More robust env.sh | Fix conda activate if in subshell

scripts/build-setup.sh

@@ -250,11 +250,25 @@ if run_step "10"; then
     exit_if_last_command_failed
 fi
 
-cat <<EOT >> env.sh
-# line auto-generated by $0
+# Conda Setup
+# Provide a sourceable snippet that can be used in subshells that may not have
+# inhereted conda functions that would be brought in under a login shell that
+# has run conda init (e.g., VSCode, CI)
+read -r -d '\0' CONDA_ACTIVATE_PREAMBLE <<'END_CONDA_ACTIVATE'
+if ! type conda >& /dev/null; then
+    echo "::ERROR:: you must have conda in your environment first"
+    return 1  # don't want to exit here because this file is sourced
+fi
+
+# if we're sourcing this in a sub process that has conda in the PATH but not as a function, init it again
+conda activate --help >& /dev/null || source $(conda info --base)/etc/profile.d/conda.sh
+\0
+END_CONDA_ACTIVATE
+
+replace_content env.sh build-setup "# line auto-generated by $0
+$CONDA_ACTIVATE_PREAMBLE
 conda activate $CYDIR/.conda-env
-source $CYDIR/scripts/fix-open-files.sh
-EOT
+source $CYDIR/scripts/fix-open-files.sh"
 
 echo "Setup complete!"