add a VimL lexer (closes #34)

lib/rouge.rb

@@ -32,6 +32,7 @@ def highlight(text, lexer, formatter)
 
 load load_dir.join('rouge/lexers/make.rb')
 load load_dir.join('rouge/lexers/shell.rb')
+load load_dir.join('rouge/lexers/viml.rb')
 
 load load_dir.join('rouge/lexers/javascript.rb')
 load load_dir.join('rouge/lexers/css.rb')

lib/rouge/lexers/viml.rb

@@ -0,0 +1,93 @@
+module Rouge
+  module Lexers
+    class VimL < RegexLexer
+      tag 'viml'
+      aliases 'vim', 'vimscript', 'ex'
+      filenames '*.vim', '*.vba', '.vimrc', '.exrc', '.gvimrc',
+                '_vimrc', '_exrc', '_gvimrc' # _ names for windows
+
+      mimetypes 'text/x-vim'
+
+      state :root do
+        rule /^(\s*)(".*?)$/ do
+          group 'Text'; group 'Comment'
+        end
+
+        rule /^\s*\\/, 'Literal.String.Escape'
+
+        rule /[ \t]+/, 'Text'
+
+        # TODO: regexes can have other delimiters
+        rule %r(/(\\\\|\\/|[^\n/])*/), 'Literal.String.Regex'
+        rule %r("(\\\\|\\"|[^\n"])*"), 'Literal.String.Double'
+        rule %r('(\\\\|\\'|[^\n'])*'), 'Literal.String.Single'
+
+        # if it's not a string, it's a comment.
+        rule /(?<=\s)"[^-:.%#=*].*?$/, 'Comment'
+
+        rule /-?\d+/, 'Literal.Number'
+        rule /#[0-9a-f]{6}/i, 'Literal.Number.Hex'
+        rule /^:/, 'Punctuation'
+        rule /[():<>+=!\[\]{}\|,~.-]/, 'Punctuation'
+        rule /\b(let|if|else|endif|elseif|fun|function|endfunction)\b/,
+          'Keyword'
+
+        rule /\b(NONE|bold|italic|underline|dark|light)\b/, 'Name.Builtin'
+
+        rule /[absg]:\w+\b/, 'Name.Variable'
+        rule /\b\w+\b/, 'Postprocess.Name'
+
+        # no errors in VimL!
+        rule /./m, 'Text'
+      end
+
+      postprocess 'Postprocess.Name' do |tok, name|
+        require Pathname.new(__FILE__).dirname.join('viml/keywords')
+        keywords = self.class.keywords
+
+        if mapping_contains?(keywords[:command], name)
+          token 'Keyword', name
+        elsif mapping_contains?(keywords[:option], name)
+          token 'Name.Builtin', name
+        elsif mapping_contains?(keywords[:auto], name)
+          token 'Name.Builtin', name
+        else
+          token 'Text', name
+        end
+      end
+
+      def mapping_contains?(mapping, word)
+        shortest, longest = find_likely_mapping(mapping, word)
+
+        word.start_with?(shortest) and longest.start_with?(word)
+      end
+
+      # binary search through the mappings to find the one that's likely
+      # to actually work.
+      def find_likely_mapping(mapping, word)
+        min = 0
+        max = mapping.size
+
+        until max == min
+          mid = (max + min) / 2
+
+          cmp, _ = mapping[mid]
+
+          case word <=> cmp
+          when 1
+            # too low
+            min = mid + 1
+          when -1
+            # too high
+            max = mid
+          when 0
+            # just right, abort!
+            return mapping[mid]
+          end
+        end
+
+        mapping[max - 1]
+      end
+    end
+  end
+end

lib/rouge/lexers/viml/keywords.rb

@@ -0,0 +1,11 @@
+# DO NOT EDIT: automatically generated by `rake vimkeywords`.
+# see tasks/vim.rake for more info.
+module Rouge
+  module Lexers
+    class VimL
+      def self.keywords
+        @keywords ||= {:command=>[[":p", ":p"], ["Allargs", "Allargs"], ["DiffOrig", "DiffOrig"], ["Error", "Error"], ["Man", "Man"], ["MyCommand", "MyCommand"], ["Mycmd", "Mycmd"], ["N", "N"], ["N", "Next"], ["P", "P"], ["P", "Print"], ["Ren", "Ren"], ["Rena", "Rena"], ["Renu", "Renu"], ["TOhtml", "TOhtml"], ["X", "X"], ["XMLent", "XMLent"], ["XMLns", "XMLns"], ["a", "a"], ["ab", "ab"], ["abc", "abclear"], ["abo", "aboveleft"], ["al", "all"], ["ar", "ar"], ["ar", "args"], ["arga", "argadd"], ["argd", "argdelete"], ["argdo", "argdo"], ["arge", "argedit"], ["argg", "argglobal"], ["argl", "arglocal"], ["argu", "argument"], ["as", "ascii"], ["au", "au"], ["b", "buffer"], ["bN", "bNext"], ["ba", "ball"], ["bad", "badd"], ["bar", "bar"], ["bd", "bdelete"], ["bel", "belowright"], ["bf", "bfirst"], ["bl", "blast"], ["bm", "bmodified"], ["bn", "bnext"], ["bo", "botright"], ["bp", "bprevious"], ["br", "br"], ["br", "brewind"], ["brea", "break"], ["breaka", "breakadd"], ["breakd", "breakdel"], ["breakl", "breaklist"], ["bro", "browse"], ["browseset", "browseset"], ["bu", "bu"], ["buf", "buf"], ["bufdo", "bufdo"], ["buffers", "buffers"], ["bun", "bunload"], ["bw", "bwipeout"], ["c", "c"], ["c", "change"], ["cN", "cN"], ["cN", "cNext"], ["cNf", "cNf"], ["cNf", "cNfile"], ["cabc", "cabclear"], ["cad", "cad"], ["cad", "caddexpr"], ["caddb", "caddbuffer"], ["caddf", "caddfile"], ["cal", "call"], ["cat", "catch"], ["cb", "cbuffer"], ["cc", "cc"], ["ccl", "cclose"], ["cd", "cd"], ["ce", "center"], ["cex", "cexpr"], ["cf", "cfile"], ["cfir", "cfirst"], ["cg", "cgetfile"], ["cgetb", "cgetbuffer"], ["cgete", "cgetexpr"], ["changes", "changes"], ["chd", "chdir"], ["che", "checkpath"], ["checkt", "checktime"], ["cl", "cl"], ["cl", "clist"], ["cla", "clast"], ["clo", "close"], ["cmapc", "cmapclear"], ["cmdname", "cmdname"], ["cn", "cn"], ["cn", "cnext"], ["cnew", "cnewer"], ["cnf", "cnf"], ["cnf", "cnfile"], ["co", "copy"], ["col", "colder"], ["colo", "colorscheme"], ["com", "com"], ["comc", "comclear"], ["comment", "comment"], ["comp", "compiler"], ["con", "con"], ["con", "continue"], ["conf", "confirm"], ["cope", "copen"], ["count", "count"], ["cp", "cprevious"], ["cpf", "cpfile"], ["cq", "cquit"], ["cr", "crewind"], ["cs", "cs"], ["cscope", "cscope"], ["cstag", "cstag"], ["cuna", "cunabbrev"], ["cw", "cwindow"], ["d", "d"], ["d", "delete"], ["de", "de"], ["debug", "debug"], ["debugg", "debuggreedy"], ["del", "del"], ["delc", "delcommand"], ["delf", "delf"], ["delf", "delfunction"], ["delm", "delmarks"], ["di", "di"], ["di", "display"], ["diffg", "diffget"], ["diffo", "diffo"], ["diffoff", "diffoff"], ["diffp", "diffp"], ["diffpatch", "diffpatch"], ["diffpu", "diffput"], ["diffsplit", "diffsplit"], ["difft", "difft"], ["diffthis", "diffthis"], ["diffu", "diffupdate"], ["dig", "dig"], ["dig", "digraphs"], ["dj", "djump"], ["dl", "dlist"], ["do", "do"], ["doau", "doau"], ["dr", "drop"], ["ds", "dsearch"], ["dsp", "dsplit"], ["dwim", "dwim"], ["e", "e"], ["e", "edit"], ["e:e", "e:e"], ["e:e:e", "e:e:e"], ["e:e:r", "e:e:r"], ["ea", "ea"], ["earlier", "earlier"], ["ec", "ec"], ["echoe", "echoerr"], ["echom", "echomsg"], ["echon", "echon"], ["el", "else"], ["elsei", "elseif"], ["em", "emenu"], ["emenu", "emenu"], ["en", "en"], ["en", "endif"], ["endf", "endf"], ["endf", "endfunction"], ["endfo", "endfor"], ["endfun", "endfun"], ["endt", "endtry"], ["endw", "endwhile"], ["ene", "enew"], ["ex", "ex"], ["exi", "exit"], ["exu", "exusage"], ["f", "f"], ["f", "file"], ["filename", "filename"], ["files", "files"], ["filet", "filet"], ["filetype", "filetype"], ["fin", "fin"], ["fin", "find"], ["fina", "finally"], ["fini", "finish"], ["fir", "first"], ["fix", "fixdel"], ["fo", "fold"], ["foldc", "foldclose"], ["foldd", "folddoopen"], ["folddoc", "folddoclosed"], ["foldo", "foldopen"], ["for", "for"], ["fu", "fu"], ["fu", "function"], ["fun", "fun"], ["g", "g"], ["get", "get"], ["go", "goto"], ["gr", "grep"], ["grepa", "grepadd"], ["gs", "gs"], ["gui", "gui"], ["gvim", "gvim"], ["h", "h"], ["h", "help"], ["ha", "hardcopy"], ["helpf", "helpfind"], ["helpg", "helpgrep"], ["helpt", "helptags"], ["hi", "hi"], ["hid", "hide"], ["his", "history"], ["i", "i"], ["ia", "ia"], ["iabc", "iabclear"], ["if", "if"], ["ij", "ijump"], ["il", "ilist"], ["imapc", "imapclear"], ["in", "in"], ["index", "index"], ["intro", "intro"], ["is", "isearch"], ["isp", "isplit"], ["iuna", "iunabbrev"], ["j", "join"], ["ju", "jumps"], ["k", "k"], ["kee", "keepmarks"], ["keepa", "keepa"], ["keepalt", "keepalt"], ["keepj", "keepjumps"], ["l", "l"], ["l", "list"], ["lN", "lN"], ["lN", "lNext"], ["lNf", "lNf"], ["lNf", "lNfile"], ["la", "la"], ["la", "last"], ["lad", "lad"], ["lad", "laddexpr"], ["laddb", "laddbuffer"], ["laddf", "laddfile"], ["lan", "lan"], ["lan", "language"], ["lat", "lat"], ["later", "later"], ["lb", "lbuffer"], ["lc", "lcd"], ["lch", "lchdir"], ["lcl", "lclose"], ["lcs", "lcs"], ["lcscope", "lcscope"], ["le", "left"], ["lefta", "leftabove"], ["let", "let"], ["lex", "lexpr"], ["lf", "lfile"], ["lfir", "lfirst"], ["lg", "lgetfile"], ["lgetb", "lgetbuffer"], ["lgete", "lgetexpr"], ["lgr", "lgrep"], ["lgrepa", "lgrepadd"], ["lh", "lhelpgrep"], ["ll", "ll"], ["lla", "llast"], ["lli", "llist"], ["lmak", "lmake"], ["lmapc", "lmapclear"], ["lne", "lne"], ["lne", "lnext"], ["lnew", "lnewer"], ["lnf", "lnf"], ["lnf", "lnfile"], ["lo", "lo"], ["lo", "loadview"], ["loadk", "loadk"], ["loadkeymap", "loadkeymap"], ["loc", "lockmarks"], ["locale", "locale"], ["lockv", "lockvar"], ["lol", "lolder"], ["lop", "lopen"], ["lp", "lprevious"], ["lpf", "lpfile"], ["lr", "lrewind"], ["ls", "ls"], ["lt", "ltag"], ["lua", "lua"], ["luado", "luado"], ["luafile", "luafile"], ["lv", "lvimgrep"], ["lvimgrepa", "lvimgrepadd"], ["lw", "lwindow"], ["m", "move"], ["ma", "ma"], ["ma", "mark"], ["main", "main"], ["main", "main"], ["mak", "make"], ["marks", "marks"], ["mat", "match"], ["menut", "menut"], ["menut", "menutranslate"], ["mes", "mes"], ["messages", "messages"], ["mk", "mk"], ["mk", "mkexrc"], ["mkdir", "mkdir"], ["mks", "mksession"], ["mksp", "mkspell"], ["mkv", "mkv"], ["mkv", "mkvimrc"], ["mkvie", "mkview"], ["mo", "mo"], ["mod", "mode"], ["mv", "mv"], ["mz", "mz"], ["mz", "mzscheme"], ["mzf", "mzfile"], ["n", "n"], ["n", "n"], ["n", "next"], ["nb", "nbkey"], ["nbc", "nbclose"], ["nbs", "nbstart"], ["ne", "ne"], ["new", "new"], ["nkf", "nkf"], ["nmapc", "nmapclear"], ["noa", "noa"], ["noautocmd", "noautocmd"], ["noh", "nohlsearch"], ["nu", "number"], ["o", "o"], ["o", "open"], ["ol", "oldfiles"], ["omapc", "omapclear"], ["on", "only"], ["opt", "options"], ["ownsyntax", "ownsyntax"], ["p", "p"], ["p", "print"], ["p:", "p:"], ["p:", "p:"], ["p:gs", "p:gs"], ["p:h", "p:h"], ["p:h:h", "p:h:h"], ["p:r", "p:r"], ["p:t", "p:t"], ["pat", "pat"], ["pat", "pat"], ["pc", "pclose"], ["pe", "pe"], ["pe", "perl"], ["ped", "pedit"], ["perld", "perldo"], ["po", "pop"], ["popu", "popu"], ["popu", "popup"], ["pp", "ppop"], ["pr", "pr"], ["pre", "preserve"], ["prev", "previous"], ["pro", "pro"], ["prof", "profile"], ["profd", "profdel"], ["promptf", "promptfind"], ["promptr", "promptrepl"], ["ps", "psearch"], ["ptN", "ptN"], ["ptN", "ptNext"], ["pta", "ptag"], ["ptf", "ptfirst"], ["ptj", "ptjump"], ["ptl", "ptlast"], ["ptn", "ptn"], ["ptn", "ptnext"], ["ptp", "ptprevious"], ["ptr", "ptrewind"], ["pts", "ptselect"], ["pu", "put"], ["pw", "pwd"], ["py", "py"], ["py", "python"], ["py3", "py3"], ["py3", "py3"], ["py3file", "py3file"], ["pyf", "pyfile"], ["python3", "python3"], ["q", "q"], ["q", "quit"], ["qa", "qall"], ["quita", "quitall"], ["quote", "quote"], ["r", "r"], ["r", "r"], ["r", "read"], ["r:e", "r:e"], ["r:r", "r:r"], ["r:r:r", "r:r:r"], ["re", "re"], ["rec", "recover"], ["red", "red"], ["red", "redo"], ["redi", "redir"], ["redr", "redraw"], ["redraws", "redrawstatus"], ["reg", "registers"], ["res", "resize"], ["ret", "retab"], ["retu", "return"], ["rew", "rewind"], ["ri", "right"], ["rightb", "rightbelow"], ["ru", "ru"], ["ru", "runtime"], ["rub", "ruby"], ["rubyd", "rubydo"], ["rubyf", "rubyfile"], ["rundo", "rundo"], ["rv", "rviminfo"], ["s", "s"], ["s", "s"], ["s", "s"], ["s", "s"], ["sN", "sNext"], ["sa", "sargument"], ["sal", "sall"], ["san", "sandbox"], ["sav", "saveas"], ["sb", "sbuffer"], ["sbN", "sbNext"], ["sba", "sball"], ["sbf", "sbfirst"], ["sbl", "sblast"], ["sbm", "sbmodified"], ["sbn", "sbnext"], ["sbp", "sbprevious"], ["sbr", "sbrewind"], ["scrip", "scrip"], ["scrip", "scriptnames"], ["scripte", "scriptencoding"], ["scs", "scs"], ["scscope", "scscope"], ["se", "set"], ["setf", "setfiletype"], ["setg", "setglobal"], ["setl", "setlocal"], ["sf", "sfind"], ["sfir", "sfirst"], ["sh", "shell"], ["si", "si"], ["sig", "sig"], ["sign", "sign"], ["sil", "silent"], ["sim", "simalt"], ["sl", "sl"], ["sl", "sleep"], ["sla", "slast"], ["sm", "smagic"], ["sm", "smap"], ["sme", "sme"], ["smenu", "smenu"], ["sn", "snext"], ["sni", "sniff"], ["sno", "snomagic"], ["snoreme", "snoreme"], ["snoremenu", "snoremenu"], ["so", "so"], ["so", "source"], ["sor", "sort"], ["sp", "split"], ["spe", "spe"], ["spe", "spellgood"], ["spelld", "spelldump"], ["spelli", "spellinfo"], ["spellr", "spellrepall"], ["spellu", "spellundo"], ["spellw", "spellwrong"], ["spr", "sprevious"], ["sre", "srewind"], ["st", "st"], ["st", "stop"], ["sta", "stag"], ["star", "star"], ["star", "startinsert"], ["start", "start"], ["startg", "startgreplace"], ["startr", "startreplace"], ["stj", "stjump"], ["stopi", "stopinsert"], ["sts", "stselect"], ["sub", "sub"], ["sub", "sub"], ["sun", "sunhide"], ["sunme", "sunme"], ["sunmenu", "sunmenu"], ["sus", "suspend"], ["sv", "sview"], ["sw", "swapname"], ["sy", "sy"], ["syn", "syn"], ["sync", "sync"], ["syncbind", "syncbind"], ["synlist", "synlist"], ["t", "t"], ["t:r", "t:r"], ["tN", "tN"], ["tN", "tNext"], ["ta", "ta"], ["ta", "tag"], ["tab", "tab"], ["tabN", "tabN"], ["tabN", "tabNext"], ["tabc", "tabclose"], ["tabd", "tabdo"], ["tabe", "tabedit"], ["tabf", "tabfind"], ["tabfir", "tabfirst"], ["tabl", "tablast"], ["tabm", "tabmove"], ["tabn", "tabnext"], ["tabnew", "tabnew"], ["tabo", "tabonly"], ["tabp", "tabprevious"], ["tabr", "tabrewind"], ["tabs", "tabs"], ["tags", "tags"], ["tc", "tcl"], ["tcld", "tcldo"], ["tclf", "tclfile"], ["te", "tearoff"], ["tf", "tfirst"], ["th", "throw"], ["tj", "tjump"], ["tl", "tlast"], ["tm", "tm"], ["tm", "tmenu"], ["tn", "tn"], ["tn", "tnext"], ["to", "topleft"], ["tp", "tprevious"], ["tr", "tr"], ["tr", "trewind"], ["try", "try"], ["ts", "tselect"], ["tu", "tu"], ["tu", "tunmenu"], ["u", "u"], ["u", "undo"], ["un", "un"], ["una", "unabbreviate"], ["undoj", "undojoin"], ["undol", "undolist"], ["unh", "unhide"], ["unl", "unl"], ["unlo", "unlockvar"], ["uns", "unsilent"], ["up", "update"], ["v", "v"], ["ve", "ve"], ["ve", "version"], ["verb", "verbose"], ["version", "version"], ["version", "version"], ["vert", "vertical"], ["vi", "vi"], ["vi", "visual"], ["vie", "view"], ["vim", "vimgrep"], ["vimgrepa", "vimgrepadd"], ["viu", "viusage"], ["vmapc", "vmapclear"], ["vne", "vnew"], ["vs", "vsplit"], ["w", "w"], ["w", "write"], ["wN", "wNext"], ["wa", "wall"], ["wh", "while"], ["win", "win"], ["win", "winsize"], ["winc", "wincmd"], ["windo", "windo"], ["winp", "winpos"], ["wn", "wnext"], ["wp", "wprevious"], ["wq", "wq"], ["wqa", "wqall"], ["ws", "wsverb"], ["wundo", "wundo"], ["wv", "wviminfo"], ["x", "x"], ["x", "xit"], ["xa", "xall"], ["xmapc", "xmapclear"], ["xme", "xme"], ["xmenu", "xmenu"], ["xnoreme", "xnoreme"], ["xnoremenu", "xnoremenu"], ["xterm", "xterm"], ["xunme", "xunme"], ["xunmenu", "xunmenu"], ["xwininfo", "xwininfo"], ["y", "yank"]], :option=>[], :auto=>[["BufAdd", "BufAdd"], ["BufCreate", "BufCreate"], ["BufDelete", "BufDelete"], ["BufEnter", "BufEnter"], ["BufFilePost", "BufFilePost"], ["BufFilePre", "BufFilePre"], ["BufHidden", "BufHidden"], ["BufLeave", "BufLeave"], ["BufNew", "BufNew"], ["BufNewFile", "BufNewFile"], ["BufRead", "BufRead"], ["BufReadCmd", "BufReadCmd"], ["BufReadPost", "BufReadPost"], ["BufReadPre", "BufReadPre"], ["BufUnload", "BufUnload"], ["BufWinEnter", "BufWinEnter"], ["BufWinLeave", "BufWinLeave"], ["BufWipeout", "BufWipeout"], ["BufWrite", "BufWrite"], ["BufWriteCmd", "BufWriteCmd"], ["BufWritePost", "BufWritePost"], ["BufWritePre", "BufWritePre"], ["Cmd", "Cmd"], ["CmdwinEnter", "CmdwinEnter"], ["CmdwinLeave", "CmdwinLeave"], ["ColorScheme", "ColorScheme"], ["CursorHold", "CursorHold"], ["CursorHoldI", "CursorHoldI"], ["CursorMoved", "CursorMoved"], ["CursorMovedI", "CursorMovedI"], ["EncodingChanged", "EncodingChanged"], ["FileAppendCmd", "FileAppendCmd"], ["FileAppendPost", "FileAppendPost"], ["FileAppendPre", "FileAppendPre"], ["FileChangedRO", "FileChangedRO"], ["FileChangedShell", "FileChangedShell"], ["FileChangedShellPost", "FileChangedShellPost"], ["FileEncoding", "FileEncoding"], ["FileReadCmd", "FileReadCmd"], ["FileReadPost", "FileReadPost"], ["FileReadPre", "FileReadPre"], ["FileType", "FileType"], ["FileWriteCmd", "FileWriteCmd"], ["FileWritePost", "FileWritePost"], ["FileWritePre", "FileWritePre"], ["FilterReadPost", "FilterReadPost"], ["FilterReadPre", "FilterReadPre"], ["FilterWritePost", "FilterWritePost"], ["FilterWritePre", "FilterWritePre"], ["FocusGained", "FocusGained"], ["FocusLost", "FocusLost"], ["FuncUndefined", "FuncUndefined"], ["GUIEnter", "GUIEnter"], ["GUIFailed", "GUIFailed"], ["InsertChange", "InsertChange"], ["InsertCharPre", "InsertCharPre"], ["InsertEnter", "InsertEnter"], ["InsertLeave", "InsertLeave"], ["MenuPopup", "MenuPopup"], ["QuickFixCmdPost", "QuickFixCmdPost"], ["QuickFixCmdPre", "QuickFixCmdPre"], ["RemoteReply", "RemoteReply"], ["SessionLoadPost", "SessionLoadPost"], ["ShellCmdPost", "ShellCmdPost"], ["ShellFilterPost", "ShellFilterPost"], ["SourceCmd", "SourceCmd"], ["SourcePre", "SourcePre"], ["SpellFileMissing", "SpellFileMissing"], ["StdinReadPost", "StdinReadPost"], ["StdinReadPre", "StdinReadPre"], ["SwapExists", "SwapExists"], ["Syntax", "Syntax"], ["TabEnter", "TabEnter"], ["TabLeave", "TabLeave"], ["TermChanged", "TermChanged"], ["TermResponse", "TermResponse"], ["User", "User"], ["UserGettingBored", "UserGettingBored"], ["VimEnter", "VimEnter"], ["VimLeave", "VimLeave"], ["VimLeavePre", "VimLeavePre"], ["VimResized", "VimResized"], ["WinEnter", "WinEnter"], ["WinLeave", "WinLeave"], ["event", "event"]]}
+      end
+    end
+  end
+end

spec/lexers/viml_spec.rb

@@ -0,0 +1,44 @@
+describe Rouge::Lexers::VimL do
+  let(:subject) { Rouge::Lexers::VimL.new }
+
+  describe 'mapping binary search' do
+    let(:mapping) {
+      [['aa', 'aaa'],
+       ['bb', 'bb'],
+       ['cc', 'ccc']]
+    }
+
+    it 'finds a likely mapping' do
+      likely = subject.find_likely_mapping(mapping, 'aa')
+      assert { likely == ['aa', 'aaa'] }
+
+      likely = subject.find_likely_mapping(mapping, 'abc')
+      assert { likely == ['aa', 'aaa'] }
+
+      likely = subject.find_likely_mapping(mapping, 'bbbbb')
+      assert { likely == ['bb', 'bb'] }
+
+      likely = subject.find_likely_mapping(mapping, 'z')
+      assert { likely == ['cc', 'ccc'] }
+    end
+  end
+
+  describe 'guessing' do
+    include Support::Guessing
+
+    it 'guesses by filename' do
+      assert_guess :filename => 'foo.vim'
+      assert_guess :filename => 'foo.vba'
+      assert_guess :filename => '~/.vimrc'
+      assert_guess :filename => '.exrc'
+      assert_guess :filename => '.gvimrc'
+      assert_guess :filename => '_vimrc'
+      assert_guess :filename => '_gvimrc'
+      assert_guess :filename => '_exrc'
+    end
+
+    it 'guesses by mimetype' do
+      assert_guess :mimetype => 'text/x-vim'
+    end
+  end
+end