gitclone: let errors on update propagate

Update use to tolerate errors in develop mode, to prevent buildout from
deleting develop working copies if anything happens, then this behavior was
extended to non-develop mode, apparently by mistake.

In non-develop mode, we want error to propagate, if something went wrong with
updating this repository, buildout should delete and retry.

slapos/recipe/build/tests.py

@@ -10,7 +10,7 @@ import zc.buildout.testing
 from zc.buildout.testing import buildoutTearDown
 from contextlib import contextmanager
 from functools import wraps
-from subprocess import check_call, check_output, CalledProcessError
+from subprocess import check_call, check_output, CalledProcessError, STDOUT
 from slapos.recipe.gitclone import GIT_CLONE_ERROR_MESSAGE, \
     GIT_CLONE_CACHE_ERROR_MESSAGE
 from slapos.recipe.downloadunpacked import make_read_only_recursively
@@ -492,6 +492,36 @@ repository = %s
   def test_ignore_cloning_submodules(self):
     self.test_clone_submodules_by_default(ignore_cloning_submodules=True)
 
+  @with_buildout
+  def test_reset_on_update_failure(self, buildout, sample_buildout, write, **kw):
+    self.createRepositoriesAndConnect()
+
+    write(sample_buildout, 'buildout.cfg',
+"""
+[buildout]
+parts = git-clone
+
+[git-clone]
+recipe = slapos.recipe.build:gitclone
+repository = %s
+""" % self.project_dir)
+    check_call([buildout])
+
+    check_call(
+        ['git', 'remote', 'add', 'broken', 'http://git.erp5.org/repos/nowhere'],
+        cwd=os.path.join(sample_buildout, "parts", "git-clone"))
+
+    with self.assertRaises(CalledProcessError) as output:
+      check_output([buildout], stderr=STDOUT)
+    self.assertIn(
+        b"error: Could not fetch broken",
+        output.exception.output)
+
+    # this reset repo
+    self.assertFalse(os.path.exists(os.path.join(sample_buildout, "parts", "git-clone")))
+    # and running buildout again succeeed
+    check_call([buildout])
+
 
 class MakeReadOnlyTests(unittest.TestCase):
 

slapos/recipe/gitclone.py

@@ -280,7 +280,7 @@ class Recipe(object):
     # If develop or revision parameter, no need to update
     if self.develop or self.revision:
       return
-    try:
+
     # first cleanup pyc files
     self.deletePycFiles(self.location)
 
@@ -300,12 +300,6 @@ class Recipe(object):
       check_call([self.git_command, 'submodule', 'update', '--init', '-f',
                   '--recursive'], cwd=self.location)
 
-    except:
-      # Buildout will remove the installed location and mark the part as not
-      # installed if an error occurs during update. If we are developping this
-      # repository we do not want this to happen.
-      print('Unable to update:\n%s' % traceback.format_exc())
-
 def uninstall(name, options):
   """Keep the working copy, unless develop is set to false.
   """