diff options
| author | Mike Vink <mike@pionative.com> | 2025-02-03 21:29:42 +0100 |
|---|---|---|
| committer | Mike Vink <mike@pionative.com> | 2025-02-03 21:29:42 +0100 |
| commit | 5155816b7b925dec5d5feb1568b1d7ceb00938b9 (patch) | |
| tree | deca28ea15e79f6f804c3d90d2ba757881638af5 /src/luarocks/core/util.lua | |
Diffstat (limited to 'src/luarocks/core/util.lua')
| -rw-r--r-- | src/luarocks/core/util.lua | 322 |
1 files changed, 322 insertions, 0 deletions
diff --git a/src/luarocks/core/util.lua b/src/luarocks/core/util.lua new file mode 100644 index 0000000..e9abdd3 --- /dev/null +++ b/src/luarocks/core/util.lua @@ -0,0 +1,322 @@ + +local util = {} + +local require = nil +-------------------------------------------------------------------------------- + +local dir_sep = package.config:sub(1, 1) + +--- Run a process and read a its output. +-- Equivalent to io.popen(cmd):read("*l"), except that it +-- closes the fd right away. +-- @param cmd string: The command to execute +-- @param spec string: "*l" by default, to read a single line. +-- May be used to read more, passing, for instance, "*a". +-- @return string: the output of the program. +function util.popen_read(cmd, spec) + local tmpfile = (dir_sep == "\\") + and (os.getenv("TMP") .. "/luarocks-" .. tostring(math.floor(math.random() * 10000))) + or os.tmpname() + os.execute(cmd .. " > " .. tmpfile) + local fd = io.open(tmpfile, "rb") + if not fd then + os.remove(tmpfile) + return "" + end + local out = fd:read(spec or "*l") + fd:close() + os.remove(tmpfile) + return out or "" +end + +--- +-- Formats tables with cycles recursively to any depth. +-- References to other tables are shown as values. +-- Self references are indicated. +-- The string returned is "Lua code", which can be processed +-- (in the case in which indent is composed by spaces or "--"). +-- Userdata and function keys and values are shown as strings, +-- which logically are exactly not equivalent to the original code. +-- This routine can serve for pretty formating tables with +-- proper indentations, apart from printing them: +-- io.write(table.show(t, "t")) -- a typical use +-- Written by Julio Manuel Fernandez-Diaz, +-- Heavily based on "Saving tables with cycles", PIL2, p. 113. +-- @param t table: is the table. +-- @param tname string: is the name of the table (optional) +-- @param top_indent string: is a first indentation (optional). +-- @return string: the pretty-printed table +function util.show_table(t, tname, top_indent) + local cart -- a container + local autoref -- for self references + + local function is_empty_table(tbl) return next(tbl) == nil end + + local function basic_serialize(o) + local so = tostring(o) + if type(o) == "function" then + local info = debug and debug.getinfo(o, "S") + if not info then + return ("%q"):format(so) + end + -- info.name is nil because o is not a calling level + if info.what == "C" then + return ("%q"):format(so .. ", C function") + else + -- the information is defined through lines + return ("%q"):format(so .. ", defined in (" .. info.linedefined .. "-" .. info.lastlinedefined .. ")" .. info.source) + end + elseif type(o) == "number" then + return so + else + return ("%q"):format(so) + end + end + + local function add_to_cart(value, name, indent, saved, field) + indent = indent or "" + saved = saved or {} + field = field or name + + cart = cart .. indent .. field + + if type(value) ~= "table" then + cart = cart .. " = " .. basic_serialize(value) .. ";\n" + else + if saved[value] then + cart = cart .. " = {}; -- " .. saved[value] .. " (self reference)\n" + autoref = autoref .. name .. " = " .. saved[value] .. ";\n" + else + saved[value] = name + if is_empty_table(value) then + cart = cart .. " = {};\n" + else + cart = cart .. " = {\n" + for k, v in pairs(value) do + k = basic_serialize(k) + local fname = ("%s[%s]"):format(name, k) + field = ("[%s]"):format(k) + -- three spaces between levels + add_to_cart(v, fname, indent .. " ", saved, field) + end + cart = cart .. indent .. "};\n" + end + end + end + end + + tname = tname or "__unnamed__" + if type(t) ~= "table" then + return tname .. " = " .. basic_serialize(t) + end + cart, autoref = "", "" + add_to_cart(t, tname, top_indent) + return cart .. autoref +end + +--- Merges contents of src on top of dst's contents +-- (i.e. if an key from src already exists in dst, replace it). +-- @param dst Destination table, which will receive src's contents. +-- @param src Table which provides new contents to dst. +function util.deep_merge(dst, src) + for k, v in pairs(src) do + if type(v) == "table" then + if dst[k] == nil then + dst[k] = {} + end + if type(dst[k]) == "table" then + util.deep_merge(dst[k], v) + else + dst[k] = v + end + else + dst[k] = v + end + end +end + +--- Merges contents of src below those of dst's contents +-- (i.e. if an key from src already exists in dst, do not replace it). +-- @param dst Destination table, which will receive src's contents. +-- @param src Table which provides new contents to dst. +function util.deep_merge_under(dst, src) + for k, v in pairs(src) do + if type(v) == "table" then + if dst[k] == nil then + dst[k] = {} + end + if type(dst[k]) == "table" then + util.deep_merge_under(dst[k], v) + end + elseif dst[k] == nil then + dst[k] = v + end + end +end + +--- Clean up a path-style string ($PATH, $LUA_PATH/package.path, etc.), +-- removing repeated entries and making sure only the relevant +-- Lua version is used. +-- Example: given ("a;b;c;a;b;d", ";"), returns "a;b;c;d". +-- @param list string: A path string (from $PATH or package.path) +-- @param sep string: The separator +-- @param lua_version (optional) string: The Lua version to use. +-- @param keep_first (optional) if true, keep first occurrence in case +-- of duplicates; otherwise keep last occurrence. The default is false. +function util.cleanup_path(list, sep, lua_version, keep_first) + assert(type(list) == "string") + assert(type(sep) == "string") + + list = list:gsub(dir_sep, "/") + + local parts = util.split_string(list, sep) + local final, entries = {}, {} + local start, stop, step + + if keep_first then + start, stop, step = 1, #parts, 1 + else + start, stop, step = #parts, 1, -1 + end + + for i = start, stop, step do + local part = parts[i]:gsub("//", "/") + if lua_version then + part = part:gsub("/lua/([%d.]+)/", function(part_version) + if part_version:sub(1, #lua_version) ~= lua_version then + return "/lua/"..lua_version.."/" + end + end) + end + if not entries[part] then + local at = keep_first and #final+1 or 1 + table.insert(final, at, part) + entries[part] = true + end + end + + return (table.concat(final, sep):gsub("/", dir_sep)) +end + +-- from http://lua-users.org/wiki/SplitJoin +-- by Philippe Lhoste +function util.split_string(str, delim, maxNb) + -- Eliminate bad cases... + if string.find(str, delim) == nil then + return { str } + end + if maxNb == nil or maxNb < 1 then + maxNb = 0 -- No limit + end + local result = {} + local pat = "(.-)" .. delim .. "()" + local nb = 0 + local lastPos + for part, pos in string.gmatch(str, pat) do + nb = nb + 1 + result[nb] = part + lastPos = pos + if nb == maxNb then break end + end + -- Handle the last field + if nb ~= maxNb then + result[nb + 1] = string.sub(str, lastPos) + end + return result +end + +--- Return an array of keys of a table. +-- @param tbl table: The input table. +-- @return table: The array of keys. +function util.keys(tbl) + local ks = {} + for k,_ in pairs(tbl) do + table.insert(ks, k) + end + return ks +end + +--- Print a line to standard error +function util.printerr(...) + io.stderr:write(table.concat({...},"\t")) + io.stderr:write("\n") +end + +--- Display a warning message. +-- @param msg string: the warning message +function util.warning(msg) + util.printerr("Warning: "..msg) +end + +--- Simple sort function used as a default for util.sortedpairs. +local function default_sort(a, b) + local ta = type(a) + local tb = type(b) + if ta == "number" and tb == "number" then + return a < b + elseif ta == "number" then + return true + elseif tb == "number" then + return false + else + return tostring(a) < tostring(b) + end +end + +--- A table iterator generator that returns elements sorted by key, +-- to be used in "for" loops. +-- @param tbl table: The table to be iterated. +-- @param sort_function function or table or nil: An optional comparison function +-- to be used by table.sort when sorting keys, or an array listing an explicit order +-- for keys. If a value itself is an array, it is taken so that the first element +-- is a string representing the field name, and the second element is a priority table +-- for that key, which is returned by the iterator as the third value after the key +-- and the value. +-- @return function: the iterator function. +function util.sortedpairs(tbl, sort_function) + sort_function = sort_function or default_sort + local keys = util.keys(tbl) + local sub_orders = {} + + if type(sort_function) == "function" then + table.sort(keys, sort_function) + else + local order = sort_function + local ordered_keys = {} + local all_keys = keys + keys = {} + + for _, order_entry in ipairs(order) do + local key, sub_order + if type(order_entry) == "table" then + key = order_entry[1] + sub_order = order_entry[2] + else + key = order_entry + end + + if tbl[key] then + ordered_keys[key] = true + sub_orders[key] = sub_order + table.insert(keys, key) + end + end + + table.sort(all_keys, default_sort) + for _, key in ipairs(all_keys) do + if not ordered_keys[key] then + table.insert(keys, key) + end + end + end + + local i = 1 + return function() + local key = keys[i] + i = i + 1 + return key, tbl[key], sub_orders[key] + end +end + +return util + |
