SERVER-57047 Remove requirement to specify workdir when subprocess.exec'ing shell scripts

(cherry picked from commit 6135750dab50a54e40929913fa043d33f2d6f26e)

4 files changed, 38 insertions, 15 deletions

diff --git a/evergreen/functions/venv_setup.sh b/evergreen/functions/venv_setup.sh
index 7eb6c3d14a2..0a901296aee 100644
--- a/evergreen/functions/venv_setup.sh
+++ b/evergreen/functions/venv_setup.sh
@@ -1,10 +1,11 @@
 # exit immediately if virtualenv is not found
 set -o errexit
 
-evergreen_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"
-. "$evergreen_dir/../prelude_python.sh"
+evergreen_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)/.."
+. "$evergreen_dir/prelude_workdir.sh"
+. "$evergreen_dir/prelude_python.sh"
 
-python_loc=$(which ${python:-/opt/mongodbtoolchain/v3/bin/python3})
+python_loc=$(which ${python})
 venv_dir="${workdir}/venv"
 if [ -d "$venv_dir" ]; then
   exit 0
@@ -34,7 +35,7 @@ toolchain_txt="$pip_dir/toolchain-requirements.txt"
 
 # the whole prelude cannot be imported because it requires pyyaml to be
 # installed, which happens just below.
-. "$evergreen_dir/../prelude_venv.sh"
+. "$evergreen_dir/prelude_venv.sh"
 
 activate_venv
 echo "Upgrading pip to 21.0.1"
diff --git a/evergreen/prelude.sh b/evergreen/prelude.sh
index 86f41a53c44..a44b69e7a0a 100755
--- a/evergreen/prelude.sh
+++ b/evergreen/prelude.sh
@@ -2,20 +2,12 @@ if [[ "$0" == *"/evergreen/prelude.sh" ]]; then
   echo "ERROR: do not execute this script. source it instead. ie: . prelude.sh"
   exit 1
 fi
+set -o errexit
 
 # path the directory that contains this script.
 evergreen_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"
 
-# bootstrapping python assumes that the user has not cd'd before the prelude.
-# Ensure that here.
-calculated_workdir=$(cd "$evergreen_dir/../.." && echo $PWD)
-if [ "$PWD" != "$calculated_workdir" ]; then
-  echo "ERROR: Your script changed directory before loading prelude.sh. Don't do that"
-  echo "\$PWD: $PWD"
-  echo "\$calculated_workdir: $calculated_workdir"
-  exit 1
-fi
-
+. "$evergreen_dir/prelude_workdir.sh"
 . "$evergreen_dir/prelude_python.sh"
 . "$evergreen_dir/prelude_venv.sh"
 
@@ -79,3 +71,4 @@ function set_sudo {
     set -o errexit
   fi
 }
+set +o errexit
diff --git a/evergreen/prelude_venv.sh b/evergreen/prelude_venv.sh
index 953f4e63d02..728e097ffe0 100644
--- a/evergreen/prelude_venv.sh
+++ b/evergreen/prelude_venv.sh
@@ -13,7 +13,10 @@ function activate_venv {
     fi
     python=python
   else
-    python=${python:-/opt/mongodbtoolchain/v3/bin/python3}
+    if [ -z "$python" ]; then
+      echo "\$python is unset. This should never happen"
+    fi
+    python=${python}
   fi
 
   if [ "Windows_NT" = "$OS" ]; then
diff --git a/evergreen/prelude_workdir.sh b/evergreen/prelude_workdir.sh
new file mode 100644
index 00000000000..2e39ba1f3b8
--- /dev/null
+++ b/evergreen/prelude_workdir.sh
@@ -0,0 +1,26 @@
+calculated_workdir=$(cd "$evergreen_dir/../.." && echo "$PWD")
+pwd_cygpath="$PWD"
+if [ "Windows_NT" = "$OS" ]; then
+  calculated_workdir=$(cygpath -w "$calculated_workdir")
+  pwd_cygpath=$(cygpath -w "$pwd_cygpath")
+fi
+if [ -z "$workdir" ]; then
+  workdir="$calculated_workdir"
+
+# skip this test on Windows. The directories will never match due to the many
+# different path types present on Windows+Cygwin
+elif [ "$workdir" != "$calculated_workdir" ] && [ "Windows_NT" != "$OS" ]; then
+  # if you move the checkout directory (ex: simple project config project),
+  # then this assertion will fail in the future. You need to update
+  # calculated_workdir, and all the relative directories in this file.
+  echo "\$workdir was specified, but didn't match \$calculated_workdir. Did the directory structure change? Update prelude.sh"
+  echo "\$workdir: $workdir"
+  echo "\$calculated_workdir: $calculated_workdir"
+  exit 1
+fi
+if [ "$pwd_cygpath" != "$calculated_workdir" ]; then
+  echo "ERROR: Your script changed directory before loading prelude.sh. Don't do that"
+  echo "\$PWD: $PWD"
+  echo "\$calculated_workdir: $calculated_workdir"
+  exit 1
+fi