Enable fetching git default branch dynamically instead of settings

GitHub.sublime-settings

@@ -45,5 +45,6 @@
 
     // The default branch to use when issuing Copy Remote URL to Clipboard, Open Remote URL in Browser, View, Blame,
     // History, or Edit commands
+    // Set to falsey values to fetch the current repo's default branch
     "default_branch": "main",
 }

sublime_github.py

@@ -9,6 +9,7 @@
 import plistlib
 import sublime
 import sublime_plugin
+import subprocess
 
 sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
 from github import GitHubApi
@@ -430,7 +431,32 @@ class RemoteUrlCommand(git.GitTextCommand):
         def run(self, edit):
             if self.branch == "default":
                 self.settings = sublime.load_settings("GitHub.sublime-settings")
-                branch = self.settings.get("default_branch")
+                default_branch_setting = self.settings.get("default_branch")
+
+                if default_branch_setting:
+                    branch = default_branch_setting
+                else:
+                    # Get the path of the currently opened file
+                    file_path = self.view.window().active_view().file_name()
+
+                    # Get the list of folders in the project
+                    folders = self.view.window().folders()
+
+                    top_level_folder = None
+                    for folder in folders:
+                        if file_path.startswith(folder):
+                            top_level_folder = folder
+                            break
+
+                    branch = (
+                        subprocess.check_output(
+                            "git -C %s symbolic-ref refs/remotes/origin/HEAD | sed 's@^refs/remotes/origin/@@'"%(top_level_folder),
+                            stderr=subprocess.STDOUT,
+                            shell=True,
+                        )
+                        .decode("utf-8")
+                        .strip()
+                    )
             else:
                 # Get the current remote branch--useful whether we want to link directly to that
                 # branch or to the branch's HEAD.