feat(git): use remote default branch to guess main branch (#13212)

Co-authored-by: Carlo Sala <carlosalag@protonmail.com>

plugins/chruby/chruby.plugin.zsh

@@ -15,6 +15,13 @@ _source-from-omz-settings() {
   fi
 }
 
+_source-from-default-location() {
+  [[ -r /usr/local/share/chruby/chruby.sh ]] || return 1
+
+  source /usr/local/share/chruby/chruby.sh
+  source /usr/local/share/chruby/auto.sh
+}
+
 _source-from-homebrew() {
   (( $+commands[brew] )) || return 1
 
@@ -36,27 +43,14 @@ _source-from-homebrew() {
   source $_brew_prefix/share/chruby/auto.sh
 }
 
-_load-chruby-dirs() {
-  local dir
-  for dir in "$HOME/.rubies" "$PREFIX/opt/rubies"; do
-    if [[ -d "$dir" ]]; then
-      RUBIES+=("$dir")
-    fi
-  done
-}
-
 # Load chruby
-if _source-from-omz-settings; then
+_source-from-omz-settings || \
-  _load-chruby-dirs
+  _source-from-default-location || \
-elif [[ -r "/usr/local/share/chruby/chruby.sh" ]] ; then
+  _source-from-homebrew
-  source /usr/local/share/chruby/chruby.sh
-  source /usr/local/share/chruby/auto.sh
-  _load-chruby-dirs
-elif _source-from-homebrew; then
-  _load-chruby-dirs
-fi
 
-unfunction _source-from-homebrew _source-from-omz-settings _load-chruby-dirs
+unfunction _source-from-homebrew \
+           _source-from-default-location \
+           _source-from-omz-settings
 
 
 ## chruby utility functions and aliases

plugins/git/git.plugin.zsh

@@ -31,10 +31,12 @@ function git_develop_branch() {
   return 1
 }
 
-# Check if main exists and use instead of master
+# Get the default branch name from common branch names or fallback to remote HEAD
 function git_main_branch() {
   command git rev-parse --git-dir &>/dev/null || return
-  local ref
+  
+  local remote ref
+  
   for ref in refs/{heads,remotes/{origin,upstream}}/{main,trunk,mainline,default,stable,master}; do
     if command git show-ref -q --verify $ref; then
       echo ${ref:t}
@@ -42,6 +44,14 @@ function git_main_branch() {
     fi
   done
   
+  # Fallback: try to get the default branch from remote HEAD symbolic refs
+  for remote in origin upstream; do
+    ref=$(command git rev-parse --abbrev-ref $remote/HEAD 2>/dev/null)
+    if [[ $ref == $remote/* ]]; then
+      echo ${ref#"$remote/"}; return 0
+    fi
+  done
+
   # If no main branch was found, fall back to master but return error
   echo master
   return 1