It can append that when we try to access a Mercurial repository we got the following error:
abort: requirement 'fncache' not supported!
It append when a "too old" version of Mercurial is used. Indeed, from version
1.1, Mercurial used a new repository format (
fncache), which is no more readable
by the former versions. The reverse is not true, and newer version are able to
read old repositories.
To solve the problem we can use a version of Mercurial able to read the two type of repository and convert it to the old format using the following command:
hg --config format.usefncache=0 clone --pull A B
A the initial repository and
B the converted repository.
To completely deactivate the new repository format, a modification the
configuration file of Mercurial is needed (
[format] usefncache = False