templater: factor out function that creates templater from string template
This function will host loading of template aliases. It is not defined at
templater, but at formatter, since formatter is the module handling ui stuff
in front of templater.
$ hg init
$ echo 0 > a
$ echo 0 > b
$ hg ci -A -m m
adding a
adding b
$ hg rm a
$ hg cat a
0
$ hg cat --decode a # more tests in test-encode
0
$ echo 1 > b
$ hg ci -m m
$ echo 2 > b
$ hg cat -r 0 a
0
$ hg cat -r 0 b
0
$ hg cat -r 1 a
a: no such file in rev 7040230c159c
[1]
$ hg cat -r 1 b
1
Test multiple files
$ echo 3 > c
$ hg ci -Am addmore c
$ hg cat b c
1
3
$ hg cat .
1
3
$ hg cat . c
1
3
Test fileset
$ hg cat 'set:not(b) or a'
3
$ hg cat 'set:c or b'
1
3
$ mkdir tmp
$ hg cat --output tmp/HH_%H c
$ hg cat --output tmp/RR_%R c
$ hg cat --output tmp/h_%h c
$ hg cat --output tmp/r_%r c
$ hg cat --output tmp/%s_s c
$ hg cat --output tmp/%d%%_d c
$ hg cat --output tmp/%p_p c
$ hg log -r . --template "{rev}: {node|short}\n"
2: 45116003780e
$ find tmp -type f | sort
tmp/.%_d
tmp/HH_45116003780e3678b333fb2c99fa7d559c8457e9
tmp/RR_2
tmp/c_p
tmp/c_s
tmp/h_45116003780e
tmp/r_2
Test working directory
$ echo b-wdir > b
$ hg cat -r 'wdir()' b
b-wdir