wip: cache environment

init.sh

@@ -114,10 +114,42 @@ if [ "${DOROTHY_LOAD-}" = 'yes' ]; then
 		fi
 	fi
 
-	# init dorothy's environment for the login shell
+	# set the active shell as the detected POSIX (.sh) shell
+	# do not export
+	if [ -n "${BASH_VERSION-}" ]; then
+		ACTIVE_POSIX_SHELL='bash'
+	elif [ -n "${ZSH_VERSION-}" ]; then
+		ACTIVE_POSIX_SHELL='zsh'
+	elif [ "$0" = '-dash' ] || [ "$0" = 'dash' ]; then
+		# dash does not define DASH_VERSION
+		ACTIVE_POSIX_SHELL='dash'
+	elif [ -n "${KSH_VERSION-}" ]; then
+		ACTIVE_POSIX_SHELL='ksh'
+	else
+		ACTIVE_POSIX_SHELL='sh'
+	fi
+
+	PATH_ENV_CACHE=~/.cache/dorothy/env_cache
+	DISABLE_CACHE="yes"
+	LOAD_EXISTING_CACHE_SUCCESS='no'
+
+	if [ "$DISABLE_CACHE" = 'no' ] && [ -f "$PATH_ENV_CACHE" ]; then
+		PREV_ENV_KEY_VALUES="$(env)"
+		if eval "$(cat "$PATH_ENV_CACHE")"; then
+			LOAD_EXISTING_CACHE_SUCCESS='yes'
+			echo "Env loaded successfully via cache."
+			case $- in *i*) . "$DOROTHY/sources/interactive.sh" ;; esac
+		fi
+	fi
+
+	# Init dorothy's environment for the login shell
+	# Needs to be loaded in order to compare loaded cache with prev env.
 	. "$DOROTHY/sources/login.sh"
 
-	# if the login shell is also interactive, then init dorothy for the interactive login shell
-	# [-t 0] and [-s] are true despite [env -i bash -lc ...]
-	case $- in *i*) . "$DOROTHY/sources/interactive.sh" ;; esac
-fi
+	if [ "$DISABLE_CACHE" = 'yes' ] || [ "$LOAD_EXISTING_CACHE_SUCCESS" = 'no' ]; then
+		echo "Load interactive LAST"
+		# if the login shell is also interactive, then init dorothy for the interactive login shell
+		# [-t 0] and [-s] are true despite [env -i bash -lc ...]
+		case $- in *i*) . "$DOROTHY/sources/interactive.sh" ;; esac
+	fi
+fi

sources/environment.sh

@@ -1,22 +1,64 @@
 #!/usr/bin/env sh
 
-# set the active shell as the detected POSIX (.sh) shell
-# do not export
-if [ -n "${BASH_VERSION-}" ]; then
-	ACTIVE_POSIX_SHELL='bash'
-elif [ -n "${ZSH_VERSION-}" ]; then
-	ACTIVE_POSIX_SHELL='zsh'
-elif [ "$0" = '-dash' ] || [ "$0" = 'dash' ]; then
-	# dash does not define DASH_VERSION
-	ACTIVE_POSIX_SHELL='dash'
-elif [ -n "${KSH_VERSION-}" ]; then
-	ACTIVE_POSIX_SHELL='ksh'
-else
-	ACTIVE_POSIX_SHELL='sh'
+# # set the active shell as the detected POSIX (.sh) shell
+# # do not export
+# if [ -n "${BASH_VERSION-}" ]; then
+# 	ACTIVE_POSIX_SHELL='bash'
+# elif [ -n "${ZSH_VERSION-}" ]; then
+# 	ACTIVE_POSIX_SHELL='zsh'
+# elif [ "$0" = '-dash' ] || [ "$0" = 'dash' ]; then
+# 	# dash does not define DASH_VERSION
+# 	ACTIVE_POSIX_SHELL='dash'
+# elif [ -n "${KSH_VERSION-}" ]; then
+# 	ACTIVE_POSIX_SHELL='ksh'
+# else
+# 	ACTIVE_POSIX_SHELL='sh'
+# fi
+
+# setup new env
+if [ "$LOAD_EXISTING_CACHE_SUCCESS" = 'no' ]; then
+	echo "load "
+	eval "$(
+		"$DOROTHY/commands/setup-environment-commands" "$ACTIVE_POSIX_SHELL" || {
+			echo "DOROTHY FAILED TO SETUP ENVIRONMENT, RUN THIS TO DEBUG: bash -x '$DOROTHY/commands/setup-environment-commands' '$ACTIVE_POSIX_SHELL'" >/dev/stderr
+			return 1
+		}
+	)"
+fi
+
+if [ "$LOAD_EXISTING_CACHE_SUCCESS" = 'yes' ]; then
+	# process previous env
+	pairs_formatted="$(echo "$PREV_ENV_KEY_VALUES" | tr '\n' ' ')"
+	# echo "$pairs_formatted"
+	eval "$(
+		env "$pairs_formatted" \
+			"$DOROTHY/commands/setup-environment-commands" "$ACTIVE_POSIX_SHELL" || {
+			echo "DOROTHY FAILED TO SETUP ENVIRONMENT, RUN THIS TO DEBUG: bash -x '$DOROTHY/commands/setup-environment-commands' '$ACTIVE_POSIX_SHELL'" >/dev/stderr
+			return 1
+		}
+	)"
 fi
 
-# set the environment variables
-eval "$("$DOROTHY/commands/setup-environment-commands" "$ACTIVE_POSIX_SHELL" || {
-	echo "DOROTHY FAILED TO SETUP ENVIRONMENT, RUN THIS TO DEBUG: bash -x '$DOROTHY/commands/setup-environment-commands' '$ACTIVE_POSIX_SHELL'" >/dev/stderr
-	return 1
-})"
+# # env '' should be completely redundant with no unforseen consequences, so we
+# # can achieve the conditional loading of setup-environment-commands based
+# # on the cache with the following
+# [ "$LOAD_EXISTING_CACHE_SUCCESS" = 'yes' ] &&
+# 	pairs_formatted="$(echo "$PREV_ENV_KEY_VALUES" | tr '\n' ' ')" || pairs_formatted=''
+# # if [ "$LOAD_EXISTING_CACHE_SUCCESS" = 'yes' ]; then
+# 	# process previous env
+# 	# pairs_formatted="$(echo "$PREV_ENV_KEY_VALUES" | tr '\n' ' ')"
+# 	# echo "$pairs_formatted"
+# 	eval "$(
+# 		env "$pairs_formatted" \
+# 			"$DOROTHY/commands/setup-environment-commands" "$ACTIVE_POSIX_SHELL" || {
+# 			echo "DOROTHY FAILED TO SETUP ENVIRONMENT, RUN THIS TO DEBUG: bash -x '$DOROTHY/commands/setup-environment-commands' '$ACTIVE_POSIX_SHELL'" >/dev/stderr
+# 			return 1
+# 		}
+# 	)"
+# # fi
+
+# save cache
+if [ ! -f "$PATH_ENV_CACHE" ]; then
+	touch "$PATH_ENV_CACHE"
+fi
+export -p >"$PATH_ENV_CACHE"