diff options
Diffstat (limited to 'runtime/indent/erlang.vim')
| -rw-r--r-- | runtime/indent/erlang.vim | 1536 |
1 files changed, 1536 insertions, 0 deletions
diff --git a/runtime/indent/erlang.vim b/runtime/indent/erlang.vim new file mode 100644 index 0000000..7aa3858 --- /dev/null +++ b/runtime/indent/erlang.vim @@ -0,0 +1,1536 @@ +" Vim indent file +" Language: Erlang (http://www.erlang.org) +" Author: Csaba Hoch <csaba.hoch@gmail.com> +" Contributors: Edwin Fine <efine145_nospam01 at usa dot net> +" Pawel 'kTT' Salata <rockplayer.pl@gmail.com> +" Ricardo Catalinas Jiménez <jimenezrick@gmail.com> +" Last Update: 2022-Sep-06 +" License: Vim license +" URL: https://github.com/vim-erlang/vim-erlang-runtime + +" Note About Usage: +" This indentation script works best with the Erlang syntax file created by +" Kreąimir Marľić (Kresimir Marzic) and maintained by Csaba Hoch. + +" Notes About Implementation: +" +" - LTI = Line to indent. +" - The index of the first line is 1, but the index of the first column is 0. + + +" Initialization {{{1 +" ============== + +" Only load this indent file when no other was loaded +" Vim 7 or later is needed +if exists("b:did_indent") || version < 700 + finish +else + let b:did_indent = 1 +endif + +setlocal indentexpr=ErlangIndent() +setlocal indentkeys+=0=end,0=of,0=catch,0=after,0=else,0=when,0=),0=],0=},0=>> + +let b:undo_indent = "setl inde< indk<" + +" Only define the functions once +if exists("*ErlangIndent") + finish +endif + +let s:cpo_save = &cpo +set cpo&vim + +" Logging library {{{1 +" =============== + +" Purpose: +" Logs the given string using the ErlangIndentLog function if it exists. +" Parameters: +" s: string +function! s:Log(s) + if exists("*ErlangIndentLog") + call ErlangIndentLog(a:s) + endif +endfunction + +" Line tokenizer library {{{1 +" ====================== + +" Indtokens are "indentation tokens". See their exact format in the +" documentation of the s:GetTokensFromLine function. + +" Purpose: +" Calculate the new virtual column after the given segment of a line. +" Parameters: +" line: string +" first_index: integer -- the index of the first character of the segment +" last_index: integer -- the index of the last character of the segment +" vcol: integer -- the virtual column of the first character of the token +" tabstop: integer -- the value of the 'tabstop' option to be used +" Returns: +" vcol: integer +" Example: +" " index: 0 12 34567 +" " vcol: 0 45 89 +" s:CalcVCol("\t'\tx', b", 1, 4, 4) -> 10 +function! s:CalcVCol(line, first_index, last_index, vcol, tabstop) + + " We copy the relevant segment of the line, otherwise if the line were + " e.g. `"\t", term` then the else branch below would consume the `", term` + " part at once. + let line = a:line[a:first_index : a:last_index] + + let i = 0 + let last_index = a:last_index - a:first_index + let vcol = a:vcol + + while 0 <= i && i <= last_index + + if line[i] ==# "\t" + " Example (when tabstop == 4): + " + " vcol + tab -> next_vcol + " 0 + tab -> 4 + " 1 + tab -> 4 + " 2 + tab -> 4 + " 3 + tab -> 4 + " 4 + tab -> 8 + " + " next_i - i == the number of tabs + let next_i = matchend(line, '\t*', i + 1) + let vcol = (vcol / a:tabstop + (next_i - i)) * a:tabstop + call s:Log('new vcol after tab: '. vcol) + else + let next_i = matchend(line, '[^\t]*', i + 1) + let vcol += next_i - i + call s:Log('new vcol after other: '. vcol) + endif + let i = next_i + endwhile + + return vcol +endfunction + +" Purpose: +" Go through the whole line and return the tokens in the line. +" Parameters: +" line: string -- the line to be examined +" string_continuation: bool +" atom_continuation: bool +" Returns: +" indtokens = [indtoken] +" indtoken = [token, vcol, col] +" token = string (examples: 'begin', '<quoted_atom>', '}') +" vcol = integer (the virtual column of the first character of the token; +" counting starts from 0) +" col = integer (counting starts from 0) +function! s:GetTokensFromLine(line, string_continuation, atom_continuation, + \tabstop) + + let linelen = strlen(a:line) " The length of the line + let i = 0 " The index of the current character in the line + let vcol = 0 " The virtual column of the current character + let indtokens = [] + + if a:string_continuation + let i = matchend(a:line, '^\%([^"\\]\|\\.\)*"', 0) + if i ==# -1 + call s:Log(' Whole line is string continuation -> ignore') + return [] + else + let vcol = s:CalcVCol(a:line, 0, i - 1, 0, a:tabstop) + call add(indtokens, ['<string_end>', vcol, i]) + endif + elseif a:atom_continuation + let i = matchend(a:line, "^\\%([^'\\\\]\\|\\\\.\\)*'", 0) + if i ==# -1 + call s:Log(' Whole line is quoted atom continuation -> ignore') + return [] + else + let vcol = s:CalcVCol(a:line, 0, i - 1, 0, a:tabstop) + call add(indtokens, ['<quoted_atom_end>', vcol, i]) + endif + endif + + while 0 <= i && i < linelen + + let next_vcol = '' + + " Spaces + if a:line[i] ==# ' ' + let next_i = matchend(a:line, ' *', i + 1) + + " Tabs + elseif a:line[i] ==# "\t" + let next_i = matchend(a:line, '\t*', i + 1) + + " See example in s:CalcVCol + let next_vcol = (vcol / a:tabstop + (next_i - i)) * a:tabstop + + " Comment + elseif a:line[i] ==# '%' + let next_i = linelen + + " String token: "..." + elseif a:line[i] ==# '"' + let next_i = matchend(a:line, '\%([^"\\]\|\\.\)*"', i + 1) + if next_i ==# -1 + call add(indtokens, ['<string_start>', vcol, i]) + else + let next_vcol = s:CalcVCol(a:line, i, next_i - 1, vcol, a:tabstop) + call add(indtokens, ['<string>', vcol, i]) + endif + + " Quoted atom token: '...' + elseif a:line[i] ==# "'" + let next_i = matchend(a:line, "\\%([^'\\\\]\\|\\\\.\\)*'", i + 1) + if next_i ==# -1 + call add(indtokens, ['<quoted_atom_start>', vcol, i]) + else + let next_vcol = s:CalcVCol(a:line, i, next_i - 1, vcol, a:tabstop) + call add(indtokens, ['<quoted_atom>', vcol, i]) + endif + + " Keyword or atom or variable token or number + elseif a:line[i] =~# '[a-zA-Z_@0-9]' + let next_i = matchend(a:line, + \'[[:alnum:]_@:]*\%(\s*#\s*[[:alnum:]_@:]*\)\=', + \i + 1) + call add(indtokens, [a:line[(i):(next_i - 1)], vcol, i]) + + " Character token: $<char> (as in: $a) + elseif a:line[i] ==# '$' + call add(indtokens, ['$.', vcol, i]) + let next_i = i + 2 + + " Dot token: . + elseif a:line[i] ==# '.' + + let next_i = i + 1 + + if i + 1 ==# linelen || a:line[i + 1] =~# '[[:blank:]%]' + " End of clause token: . (as in: f() -> ok.) + call add(indtokens, ['<end_of_clause>', vcol, i]) + + else + " Possibilities: + " - Dot token in float: . (as in: 3.14) + " - Dot token in record: . (as in: #myrec.myfield) + call add(indtokens, ['.', vcol, i]) + endif + + " Equal sign + elseif a:line[i] ==# '=' + " This is handled separately so that "=<<" will be parsed as + " ['=', '<<'] instead of ['=<', '<']. Although Erlang parses it + " currently in the latter way, that may be fixed some day. + call add(indtokens, [a:line[i], vcol, i]) + let next_i = i + 1 + + " Three-character tokens + elseif i + 1 < linelen && + \ index(['=:=', '=/='], a:line[i : i + 1]) != -1 + call add(indtokens, [a:line[i : i + 1], vcol, i]) + let next_i = i + 2 + + " Two-character tokens + elseif i + 1 < linelen && + \ index(['->', '<<', '>>', '||', '==', '/=', '=<', '>=', '?=', '++', + \ '--', '::'], + \ a:line[i : i + 1]) != -1 + call add(indtokens, [a:line[i : i + 1], vcol, i]) + let next_i = i + 2 + + " Other character: , ; < > ( ) [ ] { } # + - * / : ? = ! | + else + call add(indtokens, [a:line[i], vcol, i]) + let next_i = i + 1 + + endif + + if next_vcol ==# '' + let vcol += next_i - i + else + let vcol = next_vcol + endif + + let i = next_i + + endwhile + + return indtokens + +endfunction + +" TODO: doc, handle "not found" case +function! s:GetIndtokenAtCol(indtokens, col) + let i = 0 + while i < len(a:indtokens) + if a:indtokens[i][2] ==# a:col + return [1, i] + elseif a:indtokens[i][2] > a:col + return [0, s:IndentError('No token at col ' . a:col . ', ' . + \'indtokens = ' . string(a:indtokens), + \'', '')] + endif + let i += 1 + endwhile + return [0, s:IndentError('No token at col ' . a:col . ', ' . + \'indtokens = ' . string(a:indtokens), + \'', '')] +endfunction + +" Stack library {{{1 +" ============= + +" Purpose: +" Push a token onto the parser's stack. +" Parameters: +" stack: [token] +" token: string +function! s:Push(stack, token) + call s:Log(' Stack Push: "' . a:token . '" into ' . string(a:stack)) + call insert(a:stack, a:token) +endfunction + +" Purpose: +" Pop a token from the parser's stack. +" Parameters: +" stack: [token] +" token: string +" Returns: +" token: string -- the removed element +function! s:Pop(stack) + let head = remove(a:stack, 0) + call s:Log(' Stack Pop: "' . head . '" from ' . string(a:stack)) + return head +endfunction + +" Library for accessing and storing tokenized lines {{{1 +" ================================================= + +" The Erlang token cache: an `lnum -> indtokens` dictionary that stores the +" tokenized lines. +let s:all_tokens = {} +let s:file_name = '' +let s:last_changedtick = -1 + +" Purpose: +" Clear the Erlang token cache if we have a different file or the file has +" been changed since the last indentation. +function! s:ClearTokenCacheIfNeeded() + let file_name = expand('%:p') + if file_name != s:file_name || + \ b:changedtick != s:last_changedtick + let s:file_name = file_name + let s:last_changedtick = b:changedtick + let s:all_tokens = {} + endif +endfunction + +" Purpose: +" Return the tokens of line `lnum`, if that line is not empty. If it is +" empty, find the first non-empty line in the given `direction` and return +" the tokens of that line. +" Parameters: +" lnum: integer +" direction: 'up' | 'down' +" Returns: +" result: [] -- the result is an empty list if we hit the beginning or end +" of the file +" | [lnum, indtokens] +" lnum: integer -- the index of the non-empty line that was found and +" tokenized +" indtokens: [indtoken] -- the tokens of line `lnum` +function! s:TokenizeLine(lnum, direction) + + call s:Log('Tokenizing starts from line ' . a:lnum) + if a:direction ==# 'up' + let lnum = prevnonblank(a:lnum) + else " a:direction ==# 'down' + let lnum = nextnonblank(a:lnum) + endif + + " We hit the beginning or end of the file + if lnum ==# 0 + let indtokens = [] + call s:Log(' We hit the beginning or end of the file.') + + " The line has already been parsed + elseif has_key(s:all_tokens, lnum) + let indtokens = s:all_tokens[lnum] + call s:Log('Cached line ' . lnum . ': ' . getline(lnum)) + call s:Log(" Tokens in the line:\n - " . join(indtokens, "\n - ")) + + " The line should be parsed now + else + + " Parse the line + let line = getline(lnum) + let string_continuation = s:IsLineStringContinuation(lnum) + let atom_continuation = s:IsLineAtomContinuation(lnum) + let indtokens = s:GetTokensFromLine(line, string_continuation, + \atom_continuation, &tabstop) + let s:all_tokens[lnum] = indtokens + call s:Log('Tokenizing line ' . lnum . ': ' . line) + call s:Log(" Tokens in the line:\n - " . join(indtokens, "\n - ")) + + endif + + return [lnum, indtokens] +endfunction + +" Purpose: +" As a helper function for PrevIndToken and NextIndToken, the FindIndToken +" function finds the first line with at least one token in the given +" direction. +" Parameters: +" lnum: integer +" direction: 'up' | 'down' +" Returns: +" result: [[], 0, 0] +" -- the result is an empty list if we hit the beginning or end of +" the file +" | [indtoken, lnum, i] +" -- the content, lnum and token index of the next (or previous) +" indtoken +function! s:FindIndToken(lnum, dir) + let lnum = a:lnum + while 1 + let lnum += (a:dir ==# 'up' ? -1 : 1) + let [lnum, indtokens] = s:TokenizeLine(lnum, a:dir) + if lnum ==# 0 + " We hit the beginning or end of the file + return [[], 0, 0] + elseif !empty(indtokens) + " We found a non-empty line. If we were moving up, we return the last + " token of this line. Otherwise we return the first token if this line. + let i = (a:dir ==# 'up' ? len(indtokens) - 1 : 0) + return [indtokens[i], lnum, i] + endif + endwhile +endfunction + +" Purpose: +" Find the token that directly precedes the given token. +" Parameters: +" lnum: integer -- the line of the given token +" i: the index of the given token within line `lnum` +" Returns: +" result = [] -- the result is an empty list if the given token is the first +" token of the file +" | indtoken +function! s:PrevIndToken(lnum, i) + call s:Log(' PrevIndToken called: lnum=' . a:lnum . ', i =' . a:i) + + " If the current line has a previous token, return that + if a:i > 0 + return [s:all_tokens[a:lnum][a:i - 1], a:lnum, a:i - 1] + else + return s:FindIndToken(a:lnum, 'up') + endif +endfunction + +" Purpose: +" Find the token that directly succeeds the given token. +" Parameters: +" lnum: integer -- the line of the given token +" i: the index of the given token within line `lnum` +" Returns: +" result = [] -- the result is an empty list if the given token is the last +" token of the file +" | indtoken +function! s:NextIndToken(lnum, i) + call s:Log(' NextIndToken called: lnum=' . a:lnum . ', i =' . a:i) + + " If the current line has a next token, return that + if len(s:all_tokens[a:lnum]) > a:i + 1 + return [s:all_tokens[a:lnum][a:i + 1], a:lnum, a:i + 1] + else + return s:FindIndToken(a:lnum, 'down') + endif +endfunction + +" ErlangCalcIndent helper functions {{{1 +" ================================= + +" Purpose: +" This function is called when the parser encounters a syntax error. +" +" If we encounter a syntax error, we return +" g:erlang_unexpected_token_indent, which is -1 by default. This means that +" the indentation of the LTI will not be changed. +" Parameter: +" msg: string +" token: string +" stack: [token] +" Returns: +" indent: integer +function! s:IndentError(msg, token, stack) + call s:Log('Indent error: ' . a:msg . ' -> return') + call s:Log(' Token = ' . a:token . ', ' . + \' stack = ' . string(a:stack)) + return g:erlang_unexpected_token_indent +endfunction + +" Purpose: +" This function is called when the parser encounters an unexpected token, +" and the parser will return the number given back by UnexpectedToken. +" +" If we encounter an unexpected token, we return +" g:erlang_unexpected_token_indent, which is -1 by default. This means that +" the indentation of the LTI will not be changed. +" Parameter: +" token: string +" stack: [token] +" Returns: +" indent: integer +function! s:UnexpectedToken(token, stack) + call s:Log(' Unexpected token ' . a:token . ', stack = ' . + \string(a:stack) . ' -> return') + return g:erlang_unexpected_token_indent +endfunction + +if !exists('g:erlang_unexpected_token_indent') + let g:erlang_unexpected_token_indent = -1 +endif + +" Purpose: +" Return whether the given line starts with a string continuation. +" Parameter: +" lnum: integer +" Returns: +" result: bool +" Example: +" f() -> % IsLineStringContinuation = false +" "This is a % IsLineStringContinuation = false +" multiline % IsLineStringContinuation = true +" string". % IsLineStringContinuation = true +function! s:IsLineStringContinuation(lnum) + if has('syntax_items') + return synIDattr(synID(a:lnum, 1, 0), 'name') =~# '^erlangString' + else + return 0 + endif +endfunction + +" Purpose: +" Return whether the given line starts with an atom continuation. +" Parameter: +" lnum: integer +" Returns: +" result: bool +" Example: +" 'function with % IsLineAtomContinuation = true, but should be false +" weird name'() -> % IsLineAtomContinuation = true +" ok. % IsLineAtomContinuation = false +function! s:IsLineAtomContinuation(lnum) + if has('syntax_items') + let syn_name = synIDattr(synID(a:lnum, 1, 0), 'name') + return syn_name =~# '^erlangQuotedAtom' || + \ syn_name =~# '^erlangQuotedRecord' + else + return 0 + endif +endfunction + +" Purpose: +" Return whether the 'catch' token (which should be the `i`th token in line +" `lnum`) is standalone or part of a try-catch block, based on the preceding +" token. +" Parameters: +" lnum: integer +" i: integer +" Return: +" is_standalone: bool +function! s:IsCatchStandalone(lnum, i) + call s:Log(' IsCatchStandalone called: lnum=' . a:lnum . ', i=' . a:i) + let [prev_indtoken, _, _] = s:PrevIndToken(a:lnum, a:i) + + " If we hit the beginning of the file, it is not a catch in a try block + if prev_indtoken == [] + return 1 + endif + + let prev_token = prev_indtoken[0] + + if prev_token =~# '^[A-Z_@0-9]' + let is_standalone = 0 + elseif prev_token =~# '[a-z]' + if index(['after', 'and', 'andalso', 'band', 'begin', 'bnot', 'bor', 'bsl', + \ 'bsr', 'bxor', 'case', 'catch', 'div', 'maybe', 'not', 'or', + \ 'orelse', 'rem', 'try', 'xor'], prev_token) != -1 + " If catch is after these keywords, it is standalone + let is_standalone = 1 + else + " If catch is after another keyword (e.g. 'end') or an atom, it is + " part of try-catch. + " + " Keywords: + " - may precede 'catch': end + " - may not precede 'catch': else fun if of receive when + " - unused: cond let query + let is_standalone = 0 + endif + elseif index([')', ']', '}', '<string>', '<string_end>', '<quoted_atom>', + \ '<quoted_atom_end>', '$.'], prev_token) != -1 + let is_standalone = 0 + else + " This 'else' branch includes the following tokens: + " -> == /= =< < >= > ?= =:= =/= + - * / ++ -- :: < > ; ( [ { ? = ! . | + let is_standalone = 1 + endif + + call s:Log(' "catch" preceded by "' . prev_token . '" -> catch ' . + \(is_standalone ? 'is standalone' : 'belongs to try-catch')) + return is_standalone + +endfunction + +" Purpose: +" This function is called when a begin-type element ('begin', 'case', +" '[', '<<', etc.) is found. It asks the caller to return if the stack +" if already empty. +" Parameters: +" stack: [token] +" token: string +" curr_vcol: integer +" stored_vcol: integer +" sw: integer -- number of spaces to be used after the begin element as +" indentation +" Returns: +" result: [should_return, indent] +" should_return: bool -- if true, the caller should return `indent` to Vim +" indent -- integer +function! s:BeginElementFoundIfEmpty(stack, token, curr_vcol, stored_vcol, sw) + if empty(a:stack) + if a:stored_vcol ==# -1 + call s:Log(' "' . a:token . '" directly precedes LTI -> return') + return [1, a:curr_vcol + a:sw] + else + call s:Log(' "' . a:token . + \'" token (whose expression includes LTI) found -> return') + return [1, a:stored_vcol] + endif + else + return [0, 0] + endif +endfunction + +" Purpose: +" This function is called when a begin-type element ('begin', 'case', '[', +" '<<', etc.) is found, and in some cases when 'after' and 'when' is found. +" It asks the caller to return if the stack is already empty. +" Parameters: +" stack: [token] +" token: string +" curr_vcol: integer +" stored_vcol: integer +" end_token: end token that belongs to the begin element found (e.g. if the +" begin element is 'begin', the end token is 'end') +" sw: integer -- number of spaces to be used after the begin element as +" indentation +" Returns: +" result: [should_return, indent] +" should_return: bool -- if true, the caller should return `indent` to Vim +" indent -- integer +function! s:BeginElementFound(stack, token, curr_vcol, stored_vcol, end_token, sw) + + " Return 'return' if the stack is empty + let [ret, res] = s:BeginElementFoundIfEmpty(a:stack, a:token, a:curr_vcol, + \a:stored_vcol, a:sw) + if ret | return [ret, res] | endif + + if a:stack[0] ==# a:end_token + call s:Log(' "' . a:token . '" pops "' . a:end_token . '"') + call s:Pop(a:stack) + if !empty(a:stack) && a:stack[0] ==# 'align_to_begin_element' + call s:Pop(a:stack) + if empty(a:stack) + return [1, a:curr_vcol] + else + return [1, s:UnexpectedToken(a:token, a:stack)] + endif + else + return [0, 0] + endif + else + return [1, s:UnexpectedToken(a:token, a:stack)] + endif +endfunction + +" Purpose: +" This function is called when we hit the beginning of a file or an +" end-of-clause token -- i.e. when we found the beginning of the current +" clause. +" +" If the stack contains an '->' or 'when', this means that we can return +" now, since we were looking for the beginning of the clause. +" Parameters: +" stack: [token] +" token: string +" stored_vcol: integer +" lnum: the line number of the "end of clause" mark (or 0 if we hit the +" beginning of the file) +" i: the index of the "end of clause" token within its own line +" Returns: +" result: [should_return, indent] +" should_return: bool -- if true, the caller should return `indent` to Vim +" indent -- integer +function! s:BeginningOfClauseFound(stack, token, stored_vcol, lnum, i) + if !empty(a:stack) && a:stack[0] ==# 'when' + call s:Log(' BeginningOfClauseFound: "when" found in stack') + call s:Pop(a:stack) + if empty(a:stack) + call s:Log(' Stack is ["when"], so LTI is in a guard -> return') + return [1, a:stored_vcol + shiftwidth() + 2] + else + return [1, s:UnexpectedToken(a:token, a:stack)] + endif + elseif !empty(a:stack) && a:stack[0] ==# '->' + call s:Log(' BeginningOfClauseFound: "->" found in stack') + call s:Pop(a:stack) + if empty(a:stack) + call s:Log(' Stack is ["->"], so LTI is in function body -> return') + return [1, a:stored_vcol + shiftwidth()] + elseif a:stack[0] ==# ';' + call s:Pop(a:stack) + + if !empty(a:stack) + return [1, s:UnexpectedToken(a:token, a:stack)] + endif + + if a:lnum ==# 0 + " Set lnum and i to be NextIndToken-friendly + let lnum = 1 + let i = -1 + else + let lnum = a:lnum + let i = a:i + endif + + " Are we after a "-spec func() ...;" clause? + let [next1_indtoken, next1_lnum, next1_i] = s:NextIndToken(lnum, i) + if !empty(next1_indtoken) && next1_indtoken[0] =~# '-' + let [next2_indtoken, next2_lnum, next2_i] = + \s:NextIndToken(next1_lnum, next1_i) + if !empty(next2_indtoken) && next2_indtoken[0] =~# 'spec' + let [next3_indtoken, next3_lnum, next3_i] = + \s:NextIndToken(next2_lnum, next2_i) + if !empty(next3_indtoken) + let [next4_indtoken, next4_lnum, next4_i] = + \s:NextIndToken(next3_lnum, next3_i) + if !empty(next4_indtoken) + " Yes, we are. + call s:Log(' Stack is ["->", ";"], so LTI is in a "-spec" ' . + \'attribute -> return') + return [1, next4_indtoken[1]] + endif + endif + endif + endif + + call s:Log(' Stack is ["->", ";"], so LTI is in a function head ' . + \'-> return') + return [1, a:stored_vcol] + + else + return [1, s:UnexpectedToken(a:token, a:stack)] + endif + else + return [0, 0] + endif +endfunction + +let g:erlang_indent_searchpair_timeout = 2000 + +" TODO +function! s:SearchPair(lnum, curr_col, start, middle, end) + call cursor(a:lnum, a:curr_col + 1) + let [lnum_new, col1_new] = + \searchpairpos(a:start, a:middle, a:end, 'bW', + \'synIDattr(synID(line("."), col("."), 0), "name") ' . + \'=~? "string\\|quotedatom\\|todo\\|comment\\|' . + \'erlangmodifier"', + \0, g:erlang_indent_searchpair_timeout) + return [lnum_new, col1_new - 1] +endfunction + +function! s:SearchEndPair(lnum, curr_col) + return s:SearchPair( + \ a:lnum, a:curr_col, + \ '\C\<\%(case\|try\|begin\|receive\|if\|maybe\)\>\|' . + \ '\<fun\>\%(\s\|\n\|%.*$\|[A-Z_@][a-zA-Z_@]*\)*(', + \ '', + \ '\<end\>') +endfunction + +" ErlangCalcIndent {{{1 +" ================ + +" Purpose: +" Calculate the indentation of the given line. +" Parameters: +" lnum: integer -- index of the line for which the indentation should be +" calculated +" stack: [token] -- initial stack +" Return: +" indent: integer -- if -1, that means "don't change the indentation"; +" otherwise it means "indent the line with `indent` +" number of spaces or equivalent tabs" +function! s:ErlangCalcIndent(lnum, stack) + let res = s:ErlangCalcIndent2(a:lnum, a:stack) + call s:Log("ErlangCalcIndent returned: " . res) + return res +endfunction + +function! s:ErlangCalcIndent2(lnum, stack) + + let lnum = a:lnum + let stored_vcol = -1 " Virtual column of the first character of the token that + " we currently think we might align to. + let mode = 'normal' + let stack = a:stack + let semicolon_abscol = '' + + " Walk through the lines of the buffer backwards (starting from the + " previous line) until we can decide how to indent the current line. + while 1 + + let [lnum, indtokens] = s:TokenizeLine(lnum, 'up') + + " Hit the start of the file + if lnum ==# 0 + let [ret, res] = s:BeginningOfClauseFound(stack, 'beginning_of_file', + \stored_vcol, 0, 0) + if ret | return res | endif + + return 0 + endif + + let i = len(indtokens) - 1 + let last_token_of_line = 1 + + while i >= 0 + + let [token, curr_vcol, curr_col] = indtokens[i] + call s:Log(' Analyzing the following token: ' . string(indtokens[i])) + + if len(stack) > 256 " TODO: magic number + return s:IndentError('Stack too long', token, stack) + endif + + if token ==# '<end_of_clause>' + let [ret, res] = s:BeginningOfClauseFound(stack, token, stored_vcol, + \lnum, i) + if ret | return res | endif + + if stored_vcol ==# -1 + call s:Log(' End of clause directly precedes LTI -> return') + return 0 + else + call s:Log(' End of clause (but not end of line) -> return') + return stored_vcol + endif + + elseif stack == ['prev_term_plus'] + if token =~# '[a-zA-Z_@#]' || + \ token ==# '<string>' || token ==# '<string_start>' || + \ token ==# '<quoted_atom>' || token ==# '<quoted_atom_start>' + call s:Log(' previous token found: curr_vcol + plus = ' . + \curr_vcol . " + " . plus) + return curr_vcol + plus + endif + + elseif token ==# 'begin' + let [ret, res] = s:BeginElementFound(stack, token, curr_vcol, + \stored_vcol, 'end', shiftwidth()) + if ret | return res | endif + + " case EXPR of BRANCHES end + " if BRANCHES end + " try EXPR catch BRANCHES end + " try EXPR after BODY end + " try EXPR catch BRANCHES after BODY end + " try EXPR of BRANCHES catch BRANCHES end + " try EXPR of BRANCHES after BODY end + " try EXPR of BRANCHES catch BRANCHES after BODY end + " receive BRANCHES end + " receive BRANCHES after BRANCHES end + " maybe EXPR end + " maybe EXPR else BRANCHES end + + " This branch is not Emacs-compatible + elseif (index(['of', 'receive', 'after', 'if', 'else'], token) != -1 || + \ (token ==# 'catch' && !s:IsCatchStandalone(lnum, i))) && + \ !last_token_of_line && + \ (empty(stack) || stack ==# ['when'] || stack ==# ['->'] || + \ stack ==# ['->', ';']) + + " If we are after of/receive/etc, but these are not the last + " tokens of the line, we want to indent like this: + " + " % stack == [] + " receive stored_vcol, + " LTI + " + " % stack == ['->', ';'] + " receive stored_vcol -> + " B; + " LTI + " + " % stack == ['->'] + " receive stored_vcol -> + " LTI + " + " % stack == ['when'] + " receive stored_vcol when + " LTI + + " stack = [] => LTI is a condition + " stack = ['->'] => LTI is a branch + " stack = ['->', ';'] => LTI is a condition + " stack = ['when'] => LTI is a guard + if empty(stack) || stack == ['->', ';'] + call s:Log(' LTI is in a condition after ' . + \'"of/receive/after/if/else/catch" -> return') + return stored_vcol + elseif stack == ['->'] + call s:Log(' LTI is in a branch after ' . + \'"of/receive/after/if/else/catch" -> return') + return stored_vcol + shiftwidth() + elseif stack == ['when'] + call s:Log(' LTI is in a guard after ' . + \'"of/receive/after/if/else/catch" -> return') + return stored_vcol + shiftwidth() + else + return s:UnexpectedToken(token, stack) + endif + + elseif index(['case', 'if', 'try', 'receive', 'maybe'], token) != -1 + + " stack = [] => LTI is a condition + " stack = ['->'] => LTI is a branch + " stack = ['->', ';'] => LTI is a condition + " stack = ['when'] => LTI is in a guard + if empty(stack) + " pass + elseif (token ==# 'case' && stack[0] ==# 'of') || + \ (token ==# 'if') || + \ (token ==# 'maybe' && stack[0] ==# 'else') || + \ (token ==# 'try' && (stack[0] ==# 'of' || + \ stack[0] ==# 'catch' || + \ stack[0] ==# 'after')) || + \ (token ==# 'receive') + + " From the indentation point of view, the keyword + " (of/catch/after/else/end) before the LTI is what counts, so + " when we reached these tokens, and the stack already had + " a catch/after/else/end, we didn't modify it. + " + " This way when we reach case/try/receive/maybe (i.e. now), + " there is at most one of/catch/after/else/end token in the + " stack. + if token ==# 'case' || token ==# 'try' || + \ (token ==# 'receive' && stack[0] ==# 'after') || + \ (token ==# 'maybe' && stack[0] ==# 'else') + call s:Pop(stack) + endif + + if empty(stack) + call s:Log(' LTI is in a condition; matching ' . + \'"case/if/try/receive/maybe" found') + let stored_vcol = curr_vcol + shiftwidth() + elseif stack[0] ==# 'align_to_begin_element' + call s:Pop(stack) + let stored_vcol = curr_vcol + elseif len(stack) > 1 && stack[0] ==# '->' && stack[1] ==# ';' + call s:Log(' LTI is in a condition; matching ' . + \'"case/if/try/receive/maybe" found') + call s:Pop(stack) + call s:Pop(stack) + let stored_vcol = curr_vcol + shiftwidth() + elseif stack[0] ==# '->' + call s:Log(' LTI is in a branch; matching ' . + \'"case/if/try/receive/maybe" found') + call s:Pop(stack) + let stored_vcol = curr_vcol + 2 * shiftwidth() + elseif stack[0] ==# 'when' + call s:Log(' LTI is in a guard; matching ' . + \'"case/if/try/receive/maybe" found') + call s:Pop(stack) + let stored_vcol = curr_vcol + 2 * shiftwidth() + 2 + endif + + endif + + let [ret, res] = s:BeginElementFound(stack, token, curr_vcol, + \stored_vcol, 'end', shiftwidth()) + if ret | return res | endif + + elseif token ==# 'fun' + let [next_indtoken, next_lnum, next_i] = s:NextIndToken(lnum, i) + call s:Log(' Next indtoken = ' . string(next_indtoken)) + + if !empty(next_indtoken) && next_indtoken[0] =~# '^[A-Z_@]' + " The "fun" is followed by a variable, so we might have a named fun: + " "fun Fun() -> ok end". Thus we take the next token to decide + " whether this is a function definition ("fun()") or just a function + " reference ("fun Mod:Fun"). + let [next_indtoken, _, _] = s:NextIndToken(next_lnum, next_i) + call s:Log(' Next indtoken = ' . string(next_indtoken)) + endif + + if !empty(next_indtoken) && next_indtoken[0] ==# '(' + " We have an anonymous function definition + " (e.g. "fun () -> ok end") + + " stack = [] => LTI is a condition + " stack = ['->'] => LTI is a branch + " stack = ['->', ';'] => LTI is a condition + " stack = ['when'] => LTI is in a guard + if empty(stack) + call s:Log(' LTI is in a condition; matching "fun" found') + let stored_vcol = curr_vcol + shiftwidth() + elseif len(stack) > 1 && stack[0] ==# '->' && stack[1] ==# ';' + call s:Log(' LTI is in a condition; matching "fun" found') + call s:Pop(stack) + call s:Pop(stack) + elseif stack[0] ==# '->' + call s:Log(' LTI is in a branch; matching "fun" found') + call s:Pop(stack) + let stored_vcol = curr_vcol + 2 * shiftwidth() + elseif stack[0] ==# 'when' + call s:Log(' LTI is in a guard; matching "fun" found') + call s:Pop(stack) + let stored_vcol = curr_vcol + 2 * shiftwidth() + 2 + endif + + let [ret, res] = s:BeginElementFound(stack, token, curr_vcol, + \stored_vcol, 'end', shiftwidth()) + if ret | return res | endif + else + " Pass: we have a function reference (e.g. "fun f/0") + endif + + elseif token ==# '[' + " Emacs compatibility + let [ret, res] = s:BeginElementFound(stack, token, curr_vcol, + \stored_vcol, ']', 1) + if ret | return res | endif + + elseif token ==# '<<' + " Emacs compatibility + let [ret, res] = s:BeginElementFound(stack, token, curr_vcol, + \stored_vcol, '>>', 2) + if ret | return res | endif + + elseif token ==# '(' || token ==# '{' + + let end_token = (token ==# '(' ? ')' : + \token ==# '{' ? '}' : 'error') + + if empty(stack) + " We found the opening paren whose block contains the LTI. + let mode = 'inside' + elseif stack[0] ==# end_token + call s:Log(' "' . token . '" pops "' . end_token . '"') + call s:Pop(stack) + + if !empty(stack) && stack[0] ==# 'align_to_begin_element' + " We found the opening paren whose closing paren + " starts LTI + let mode = 'align_to_begin_element' + else + " We found the opening pair for a closing paren that + " was already in the stack. + let mode = 'outside' + endif + else + return s:UnexpectedToken(token, stack) + endif + + if mode ==# 'inside' || mode ==# 'align_to_begin_element' + + if last_token_of_line && i != 0 + " Examples: {{{ + " + " mode == 'inside': + " + " my_func( + " LTI + " + " [Variable, { + " LTI + " + " mode == 'align_to_begin_element': + " + " my_func( + " Params + " ) % LTI + " + " [Variable, { + " Terms + " } % LTI + " }}} + let stack = ['prev_term_plus'] + let plus = (mode ==# 'inside' ? 2 : 1) + call s:Log(' "' . token . + \'" token found at end of line -> find previous token') + elseif mode ==# 'align_to_begin_element' + " Examples: {{{ + " + " mode == 'align_to_begin_element' && !last_token_of_line + " + " my_func(stored_vcol + " ) % LTI + " + " [Variable, {stored_vcol + " } % LTI + " + " mode == 'align_to_begin_element' && i == 0 + " + " ( + " stored_vcol + " ) % LTI + " + " { + " stored_vcol + " } % LTI + " }}} + call s:Log(' "' . token . '" token (whose closing token ' . + \'starts LTI) found -> return') + return curr_vcol + elseif stored_vcol ==# -1 + " Examples: {{{ + " + " mode == 'inside' && stored_vcol == -1 && !last_token_of_line + " + " my_func( + " LTI + " [Variable, { + " LTI + " + " mode == 'inside' && stored_vcol == -1 && i == 0 + " + " ( + " LTI + " + " { + " LTI + " }}} + call s:Log(' "' . token . + \'" token (which directly precedes LTI) found -> return') + return curr_vcol + 1 + else + " Examples: {{{ + " + " mode == 'inside' && stored_vcol != -1 && !last_token_of_line + " + " my_func(stored_vcol, + " LTI + " + " [Variable, {stored_vcol, + " LTI + " + " mode == 'inside' && stored_vcol != -1 && i == 0 + " + " (stored_vcol, + " LTI + " + " {stored_vcol, + " LTI + " }}} + call s:Log(' "' . token . + \'" token (whose block contains LTI) found -> return') + return stored_vcol + endif + endif + + elseif index(['end', ')', ']', '}', '>>'], token) != -1 + + " If we can be sure that there is synchronization in the Erlang + " syntax, we use searchpair to make the script quicker. Otherwise we + " just push the token onto the stack and keep parsing. + + " No synchronization -> no searchpair optimization + if !exists('b:erlang_syntax_synced') + call s:Push(stack, token) + + " We don't have searchpair optimization for '>>' + elseif token ==# '>>' + call s:Push(stack, token) + + elseif token ==# 'end' + let [lnum_new, col_new] = s:SearchEndPair(lnum, curr_col) + + if lnum_new ==# 0 + return s:IndentError('Matching token for "end" not found', + \token, stack) + else + if lnum_new != lnum + call s:Log(' Tokenize for "end" <<<<') + let [lnum, indtokens] = s:TokenizeLine(lnum_new, 'up') + call s:Log(' >>>> Tokenize for "end"') + endif + + let [success, i] = s:GetIndtokenAtCol(indtokens, col_new) + if !success | return i | endif + let [token, curr_vcol, curr_col] = indtokens[i] + call s:Log(' Match for "end" in line ' . lnum_new . ': ' . + \string(indtokens[i])) + endif + + else " token is one of the following: ')', ']', '}' + + call s:Push(stack, token) + + " We have to escape '[', because this string will be interpreted as a + " regexp + let open_paren = (token ==# ')' ? '(' : + \token ==# ']' ? '\[' : + \ '{') + + let [lnum_new, col_new] = s:SearchPair(lnum, curr_col, + \open_paren, '', token) + + if lnum_new ==# 0 + return s:IndentError('Matching token not found', + \token, stack) + else + if lnum_new != lnum + call s:Log(' Tokenize the opening paren <<<<') + let [lnum, indtokens] = s:TokenizeLine(lnum_new, 'up') + call s:Log(' >>>>') + endif + + let [success, i] = s:GetIndtokenAtCol(indtokens, col_new) + if !success | return i | endif + let [token, curr_vcol, curr_col] = indtokens[i] + call s:Log(' Match in line ' . lnum_new . ': ' . + \string(indtokens[i])) + + " Go back to the beginning of the loop and handle the opening paren + continue + endif + endif + + elseif token ==# ';' + + if empty(stack) + call s:Push(stack, ';') + elseif index([';', '->', 'when', 'end', 'after', 'catch', 'else'], + \stack[0]) != -1 + " Pass: + " + " - If the stack top is another ';', then one ';' is + " enough. + " - If the stack top is an '->' or a 'when', then we + " should keep that, because they signify the type of the + " LTI (branch, condition or guard). + " - From the indentation point of view, the keyword + " (of/catch/after/else/end) before the LTI is what counts, so + " if the stack already has a catch/after/else/end, we don't + " modify it. This way when we reach case/try/receive/maybe, + " there will be at most one of/catch/after/else/end token in + " the stack. + else + return s:UnexpectedToken(token, stack) + endif + + elseif token ==# '->' + + if empty(stack) && !last_token_of_line + call s:Log(' LTI is in expression after arrow -> return') + return stored_vcol + elseif empty(stack) || stack[0] ==# ';' || stack[0] ==# 'end' + " stack = [';'] -> LTI is either a branch or in a guard + " stack = ['->'] -> LTI is a condition + " stack = ['->', ';'] -> LTI is a branch + call s:Push(stack, '->') + elseif index(['->', 'when', 'end', 'after', 'catch', 'else'], + \stack[0]) != -1 + " Pass: + " + " - If the stack top is another '->', then one '->' is + " enough. + " - If the stack top is a 'when', then we should keep + " that, because this signifies that LTI is a in a guard. + " - From the indentation point of view, the keyword + " (of/catch/after/else/end) before the LTI is what counts, so + " if the stack already has a catch/after/else/end, we don't + " modify it. This way when we reach case/try/receive/maybe, + " there will be at most one of/catch/after/else/end token in + " the stack. + else + return s:UnexpectedToken(token, stack) + endif + + elseif token ==# 'when' + + " Pop all ';' from the top of the stack + while !empty(stack) && stack[0] ==# ';' + call s:Pop(stack) + endwhile + + if empty(stack) + if semicolon_abscol != '' + let stored_vcol = semicolon_abscol + endif + if !last_token_of_line + " Example: + " when A, + " LTI + let [ret, res] = s:BeginElementFoundIfEmpty(stack, token, curr_vcol, + \stored_vcol, shiftwidth()) + if ret | return res | endif + else + " Example: + " when + " LTI + call s:Push(stack, token) + endif + elseif index(['->', 'when', 'end', 'after', 'catch', 'else'], + \stack[0]) != -1 + " Pass: + " - If the stack top is another 'when', then one 'when' is + " enough. + " - If the stack top is an '->' or a 'when', then we + " should keep that, because they signify the type of the + " LTI (branch, condition or guard). + " - From the indentation point of view, the keyword + " (of/catch/after/else/end) before the LTI is what counts, so + " if the stack already has a catch/after/else/end, we don't + " modify it. This way when we reach case/try/receive/maybe, + " there will be at most one of/catch/after/else/end token in + " the stack. + else + return s:UnexpectedToken(token, stack) + endif + + elseif token ==# 'of' || token ==# 'after' || token ==# 'else' || + \ (token ==# 'catch' && !s:IsCatchStandalone(lnum, i)) + + if token ==# 'after' || token ==# 'else' + " If LTI is between an after/else and the corresponding 'end', then + " let's return because calculating the indentation based on + " after/else is enough. + " + " Example: + " receive A after + " LTI + " maybe A else + " LTI + " + " Note about Emacs compabitility {{{ + " + " It would be fine to indent the examples above the following way: + " + " receive A after + " LTI + " maybe A else + " LTI + " + " We intend it the way above because that is how Emacs does it. + " Also, this is a bit faster. + " + " We are still not 100% Emacs compatible because of placing the + " 'end' after the indented blocks. + " + " Emacs example: + " + " receive A after + " LTI + " end, + " maybe A else + " LTI + " end % Yes, it's here (in OTP 25.0, might change + " % later) + " + " vim-erlang example: + " + " receive A after + " LTI + " end, + " maybe A else + " LTI + " end + " }}} + let [ret, res] = s:BeginElementFoundIfEmpty(stack, token, curr_vcol, + \stored_vcol, shiftwidth()) + if ret | return res | endif + endif + + if empty(stack) || stack[0] ==# '->' || stack[0] ==# 'when' + call s:Push(stack, token) + elseif stack[0] ==# 'catch' || stack[0] ==# 'after' || + \stack[0] ==# 'else' || stack[0] ==# 'end' + " Pass: From the indentation point of view, the keyword + " (of/catch/after/end) before the LTI is what counts, so + " if the stack already has a catch/after/end, we don't + " modify it. This way when we reach case/try/receive, + " there will be at most one of/catch/after/end token in + " the stack. + else + return s:UnexpectedToken(token, stack) + endif + + elseif token ==# '||' && empty(stack) && !last_token_of_line + + call s:Log(' LTI is in expression after "||" -> return') + return stored_vcol + + else + call s:Log(' Misc token, stack unchanged = ' . string(stack)) + + endif + + if empty(stack) || stack[0] ==# '->' || stack[0] ==# 'when' + let stored_vcol = curr_vcol + let semicolon_abscol = '' + call s:Log(' Misc token when the stack is empty or has "->" ' . + \'-> setting stored_vcol to ' . stored_vcol) + elseif stack[0] ==# ';' + let semicolon_abscol = curr_vcol + call s:Log(' Setting semicolon-stored_vcol to ' . stored_vcol) + endif + + let i -= 1 + call s:Log(' Token processed. stored_vcol=' . stored_vcol) + + let last_token_of_line = 0 + + endwhile " iteration on tokens in a line + + call s:Log(' Line analyzed. stored_vcol=' . stored_vcol) + + if empty(stack) && stored_vcol != -1 && + \ (!empty(indtokens) && indtokens[0][0] != '<string_end>' && + \ indtokens[0][0] != '<quoted_atom_end>') + call s:Log(' Empty stack at the beginning of the line -> return') + return stored_vcol + endif + + let lnum -= 1 + + endwhile " iteration on lines + +endfunction + +" ErlangIndent function {{{1 +" ===================== + +function! ErlangIndent() + + call s:ClearTokenCacheIfNeeded() + + let currline = getline(v:lnum) + call s:Log('Indenting line ' . v:lnum . ': ' . currline) + + if s:IsLineStringContinuation(v:lnum) || s:IsLineAtomContinuation(v:lnum) + call s:Log('String or atom continuation found -> ' . + \'leaving indentation unchanged') + return -1 + endif + + " If the line starts with the comment, and so is the previous non-blank line + if currline =~# '^\s*%' + let lnum = prevnonblank(v:lnum - 1) + if lnum ==# 0 + call s:Log('First non-empty line of the file -> return 0.') + return 0 + else + let ml = matchlist(getline(lnum), '^\(\s*\)%') + " If the previous line also starts with a comment, then return the same + " indentation that line has. Otherwise exit from this special "if" and + " don't care that the current line is a comment. + if !empty(ml) + let new_col = s:CalcVCol(ml[1], 0, len(ml[1]) - 1, 0, &tabstop) + call s:Log('Comment line after another comment line -> ' . + \'use same indent: ' . new_col) + return new_col + endif + endif + endif + + let ml = matchlist(currline, + \'^\(\s*\)\(\%(end\|of\|catch\|after\|else\)\>\|[)\]}]\|>>\)') + + " If the line has a special beginning, but not a standalone catch + if !empty(ml) && !(ml[2] ==# 'catch' && s:IsCatchStandalone(v:lnum, 0)) + + let curr_col = len(ml[1]) + + " If we can be sure that there is synchronization in the Erlang + " syntax, we use searchpair to make the script quicker. + if ml[2] ==# 'end' && exists('b:erlang_syntax_synced') + + let [lnum, col] = s:SearchEndPair(v:lnum, curr_col) + + if lnum ==# 0 + return s:IndentError('Matching token for "end" not found', + \'end', []) + else + call s:Log(' Tokenize for "end" <<<<') + let [lnum, indtokens] = s:TokenizeLine(lnum, 'up') + call s:Log(' >>>> Tokenize for "end"') + + let [success, i] = s:GetIndtokenAtCol(indtokens, col) + if !success | return i | endif + let [token, curr_vcol, curr_col] = indtokens[i] + call s:Log(' Match for "end" in line ' . lnum . ': ' . + \string(indtokens[i])) + return curr_vcol + endif + + else + + call s:Log(" Line type = 'end'") + let new_col = s:ErlangCalcIndent(v:lnum - 1, + \[ml[2], 'align_to_begin_element']) + endif + else + call s:Log(" Line type = 'normal'") + + let new_col = s:ErlangCalcIndent(v:lnum - 1, []) + if currline =~# '^\s*when\>' + let new_col += 2 + endif + endif + + if new_col < -1 + call s:Log('WARNING: returning new_col == ' . new_col) + return g:erlang_unexpected_token_indent + endif + + return new_col + +endfunction + +" ErlangShowTokensInLine functions {{{1 +" ================================ + +" These functions are useful during development. + +function! ErlangShowTokensInLine(line) + echo "Line: " . a:line + let indtokens = s:GetTokensFromLine(a:line, 0, 0, &tabstop) + echo "Tokens:" + for it in indtokens + echo it + endfor +endfunction + +function! ErlangShowTokensInCurrentLine() + return ErlangShowTokensInLine(getline('.')) +endfunction + +" Cleanup {{{1 +" ======= + +let &cpo = s:cpo_save +unlet s:cpo_save + +" vim: sw=2 et fdm=marker |