Improve loadenv prototype

scripts/profile/loadenv.sh

@@ -10,26 +10,51 @@ mkdir --parents "$ENVDIR"
 function .env {
     declare name="${1}"
 
-    bash --init-file <(cat \
-        ~/.bashrc \
-        <(direnv stdlib) \
-        "$ENVDIR/$name" \
-        <(cat <<< "export PS1='($name) $PS1'") \
+    envdir="$(dirname "$(realpath "$ENVDIR/$name")")"
+
+    # Start a subshell as the simplest way to unload variables at the end.
+    # `init-file` runs commands before going interactive.
+    #
+    # 1. Load bashrc because `init-file` overrides the normal load sequence.
+    # 2. Add env name to shell prompt as Python's virtualenv does.
+    # 3. Move into the envdir so that commands like `pwd` work in the .envrc
+    # 4. Load direnv stdlib because .envrc files may use it.
+    # 5. Load the .envrc without using direnv to use it in any directory.
+    # 6. Move back so that when Bash goes interactive I'm in the same place.
+    #
+    # 
+    bash --init-file <(
+        cat \
+            ~/.bashrc \
+            <(cat <<< "export PS1='($name) $PS1'") \
+            <(cat <<< "pushd '$envdir' > /dev/null") \
+            <(direnv stdlib) \
+            "$ENVDIR/$name" \
+            <(cat <<< "popd > /dev/null") \
     )
 }
 
+# Register a new .envrc or update an existing one. Prompts to confirm update.
 function lnenv {
     declare name="${1}"
 
     ln -s -i -T "$(pwd)/.envrc" "$ENVDIR/$name"
 }
 
+# Unregister an .envrc.
 function rmenv {
     declare name="${1}"
 
     rm "$ENVDIR/$name"
 }
 
+# Lists registered .envrc files.
 function lsenv {
     find "$ENVDIR" -mindepth 1 -maxdepth 1 -printf "%f -> %l\n"
 }
+
+# I discovered similar tools after writing this. The magic words to search on
+# Google for were `bash environment switcher`.
+
+# https://github.com/smarie/env-switcher-gui
+# https://github.com/robdmc/switchenv