VC: CVS: Fix "Root" file parsing

The new "Root" file parsing has been based on CVS' documentation,
which gives the following format for *remote* repositories:
[:method:][[user][:password]@]hostname[:[port]]/pathname/to/repository
and for local ones:
:local:/pathname/to/repository
or
:local:c:/pathname/to/repository
or alternatively ':local:' replaced by ':fork:', or ':local:' omitted
when the path starts with a slash.

[The actual parsing code in CVS is actually a bit more restrictive.
See 'root.c'.]

Most notably, the previous version could not parse an absolute
pathname without an explicit :local: method or :pserver: lines with
passwords.

* lisp/vc/vc-cvs.el (vc-cvs-parse-root): Rewrite.

(vc-cvs-repository-hostname): Cope with `vc-cvs-parse-root' returning
an empty hostname (can only happen if the "Root" file is invalid),
returning nil in this case.

(vc-cvs-parse-uhp): Remove this standalone function formerly used only
by `vc-cvs-parse-root' and which doesn't allow correct parsing anyway.

* test/lisp/vc/vc-cvs-tests.el: New file, with tests for common "Root"
file content.

1 files changed, 107 insertions, 0 deletions

diff --git a/test/lisp/vc/vc-cvs-tests.el b/test/lisp/vc/vc-cvs-tests.el
new file mode 100644
index 00000000000..99ac9c8eb96
--- /dev/null
+++ b/test/lisp/vc/vc-cvs-tests.el
@@ -0,0 +1,107 @@
+;;; vc-cvs-tests.el --- tests for vc/vc-cvs.el  -*- lexical-binding:t -*-
+
+;; Copyright (C) 2023 Free Software Foundation, Inc.
+
+;; Author: Olivier Certner <olce.emacs@certner.fr>
+;; Maintainer: emacs-devel@gnu.org
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'vc-cvs)
+
+(ert-deftest vc-cvs-test-parse-root--local-no-method ()
+  (vc-cvs-test--check-parse-root
+   "/home/joe/repo"
+   '("local" nil nil "/home/joe/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--local-windows-drive-letter ()
+  (vc-cvs-test--check-parse-root
+   ":local:c:/users/joe/repo"
+   '("local" nil nil "c:/users/joe/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--ext-no-method-host-no-port-colon ()
+  (vc-cvs-test--check-parse-root
+   "host/home/serv/repo"
+   '("ext" nil "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--pserver-host-no-port-colon ()
+  (vc-cvs-test--check-parse-root
+   ":pserver:host/home/serv/repo"
+   '("pserver" nil "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--pserver-host-port-colon ()
+  (vc-cvs-test--check-parse-root
+   ":pserver:host:/home/serv/repo"
+   '("pserver" nil "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--ext-no-method-user-host-no-port-colon ()
+  (vc-cvs-test--check-parse-root
+   "usr@host/home/serv/repo"
+   '("ext" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--ext-no-method-user-host-port-colon ()
+  (vc-cvs-test--check-parse-root
+   "usr@host:/home/serv/repo"
+   '("ext" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--pserver-user-password-host-no-port-colon ()
+  (vc-cvs-test--check-parse-root
+   ":pserver:usr:passwd@host/home/serv/repo"
+   '("pserver" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--pserver-user-password-host-port-colon ()
+  (vc-cvs-test--check-parse-root
+   ":pserver:usr:passwd@host:/home/serv/repo"
+   '("pserver" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest vc-cvs-test-parse-root--pserver-user-password-host-port ()
+  (vc-cvs-test--check-parse-root
+   ":pserver:usr:passwd@host:28/home/serv/repo"
+   '("pserver" "usr" "host" "/home/serv/repo")))
+
+;; Next 3 tests are just to err on the side of caution. It doesn't
+;; seem that CVS 1.12 can ever produce such lines.
+
+(ert-deftest
+    vc-cvs-test-parse-root--ext-no-method-user-password-host-no-port-colon
+    ()
+  (vc-cvs-test--check-parse-root
+   "usr:passwd@host/home/serv/repo"
+   '("ext" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest
+    vc-cvs-test-parse-root--ext-no-method-user-password-host-port-colon
+    ()
+  (vc-cvs-test--check-parse-root
+   "usr:passwd@host:/home/serv/repo"
+   '("ext" "usr" "host" "/home/serv/repo")))
+
+(ert-deftest
+    vc-cvs-test-parse-root--ext-no-method-user-password-host-port
+    ()
+  (vc-cvs-test--check-parse-root
+   "usr:passwd@host:28/home/serv/repo"
+   '("ext" "usr" "host" "/home/serv/repo")))
+
+
+(defun vc-cvs-test--check-parse-root (input expected-output)
+  (should (equal (vc-cvs-parse-root input) expected-output)))
+
+;;; vc-cvs-tests.el ends here