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lib/termsupport.zsh

@@ -146,23 +146,16 @@ esac
 # the host name to disambiguate local vs. remote paths.
 function omz_termsupport_cwd {
   setopt localoptions unset
-  # Percent-encode the host and path names. Encoding forks a subshell each,
-  # so keep the result and only redo it when $HOST or $PWD changed.
-  local cache_key="$HOST:$PWD:${KONSOLE_PROFILE_NAME:+1}:${KONSOLE_DBUS_SESSION:+1}"
-  if [[ "$_omz_termsupport_cwd_key" != "$cache_key" ]]; then
-    local URL_HOST URL_PATH
-    URL_HOST="$(omz_urlencode -P "$HOST")" || return 1
-    URL_PATH="$(omz_urlencode -P "$PWD")" || return 1
+  # Percent-encode the host and path names.
+  local URL_HOST URL_PATH
+  URL_HOST="$(omz_urlencode -P $HOST)" || return 1
+  URL_PATH="$(omz_urlencode -P $PWD)" || return 1
 
-    # Konsole errors if the HOST is provided
-    [[ -z "$KONSOLE_PROFILE_NAME" && -z "$KONSOLE_DBUS_SESSION"  ]] || URL_HOST=""
-
-    typeset -g _omz_termsupport_cwd_key="$cache_key"
-    typeset -g _omz_termsupport_cwd_url="file://${URL_HOST}${URL_PATH}"
-  fi
+  # Konsole errors if the HOST is provided
+  [[ -z "$KONSOLE_PROFILE_NAME" && -z "$KONSOLE_DBUS_SESSION"  ]] || URL_HOST=""
 
   # common control sequence (OSC 7) to set current host and path
-  printf "\e]7;%s\e\\" "$_omz_termsupport_cwd_url"
+  printf "\e]7;file://%s%s\e\\" "${URL_HOST}" "${URL_PATH}"
 }
 
 # Use a precmd hook instead of a chpwd hook to avoid contaminating output

oh-my-zsh.sh

@@ -110,9 +110,53 @@ if [[ -z "$ZSH_COMPDUMP" ]]; then
   ZSH_COMPDUMP="${ZDOTDIR:-$HOME}/.zcompdump-${SHORT_HOST}-${ZSH_VERSION}"
 fi
 
+# Resolve the commit $ZSH is checked out at into $REPLY by reading the git
+# directory, so that no git process is forked on every startup.
+# Handles .git files (worktrees, submodules), worktree common dirs, detached
+# HEADs and packed refs. Returns 1 if anything is unexpected.
+_omz_git_head() {
+  local gitdir="$ZSH/.git" common head ref
+  local -a lines
+  REPLY=
+
+  # .git may be a file pointing at the real git dir
+  if [[ -f "$gitdir" ]]; then
+    read -r head 2>/dev/null < "$gitdir" || return 1
+    gitdir="${head#gitdir: }"
+    [[ "$gitdir" = /* ]] || gitdir="$ZSH/$gitdir"
+  fi
+
+  # worktrees keep their refs in the common git dir
+  common="$gitdir"
+  if [[ -f "$gitdir/commondir" ]]; then
+    read -r common 2>/dev/null < "$gitdir/commondir" || return 1
+    [[ "$common" = /* ]] || common="$gitdir/$common"
+  fi
+
+  [[ -r "$gitdir/HEAD" ]] || return 1
+  read -r head 2>/dev/null < "$gitdir/HEAD" || return 1
+
+  # detached HEAD: the file holds the commit itself
+  [[ "$head" = ref:\ * ]] || { REPLY="$head"; return 0 }
+
+  ref="${head#ref: }"
+  if [[ -r "$common/$ref" ]]; then
+    read -r REPLY 2>/dev/null < "$common/$ref" || return 1
+    [[ "$REPLY" != ref:\ * ]] || return 1
+    return 0
+  fi
+
+  [[ -r "$common/packed-refs" ]] || return 1
+  lines=("${(@f)$(<"$common/packed-refs")}")
+  REPLY="${lines[(r)* ${(b)ref}]%% *}"
+  [[ -n "$REPLY" ]]
+}
+
 # Construct zcompdump OMZ metadata
-zcompdump_revision="#omz revision: $(builtin cd -q "$ZSH"; git rev-parse HEAD 2>/dev/null)"
+_omz_git_head || REPLY="$(builtin cd -q "$ZSH"; git rev-parse HEAD 2>/dev/null)"
+zcompdump_revision="#omz revision: $REPLY"
 zcompdump_fpath="#omz fpath: $fpath"
+unset -f _omz_git_head
 
 # Delete the zcompdump file if OMZ zcompdump metadata changed
 if ! command grep -q -Fx "$zcompdump_revision" "$ZSH_COMPDUMP" 2>/dev/null \