clone: simplifying dest repo creation
since creating a repo raises an exception if the repo already
exists, there's no need to try to create one.
add some test for repo creation when the destination exists
adding start
adding new
% new file
diff --git a/new b/new
new file mode 100644
--- /dev/null
+++ b/new
@@ -0,0 +1,1 @@
+new
% copy
diff --git a/new b/copy
copy from new
copy to copy
% rename
diff --git a/copy b/rename
rename from copy
rename to rename
% delete
diff --git a/rename b/rename
deleted file mode 100644
--- a/rename
+++ /dev/null
@@ -1,1 +0,0 @@
-new
adding src
% chmod 644
diff --git a/src b/src
old mode 100644
new mode 100755
% rename+mod+chmod
diff --git a/src b/dst
old mode 100755
new mode 100644
rename from src
rename to dst
--- a/dst
+++ b/dst
@@ -3,3 +3,4 @@ 3
3
4
5
+a