revlog: add a magic null revision to our index
We expand our index by one entry so that index[nullrev] points to a
unique entry, the null revision. This naturally eliminates numerous
extra tests in the performance-sensitive index access functions, most
of which are now trivial again.
Adding new entries is now done with insert(-1, e) rather than
append(e).
header = '{date|shortdate} {author|person} <{author|email}>\n\n'
header_verbose = ''
changeset = '\t* {files|stringify|fill68|tabindent}{desc|fill68|tabindent|strip}\n\t[{node|short}]{tags}\n\n'
changeset_quiet = '\t* {desc|firstline|fill68|tabindent|strip}\n\n'
changeset_verbose = '{date|isodate} {author|person} <{author|email}> ({node|short}{tags})\n\n\t* {file_adds|stringify|fill68|tabindent}{file_dels|stringify|fill68|tabindent}{files|stringify|fill68|tabindent}{desc|fill68|tabindent|strip}\n\n'
start_tags = ' ['
tag = '{tag}, '
last_tag = '{tag}]'
file = '{file}, '
last_file = '{file}:\n\t'
file_add = '{file_add}, '
last_file_add = '{file_add}: new file.\n* '
file_del = '{file_del}, '
last_file_del = '{file_del}: deleted file.\n* '