post_jump and pre_expand do not interact well #1579
Description
The problem
As for me, one of the main uses of pre_expand is to have a flexible number and layout of tabstops, while one of the main uses of post_jump is to perform actions while landing on a specific tabstop.
However, it looks like the numbered tabstops that pre_expand creates cannot be seen by post_jump functions, making it hard for the two to interact.
Indeed, they do not properly interact with the standard expanded snippet either, which might make for easier debugging.
Example 1
global !p
# creates some test placeholders
def test(trigger_length):
# deletes the trigger
cursorcol = snip.cursor[1]
snip.buffer[snip.line] = snip.buffer[snip.line][:cursorcol-trigger_length] + snip.buffer[snip.line][cursorcol:]
mystr = r'{$1} | {$2} | {$3} | $0'
snip.expand_anon(mystr)
return 0
endglobal
# creates some other placeholders
pre_expand "test(3)"
snippet try "try"
[$1] | [$2] | [$3] | $0
endsnippet
Expected behaviour
{[$1] | [$2] | [$3] | $0$1} | {$2} | {$3} | $0, in particular if I start typing text should appear in two places.
Actual behaviour
(something equivalent to) {[$1] | [$2] | [$3] | $4} | {$5} | {$6} | $0.
Example 2
global !p
# creates some test placeholders
def test(trigger_length):
# deletes the trigger
cursorcol = snip.cursor[1]
snip.buffer[snip.line] = snip.buffer[snip.line][:cursorcol-trigger_length] + snip.buffer[snip.line][cursorcol:]
mystr = r'{$1} | {$2} | {$3} | $0'
snip.expand_anon(mystr)
return 0
def del_useless_stop(delendum):
cursorcol = snip.cursor[1]
oldstring = snip.buffer[snip.line]
newstring = oldstring.replace(delendum, "")
snip.buffer[snip.line] = newstring
cursorcol -= len(oldstring)
cursorcol += len(newstring)
snip.cursor.set(snip.line, cursorcol)
endglobal
post_jump "if snip.tabstop == 0: del_useless_stop('{}')"
pre_expand "test(3)"
snippet try "try"
endsnippet
Expected behaviour
{$1} | {$2} | {$3} | $0, depending on whether or not something was written in the tabstops 1--3, the braces should be deleted when jumping to $0.
Indeed, this is the behaviour that one gets with the snippet
post_jump "if snip.tabstop == 0: del_useless_stop('{}')"
pre_expand "test(3)"
snippet try2 "try2"
{$1} | {$2} | {$3} | $0
endsnippet
Actual behaviour
Nothing happens when jumping to $0.