Make branches and tags optional

Some svn repos don't have a branches dir or a tags dir in their layout.

This will for example allow us to lorry xmlto with the following lorry,

{
    "xmlto": {
        "type": "svn",
        "url": "http://svn.fedorahosted.org/svn/xmlto",
        "layout": {
            "trunk": "."
        }
    }
}

Change-Id: I74c032ab7642f4b22ed0569b2a163c0b78cba658

2 files changed, 28 insertions, 7 deletions

diff --git a/README b/README
index c9c116e..ad6cb9a 100644
--- a/README
+++ b/README
@@ -120,6 +120,7 @@ This is equivalent to
 Trunk is the path to the directory where the main branch is located.
 Branches and Tags are glob expressions to allow finer control over which paths
 are used.
+Trunk is mandatory, but Branches and Tags are optional.
 Texlive keeps a lot of resources in their svn repository, we are only concerned
 with the source code, so this layout should select the correct subdirectory for
 each branch.
diff --git a/lorry b/lorry
index aa87d52..2759f54 100755
--- a/lorry
+++ b/lorry
@@ -436,15 +436,35 @@ class Lorry(cliapp.Application):
         # git-svn will convert branch, trunk and tag paths to allow this,
         # but it is simpler to disable it and do it manually
         self.run_program(['git', 'config', 'svn-remote.svn.fetch',
-                          layout["trunk"]+':refs/heads/master'],
-                         cwd=gitdir)
-        self.run_program(['git', 'config', 'svn-remote.svn.branches',
-                          layout["branches"] + ':refs/heads/*'],
-                         cwd=gitdir)
-        self.run_program(['git', 'config', 'svn-remote.svn.tags',
-                          layout["tags"] + ':refs/tags/*'],
+                          layout["trunk"] + ':refs/heads/master'],
                          cwd=gitdir)
 
+        if 'branches' in layout:
+            self.run_program(['git', 'config', 'svn-remote.svn.branches',
+                             layout["branches"] + ':refs/heads/*'],
+                             cwd=gitdir)
+        else:
+            # try removing old config
+            try:
+                self.run_program(['git', 'config', '--unset',
+                                  'svn-remote.svn.branches'], cwd=gitdir)
+            except Exception as e:
+                if '(exit code 5)' not in e.message:
+                    raise
+
+        if 'tags' in layout:
+            self.run_program(['git', 'config', 'svn-remote.svn.tags',
+                             layout["tags"] + ':refs/tags/*'],
+                             cwd=gitdir)
+        else:
+            # try removing old config
+            try:
+                self.run_program(['git', 'config', '--unset',
+                                  'svn-remote.svn.tags'], cwd=gitdir)
+            except Exception as e:
+                if '(exit code 5)' not in e.message:
+                    raise
+
         # update the remote tracking branches
         self.run_program(['git', 'svn', 'fetch'], cwd=gitdir)