Merge remote-tracking branch 'davidtwco/master'

base/utils/git.zsh

@@ -84,7 +84,6 @@ __zplug::utils::git::checkout()
     local    repo="$1"
     local -a do_not_checkout
     local -A tags
-    local    lock_name
 
     tags[at]="$(__zplug::core::core::run_interfaces 'at' "$repo")"
     tags[dir]="$(__zplug::core::core::run_interfaces 'dir' "$repo")"
@@ -116,20 +115,25 @@ __zplug::utils::git::checkout()
         return 0
     fi
 
-    lock_name="${(j:/:)${(s:/:)tags[dir]}[-2, -1]}"
-    if (( $_zplug_checkout_locks[(I)${lock_name}] )); then
+    # Check if the repository is already checked out
+    # with the branch we are looking for.
+    if __zplug::utils::git::have_checked_out "$tags[at]"; then
         return 0
     fi
 
-    # Acquire lock
-    _zplug_checkout_locks+=( $lock_name )
+    # Check if the repo is already locked by another process, and
+    # pretend to return success. This happens most likely to oh-my-zsh
+    # where multiple plugins refer to the same repo, and only one
+    # checkout is needed for that repo. The original variable-based
+    # lock would not work because parallel checkout commands run in
+    # multiple sub processes and they cannot share variables.
+    if __zplug::utils::git::is_git_locked "$tags[dir]"; then
+        return 0
+    fi
 
     git checkout -q "$tags[at]" \
         2> >(__zplug::log::capture::error) >/dev/null
 
-    # Release lock
-    _zplug_checkout_locks=( ${_zplug_checkout_lock:#${lock_name}} )
-
     if (( $status != 0 )); then
         __zplug::io::print::f \
             --die \
@@ -146,6 +150,16 @@ __zplug::utils::git::have_cloned()
         [[ "$(git rev-parse HEAD 2>/dev/null)" != "HEAD" ]]
 }
 
+__zplug::utils::git::have_checked_out()
+{
+    [[ "$(git rev-parse --abbrev-ref HEAD)" == "$1" ]]
+}
+
+__zplug::utils::git::is_git_locked()
+{
+    [[ -e "$1/.git/index.lock" || -e "$1/.git/HEAD.lock" ]]
+}
+
 # TODO:
 # - __zplug::utils::git::fetch
 # - __zplug::utils::git::pull