version: show enabled extensions (issue4209)

This code is based by hg-versions extension (GPLv2)
by Markus Zapke-Gruendemann <[e-mail]>


http://mercurial.selenic.com/wiki/VersionsExtension

mercurial/commands.py

@@ -14,6 +14,7 b' import hg, scmutil, util, revlog, copies'
 import patch, help, encoding, templatekw, discovery
 import archival, changegroup, cmdutil, hbisect
 import sshserver, hgweb, commandserver
+import extensions
 from hgweb import server as hgweb_server
 import merge as mergemod
 import minirst, revset, fileset
@@ -6016,3 +6017,15 b' def version_(ui):'
         "There is NO\nwarranty; "
         "not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.\n"
     ))
+
+    ui.note(_("\nEnabled extensions:\n\n"))
+    if ui.verbose:
+        # format names and versions into columns
+        names = []
+        vers = []
+        for name, module in extensions.extensions():
+            names.append(name)
+            vers.append(extensions.moduleversion(module))
+        maxnamelen = max(len(n) for n in names)
+        for i, name in enumerate(names):
+            ui.write("  %-*s  %s\n" % (maxnamelen, name, vers[i]))

mercurial/extensions.py

@@ -367,3 +367,16 b' def enabled(shortname=True):'
         exts[ename] = doc.splitlines()[0].strip()
 
     return exts
+
+def moduleversion(module):
+    '''return version information from given module as a string'''
+    if (util.safehasattr(module, 'getversion')
+          and callable(module.getversion)):
+        version = module.getversion()
+    elif util.safehasattr(module, '__version__'):
+        version = module.__version__
+    else:
+        version = ''
+    if isinstance(version, (list, tuple)):
+        version = '.'.join(str(o) for o in version)
+    return version