commands: call ui.username carefully in debuginstall

After c63c336ee2f7, 'hg debuginstall' would abort halfway through if
no username was set. We now catch and display the exception instead.

mercurial/commands.py

@@ -1029,15 +1029,12 b' def debuginstall(ui):'
 
     # check username
     ui.status(_("Checking username...\n"))
-    user = os.environ.get("HGUSER")
-    if user is None:
-        user = ui.config("ui", "username")
-    if user is None:
-        user = os.environ.get("EMAIL")
-    if not user:
-        ui.warn(" ")
-        ui.username()
+    try:
+        user = ui.username()
+    except util.Abort, e:
+        ui.write(" %s\n" % e)
         ui.write(_(" (specify a username in your .hgrc file)\n"))
+        problems += 1
 
     if not problems:
         ui.status(_("No problems detected\n"))

tests/test-install

@@ -1,3 +1,10 b''
 #!/bin/sh
 
+echo '% hg debuginstall'
 hg debuginstall
+
+echo '% hg debuginstall with no username'
+HGUSER= hg debuginstall
+
+# Happy End
+true

tests/test-install.out

@@ -1,3 +1,4 b''
+% hg debuginstall
 Checking encoding (ascii)...
 Checking extensions...
 Checking templates...
@@ -5,3 +6,13 b' Checking patch...'
 Checking commit editor...
 Checking username...
 No problems detected
+% hg debuginstall with no username
+Checking encoding (ascii)...
+Checking extensions...
+Checking templates...
+Checking patch...
+Checking commit editor...
+Checking username...
+ Please specify a username.
+ (specify a username in your .hgrc file)
+1 problems detected, please check your install!