ignore long (block) comments when selecting buffer name

[?]

Jul 25, 2023, 10:34 PM

QM5V4K7DTRL24Y6HQXJXEZJLLJLO7ICVCOZW2AT76XATBUGA5WOAC

Dependencies

[2] SM7UNXQM avoid some unnecessary allocations
[3] BSDXVB3H backport some doc updates and renames
[4] AQRAWL63 don't tolerate Lua comments when parsing commands
[5] VA7NGQLG ignore comments when selecting buffer name
[*] LRDM35CE app running again

Change contents

replacement in live.lua at line 238

[3.219]→[2.38:199](∅→∅)

-- Return the first word, after skipping Lua comments.
if not buf:match('^%s*%-%-') then
return buf:match('^%s*(%S+)') -- avoid unnecessary allocations

[3.219]

[2.199]

return first_noncomment_word(buf)
end

-- return the first word (separated by whitespace) that's not in a Lua comment
-- or empty string if there's nothing
-- ignore strings; we don't expect them to be the first word in a program
function first_noncomment_word(str)
local pos = 1
while pos <= #str do -- not Unicode-aware; hopefully it doesn't need to be
if str:sub(pos,pos) == '-' then
-- skip any comments
if str:sub(pos+1,pos+1) == '-' then
-- definitely start of a comment
local long_comment_header = str:match('^%[=*%[', pos+2)
if long_comment_header then
-- long comment
local long_comment_trailer = long_comment_header:gsub('%[', ']')
pos = str:find(long_comment_trailer, pos, --[[plain]]true)
if pos == nil then return '' end -- incomplete comment; no first word
pos = pos + #long_comment_trailer
else
-- line comment
pos = str:find('\n', pos)
if pos == nil then return '' end -- incomplete comment; no first word
end
end
end
-- any non-whitespace that's not a comment is the first word
if str:sub(pos,pos):match('%s') then
pos = pos+1
else
return str:match('^%S*', pos)
end
replacement in live.lua at line 272

[2.205]→[2.205:359](∅→∅)

-- wastefully strip out comments everywhere, not just at the start
buf = buf:gsub('%-%-[^\n]*', '') -- line comments
return buf:match('^%s*(%S+)')

[2.205]

[3.970]

return ''
end

function test_first_noncomment_word()
check_eq(first_noncomment_word(''), '', 'empty string')
check_eq(first_noncomment_word('abc'), 'abc', 'single word')
check_eq(first_noncomment_word('abc def'), 'abc', 'stop at space')
check_eq(first_noncomment_word('abc\tdef'), 'abc', 'stop at tab')
check_eq(first_noncomment_word('abc\ndef'), 'abc', 'stop at newline')
check_eq(first_noncomment_word('-- abc\ndef'), 'def', 'ignore line comment')
check_eq(first_noncomment_word('--[[abc]] def'), 'def', 'ignore block comment')
check_eq(first_noncomment_word('--[[abc\n]] def'), 'def', 'ignore multi-line block comment')
check_eq(first_noncomment_word('--[[abc\n--]] def'), 'def', 'ignore comment leader before block comment trailer')
check_eq(first_noncomment_word('--[=[abc]=] def'), 'def', 'ignore long comment')
check_eq(first_noncomment_word('--[=[abc]] def ]=] ghi'), 'ghi', 'ignore long comment containing block comment trailer')
check_eq(first_noncomment_word('--[===[abc\n\ndef ghi\njkl]===]mno\npqr'), 'mno', 'ignore long comment containing block comment trailer')
check_eq(first_noncomment_word('-'), '-', 'incomplete comment token')
check_eq(first_noncomment_word('--abc'), '', 'incomplete line comment')
check_eq(first_noncomment_word('--abc\n'), '', 'just a line comment')
check_eq(first_noncomment_word('--abc\n '), '', 'just a line comment 2')
check_eq(first_noncomment_word('--[ab\n'), '', 'incomplete block comment token is a line comment')
check_eq(first_noncomment_word('--[[ab'), '', 'incomplete block comment')
check_eq(first_noncomment_word('--[[ab\n]'), '', 'incomplete block comment 2')
check_eq(first_noncomment_word('--[=[ab\n]] ]='), '', 'incomplete block comment 3')
check_eq(first_noncomment_word('--[=[ab\n]] ]=]'), '', 'just a block comment')
check_eq(first_noncomment_word('--[=[ab\n]] ]=] \n \n '), '', 'just a block comment 2')