake under test.
+cp ../shell-hello.nix ../config.nix $TEST_HOME/
+cat <<EOF >$TEST_HOME/flake.nix
+{
+    inputs.nixpkgs.url = "$TEST_HOME/nixpkgs";
+    outputs = {self, nixpkgs}: {
+      packages.$system.hello = (import ./config.nix).mkDerivation {
+        name = "hello";
+        outputs = [ "out" "dev" ];
+        meta.outputsToInstall = [ "out" ];
+        buildCommand = "";
+      };
+    };
+}
+EOF
+
+# Create fake nixpkgs flake.
+mkdir -p $TEST_HOME/nixpkgs
+cp ../config.nix ../shell.nix $TEST_HOME/nixpkgs
+cat <<EOF >$TEST_HOME/nixpkgs/flake.nix
+{
+    outputs = {self}: {
+      legacyPackages.$system.bashInteractive = (import ./shell.nix {}).bashInteractive;
+    };
+}
+EOF
+
+cd $TEST_HOME
+
+# Test whether `nix develop` passes through environment variables.
+[[ "$(
+    ENVVAR=a nix develop --no-write-lock-file .#hello <<EOF
+echo "\$ENVVAR"
+EOF
+)" = "a" ]]
+
+# Test whether `nix develop --ignore-environment` does _not_ pass through environment variables.
+[[ -z "$(
+    ENVVAR=a nix develop --ignore-environment --no-write-lock-file .#hello <<EOF
+echo "\$ENVVAR"
+EOF
+)" ]]
+
+# Determine the bashInteractive executable.
+nix build --no-write-lock-file './nixpkgs#bashInteractive' --out-link ./bash-interactive
+BASH_INTERACTIVE_EXECUTABLE="$PWD/bash-interactive/bin/bash"
+
+# Test whether `nix develop` sets `SHELL` to nixpkgs#bashInteractive shell.
+[[ "$(
+    SHELL=custom nix develop --no-write-lock-file .#hello <<EOF
+echo "\$SHELL"
+EOF
+)" -ef "$BASH_INTERACTIVE_EXECUTABLE" ]]
+
+# Test whether `nix develop` with ignore environment sets `SHELL` to nixpkgs#bashInteractive shell.
+[[ "$(
+    SHELL=custom nix develop --ignore-environment --no-write-lock-file .#hello <<EOF
+echo "\$SHELL"
+EOF
+)" -ef "$BASH_INTERACTIVE_EXECUTABLE" ]]
+
+clearStore
diff --git a/tests/functional/local.mk b/tests/functional/local.mk
index 9d69c925b..24d772cc7 100644
--- a/tests/functional/local.mk
+++ b/tests/functional/local.mk
@@ -2,6 +2,7 @@ nix_tests = \
   test-infra.sh \
   init.sh \
   flakes/flakes.sh \
+  flakes/develop.sh \
   flakes/run.sh \
   flakes/mercurial.sh \
   flakes/circular.sh \