pi: extensions as a directory of links, so a machine can have its own

~/.pi/agent/extensions was a link to the repo's directory, so anything that
installs a pi extension wrote into this checkout -- herdr's pi integration did,
on one machine. It is now a real directory with the repo's tracked extensions
linked in one by one, and a file a machine adds there stays that machine's.
pi follows the links, and skips a dangling one silently, so an extension
deleted from the repo leaves a harmless stale link.

The old directory link is removed first: linking into it would write through
to the repo and turn its files into links to themselves. Only tracked files are
linked, so a machine's leftovers in the repo's directory are not linked back.

The filed version put this loop in link.sh; it lives in link/pi.sh, since
link.sh holds one-line links only and a part also obeys ~/.config/dot/skip.

From change request 3f6b05.

1 files changed, 32 insertions, 1 deletions

diff --git a/link/pi.sh b/link/pi.sh
index 0fde248..5aec48f 100755
--- a/link/pi.sh
+++ b/link/pi.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 
-# pi's settings.json, generated. Dry run by default; pass `yes` to apply.
+# pi's extensions directory, and its settings.json and models.json, generated.
+# Dry run by default; pass `yes` to apply.
 
 set -euo pipefail
 
@@ -40,6 +41,36 @@ then
   exit 0
 fi
 
+# pi's extensions: a real directory, with this repo's tracked extensions linked
+# in one by one, so an extension only one machine has -- herdr's pi integration
+# writes herdr-agent-state.ts here -- sits beside them instead of landing in this
+# checkout. pi loads every *.ts and *.js there and follows links, and it skips a
+# dangling one silently (resource-loader.js, pi 1.0.0), so the link left behind
+# by an extension deleted from the repo does no harm.
+#
+# Machines used to link the whole directory to the repo. That link goes first:
+# linking into it would write through to the repo and turn its files into links
+# to themselves. Tracked files only, so nothing a machine left in the repo's
+# directory is linked back in.
+pi_extensions="$pi_dir/extensions"
+if [[ -L "$pi_extensions" ]]
+then
+  if [[ -n "${is_dry_run}" ]]
+  then
+    yellow "$pi_extensions is a link to the repo; will become a directory of links to its tracked files"
+  else
+    rm "$pi_extensions"
+  fi
+fi
+if [[ ! -L "$pi_extensions" ]]
+then
+  [[ -n "${is_dry_run}" ]] || mkdir -p "$pi_extensions"
+  while IFS= read -r -d '' f
+  do
+    link "$dotfiles_dir/$f" "$pi_extensions/$(basename "$f")"
+  done < <(git -C "$dotfiles_dir" ls-files -z -- config/pi/extensions)
+fi
+
 pi_status="$(DRY_RUN="$is_dry_run" python3 "$dotfiles_dir/link/pi-settings.py" \
   "$config_dir/pi/settings.json" \
   "$xdg_config_dir/pi/settings.d" \