vis
a vi-like editor based on Plan 9's structural regular expressions
git clone https://9o.is/git/vis.git
bash.lua
(5762B)
1 -- Copyright 2006-2025 Mitchell. See LICENSE.
2 -- Shell LPeg lexer.
3
4 local lexer = lexer
5 local P, S, B = lpeg.P, lpeg.S, lpeg.B
6
7 local lex = lexer.new(...)
8
9 -- Keywords.
10 lex:add_rule('keyword', lex:tag(lexer.KEYWORD, lex:word_match(lexer.KEYWORD)))
11
12 -- Builtins.
13 lex:add_rule('builtin',
14 lex:tag(lexer.FUNCTION_BUILTIN, lex:word_match(lexer.FUNCTION_BUILTIN)) * -P('='))
15
16 -- Variable assignment.
17 local assign = lex:tag(lexer.VARIABLE, lexer.word) * lex:tag(lexer.OPERATOR, '=')
18 lex:add_rule('assign', lexer.starts_line(assign, true))
19
20 -- Identifiers.
21 lex:add_rule('identifier', lex:tag(lexer.IDENTIFIER, lexer.word))
22
23 -- Strings.
24 local sq_str = -B('\\') * lexer.range("'", false, false)
25 local dq_str = -B('\\') * lexer.range('"')
26 local heredoc = '<<' * P(function(input, index)
27 local _, e, minus, _, delimiter = input:find('^(%-?)%s*(["\']?)([%w_]+)%2[^\n]*[\n\r\f;]+', index)
28 if not delimiter then return nil end
29 -- If the starting delimiter of a here-doc begins with "-", then spaces are allowed to come
30 -- before the closing delimiter.
31 _, e =
32 input:find((minus == '' and '[\n\r\f]+' or '[\n\r\f]+[ \t]*') .. delimiter .. '%f[^%w_]', e)
33 return e and e + 1 or #input + 1
34 end)
35 local ex_str = -B('\\') * '`'
36 lex:add_rule('string',
37 lex:tag(lexer.STRING, sq_str + dq_str + heredoc) + lex:tag(lexer.EMBEDDED, ex_str))
38
39 -- Comments.
40 lex:add_rule('comment', lex:tag(lexer.COMMENT, -B('\\') * lexer.to_eol('#')))
41
42 -- Numbers.
43 lex:add_rule('number', lex:tag(lexer.NUMBER, lexer.number))
44
45 -- Variables.
46 local builtin_var = lex:tag(lexer.OPERATOR, '$' * P('{')^-1) * lex:tag(lexer.VARIABLE_BUILTIN,
47 lex:word_match(lexer.VARIABLE_BUILTIN) + S('!#?*@$-') * -lexer.alnum + lexer.digit^1)
48 local var_ref = lex:tag(lexer.OPERATOR, '$' * ('{' * S('!#')^-1)^-1) *
49 lex:tag(lexer.VARIABLE, lexer.word)
50 local patt_expansion = lex:tag(lexer.DEFAULT, '/#' + '#' * P('#')^-1)
51 lex:add_rule('variable', builtin_var + var_ref * patt_expansion^-1)
52
53 -- Operators.
54 local op = S('!<>&|;$()[]{}') + lpeg.B(lexer.space) * S('.:') * #lexer.space
55
56 local function in_expr(constructs)
57 return P(function(input, index)
58 local line = input:sub(1, index):match('[^\r\n]*$')
59 for k, v in pairs(constructs) do
60 local s = line:find(k, 1, true)
61 if not s then goto continue end
62 local e = line:find(v, 1, true)
63 if not e or e < s then return true end
64 ::continue::
65 end
66 return nil
67 end)
68 end
69
70 local file_op = '-' * (S('abcdefghkprstuwxGLNOS') + 'ef' + 'nt' + 'ot')
71 local shell_op = '-o'
72 local var_op = '-' * S('vR')
73 local string_op = '-' * S('zn') + S('!=')^-1 * '=' + S('<>')
74 local num_op = '-' * lexer.word_match('eq ne lt le gt ge')
75 local in_cond_expr = in_expr{['[[ '] = ' ]]', ['[ '] = ' ]'}
76 local conditional_op = (num_op + file_op + shell_op + var_op + string_op) * #lexer.space *
77 in_cond_expr
78
79 local in_arith_expr = in_expr{['(('] = '))'}
80 local arith_op = (S('+!~*/%<>=&^|?:,') + '--' + '-' * #S(' \t')) * in_arith_expr
81
82 -- TODO: performance is terrible on large files.
83 -- lex:add_rule('operator', lex:tag(lexer.OPERATOR, op + conditional_op + arith_op))
84 lex:add_rule('operator', lex:tag(lexer.OPERATOR, op))
85
86 -- Flags/options.
87 lex:add_rule('flag', lex:tag(lexer.DEFAULT, '-' * P('-')^-1 * lexer.word * ('-' * lexer.word)^0))
88
89 -- Fold points.
90 lex:add_fold_point(lexer.KEYWORD, 'if', 'fi')
91 lex:add_fold_point(lexer.KEYWORD, 'case', 'esac')
92 lex:add_fold_point(lexer.KEYWORD, 'do', 'done')
93 lex:add_fold_point(lexer.OPERATOR, '{', '}')
94
95 -- Word lists.
96 lex:set_word_list(lexer.KEYWORD, {
97 'if', 'then', 'elif', 'else', 'fi', 'time', 'for', 'in', 'until', 'while', 'do', 'done', 'case',
98 'esac', 'coproc', 'select', 'function'
99 })
100
101 lex:set_word_list(lexer.FUNCTION_BUILTIN, {
102 -- Shell built-ins.
103 'break', 'cd', 'continue', 'eval', 'exec', 'exit', 'export', 'getopts', 'hash', 'pwd', 'readonly',
104 'return', 'shift', 'test', 'times', 'trap', 'umask', 'unset',
105 -- Bash built-ins.
106 'alias', 'bind', 'builtin', 'caller', 'command', 'declare', 'echo', 'enable', 'help', 'let',
107 'local', 'logout', 'mapfile', 'printf', 'read', 'readarray', 'source', 'type', 'typeset',
108 'ulimit', 'unalias', --
109 'set', 'shopt', -- shell behavior
110 'dirs', 'popd', 'pushd', -- directory stack
111 'bg', 'fg', 'jobs', 'kill', 'wait', 'disown', 'suspend', -- job control
112 'fc', 'history' -- history
113 })
114
115 lex:set_word_list(lexer.VARIABLE_BUILTIN, {
116 -- Shell built-ins.
117 'CDPATH', 'HOME', 'IFS', 'MAIL', 'MAILPATH', 'OPTARG', 'OPTIND', 'PATH', 'PS1', 'PS2',
118 -- Bash built-ins.
119 'BASH', 'BASHOPTS', 'BASHPID', 'BASH_ALIASES', 'BASH_ARGC', 'BASH_ARGV', 'BASH_ARGV0',
120 'BASH_CMDS', 'BASH_COMMAND', 'BASH_COMPAT', 'BASH_ENV', 'BASH_EXECUTION_STRING', 'BASH_LINENO',
121 'BASH_LOADABLES_PATH', 'BASH_REMATCH', 'BASH_SOURCE', 'BASH_SUBSHELL', 'BASH_VERSINFO',
122 'BASH_VERSION', 'BASH_XTRACEFD', 'CHILD_MAX', 'COLUMNS', 'COMP_CWORD', 'COMP_LINE', 'COMP_POINT',
123 'COMP_TYPE', 'COMP_KEY', 'COMP_WORDBREAKS', 'COMP_WORDS', 'COMP_REPLY', 'COPROC', 'DIRSTACK',
124 'EMACS', 'ENV', 'EPOCHREALTIME', 'EPOCHSECONDS', 'EUID', 'EXECIGNORE', 'FCEDIT', 'FIGNORE',
125 'FUNCNAME', 'FUNCNEST', 'GLOBIGNORE', 'GROUPS', 'histchars', 'HISTCMD', 'HISTCONTROL', 'HISTFILE',
126 'HISTFILESIZE', 'HISTIGNORE', 'HISTSIZE', 'HISTTIMEFORMAT', 'HOSTFILE', 'HOSTNAME', 'HOSTTYPE',
127 'IGNOREEOF', 'INPUTRC', 'INSIDE_EMACS', 'LANG', 'LC_ALL', 'LC_COLLATE', 'LC_CTYPE', 'LC_MESSAGES',
128 'LC_NUMERIC', 'LC_TIME', 'LINENO', 'LINES', 'MACHTYPE', 'MAILCHECK', 'MAPFILE', 'OLDPWD',
129 'OPTERR', 'OSTYPE', 'PIPESTATUS', 'POSIXLY_CORRECT', 'PPID', 'PROMPT_COMMAND', 'PROMPT_DIRTRIM',
130 'PSO', 'PS3', 'PS4', 'PWD', 'RANDOM', 'READLINE_LINE', 'READLINE_MARK', 'READLINE_POINT', 'REPLY',
131 'SECONDS', 'SHELL', 'SHELLOPTS', 'SHLVL', 'SRANDOM', 'TIMEFORMAT', 'TMOUT', 'TMPDIR', 'UID',
132 -- Job control.
133 'auto_resume'
134 })
135
136 lexer.property['scintillua.comment'] = '#'
137
138 return lex