--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_merge_req_mercurial.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,171 @@
+#!/usr/bin/env python3
+
+# SàT plugin managing Mercurial VCS
+# Copyright (C) 2009-2021 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import re
+from twisted.python.procutils import which
+from libervia.backend.tools.common import async_process
+from libervia.backend.tools import utils
+from libervia.backend.core.i18n import _, D_
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core import exceptions
+from libervia.backend.core.log import getLogger
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "Mercurial Merge Request handler",
+    C.PI_IMPORT_NAME: "MERGE_REQUEST_MERCURIAL",
+    C.PI_TYPE: C.PLUG_TYPE_MISC,
+    C.PI_DEPENDENCIES: ["MERGE_REQUESTS"],
+    C.PI_MAIN: "MercurialHandler",
+    C.PI_HANDLER: "no",
+    C.PI_DESCRIPTION: _("""Merge request handler for Mercurial""")
+}
+
+SHORT_DESC = D_("handle Mercurial repository")
+CLEAN_RE = re.compile(r'[^\w -._]', flags=re.UNICODE)
+
+
+class MercurialProtocol(async_process.CommandProtocol):
+    """handle hg commands"""
+    name = "Mercurial"
+    command = None
+
+    @classmethod
+    def run(cls, path, command, *args, **kwargs):
+        """Create a new MercurialRegisterProtocol and execute the given mercurial command.
+
+        @param path(unicode): path to the repository
+        @param command(unicode): hg command to run
+        @return D(bytes): stdout of the command
+        """
+        assert "path" not in kwargs
+        kwargs["path"] = path
+        # FIXME: we have to use this workaround because Twisted's protocol.ProcessProtocol
+        #        is not using new style classes. This can be removed once moved to
+        #        Python 3 (super can be used normally then).
+        d = async_process.CommandProtocol.run.__func__(cls, command, *args, **kwargs)
+        d.addErrback(utils.logError)
+        return d
+
+
+class MercurialHandler(object):
+    data_types = ('mercurial_changeset',)
+
+    def __init__(self, host):
+        log.info(_("Mercurial merge request handler initialization"))
+        try:
+            MercurialProtocol.command = which('hg')[0]
+        except IndexError:
+            raise exceptions.NotFound(_("Mercurial executable (hg) not found, "
+                                        "can't use Mercurial handler"))
+        self.host = host
+        self._m = host.plugins['MERGE_REQUESTS']
+        self._m.register('mercurial', self, self.data_types, SHORT_DESC)
+
+
+    def check(self, repository):
+        d = MercurialProtocol.run(repository, 'identify')
+        d.addCallback(lambda __: True)
+        d.addErrback(lambda __: False)
+        return d
+
+    def export(self, repository):
+        d = MercurialProtocol.run(
+            repository, 'export', '-g', '-r', 'outgoing() and ancestors(.)',
+            '--encoding=utf-8'
+        )
+        d.addCallback(lambda data: data.decode('utf-8'))
+        return d
+
+    def import_(self, repository, data, data_type, item_id, service, node, extra):
+        parsed_data = self.parse(data)
+        try:
+            parsed_name = parsed_data[0]['commit_msg'].split('\n')[0]
+            parsed_name = CLEAN_RE.sub('', parsed_name)[:40]
+        except Exception:
+            parsed_name = ''
+        name = 'mr_{item_id}_{parsed_name}'.format(item_id=CLEAN_RE.sub('', item_id),
+                                                   parsed_name=parsed_name)
+        return MercurialProtocol.run(repository, 'qimport', '-g', '--name', name,
+                                     '--encoding=utf-8', '-', stdin=data)
+
+    def parse(self, data, data_type=None):
+        lines = data.splitlines()
+        total_lines = len(lines)
+        patches = []
+        while lines:
+            patch = {}
+            commit_msg = []
+            diff = []
+            state = 'init'
+            if lines[0] != '# HG changeset patch':
+                raise exceptions.DataError(_('invalid changeset signature'))
+            # line index of this patch in the whole data
+            patch_idx = total_lines - len(lines)
+            del lines[0]
+
+            for idx, line in enumerate(lines):
+                if state == 'init':
+                    if line.startswith('# '):
+                        if line.startswith('# User '):
+                            elems = line[7:].split()
+                            if not elems:
+                                continue
+                            last = elems[-1]
+                            if (last.startswith('<') and last.endswith('>')
+                                and '@' in last):
+                                patch[self._m.META_EMAIL] = elems.pop()[1:-1]
+                            patch[self._m.META_AUTHOR] = ' '.join(elems)
+                        elif line.startswith('# Date '):
+                            time_data = line[7:].split()
+                            if len(time_data) != 2:
+                                log.warning(_('unexpected time data: {data}')
+                                            .format(data=line[7:]))
+                                continue
+                            patch[self._m.META_TIMESTAMP] = (int(time_data[0])
+                                                             + int(time_data[1]))
+                        elif line.startswith('# Node ID '):
+                            patch[self._m.META_HASH] = line[10:]
+                        elif line.startswith('# Parent  '):
+                            patch[self._m.META_PARENT_HASH] = line[10:]
+                    else:
+                        state = 'commit_msg'
+                if state == 'commit_msg':
+                    if line.startswith('diff --git a/'):
+                        state = 'diff'
+                        patch[self._m.META_DIFF_IDX] = patch_idx + idx + 1
+                    else:
+                        commit_msg.append(line)
+                if state == 'diff':
+                    if line.startswith('# ') or idx == len(lines)-1:
+                        # a new patch is starting or we have reached end of patches
+                        if idx == len(lines)-1:
+                            # end of patches, we need to keep the line
+                            diff.append(line)
+                        patch[self._m.META_COMMIT_MSG] = '\n'.join(commit_msg)
+                        patch[self._m.META_DIFF] = '\n'.join(diff)
+                        patches.append(patch)
+                        if idx == len(lines)-1:
+                            del lines[:]
+                        else:
+                            del lines[:idx]
+                        break
+                    else:
+                        diff.append(line)
+        return patches