build.cmds.CmdListRepos: Support local repos

Make jw-projects.py list-repos support a local directory as base URL
of all git repositories, notably used by PROJECTS_DIR_REMOTE_BASE,
which can now point to a local directory.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/build/cmds/CmdListRepos.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-import re
+import re, git, os
 from argparse import Namespace, ArgumentParser
 
 from ..Cmd import Cmd
@@ -74,4 +74,18 @@ class CmdListRepos(Cmd): # export
                     for repo in repos:
                         print(repo['name'])
                     return
+        if os.path.isdir(args.base_url):
+            for subdir in ["." , args.from_user]:
+                out = []
+                for entry in os.scandir(args.base_url + "/" + subdir):
+                    path = entry.path
+                    try:
+                        _ = git.Repo(path).git_dir
+                    except:
+                        continue
+                    out.append(path)
+                if out:
+                    print('\n'.join(out))
+                    break
+            return
         raise Exception(f'Don\'t know how to enumerate Git repos at base url {args.base_url}')