]> git.lizzy.rs Git - minetest.git/blobdiff - builtin/common/misc_helpers.lua
Fix imprecise serialization of large numbers
[minetest.git] / builtin / common / misc_helpers.lua
index f57efc138dc2cd1a92535254a70fedaa00c943d6..deeba788ea49ae551e62c6b7f550b0556f1479c7 100644 (file)
@@ -21,6 +21,37 @@ function basic_dump(o)
        end
 end
 
+local keywords = {
+       ["and"] = true,
+       ["break"] = true,
+       ["do"] = true,
+       ["else"] = true,
+       ["elseif"] = true,
+       ["end"] = true,
+       ["false"] = true,
+       ["for"] = true,
+       ["function"] = true,
+       ["goto"] = true,  -- Lua 5.2
+       ["if"] = true,
+       ["in"] = true,
+       ["local"] = true,
+       ["nil"] = true,
+       ["not"] = true,
+       ["or"] = true,
+       ["repeat"] = true,
+       ["return"] = true,
+       ["then"] = true,
+       ["true"] = true,
+       ["until"] = true,
+       ["while"] = true,
+}
+local function is_valid_identifier(str)
+       if not str:find("^[a-zA-Z_][a-zA-Z0-9_]*$") or keywords[str] then
+               return false
+       end
+       return true
+end
+
 --------------------------------------------------------------------------------
 -- Dumps values in a line-per-value format.
 -- For example, {test = {"Testing..."}} becomes:
@@ -70,41 +101,85 @@ function dump2(o, name, dumped)
 end
 
 --------------------------------------------------------------------------------
--- This dumps values in a one-line format, like serialize().
--- For example, {test = {"Testing..."}} becomes {["test"] = {[1] = "Testing..."}}
+-- This dumps values in a one-statement format.
+-- For example, {test = {"Testing..."}} becomes:
+-- [[{
+--     test = {
+--             "Testing..."
+--     }
+-- }]]
 -- This supports tables as keys, but not circular references.
 -- It performs poorly with multiple references as it writes out the full
 -- table each time.
--- The dumped argument is internal-only.
+-- The indent field specifies a indentation string, it defaults to a tab.
+-- Use the empty string to disable indentation.
+-- The dumped and level arguments are internal-only.
 
-function dump(o, dumped)
-       -- Same as "dumped" in dump2.  The difference is that here it can only
-       -- contain boolean (and nil) values since multiple references aren't
-       -- handled properly.
-       dumped = dumped or {}
-       if type(o) == "table" then
-               if dumped[o] then
-                       return "<circular reference>"
-               end
-               dumped[o] = true
-               local t = {}
-               for k, v in pairs(o) do
-                       k = dump(k, dumped)
-                       v = dump(v, dumped)
-                       table.insert(t, string.format("[%s] = %s", k, v))
-               end
-               return string.format("{%s}", table.concat(t, ", "))
-       else
+function dump(o, indent, nested, level)
+       if type(o) ~= "table" then
                return basic_dump(o)
        end
+       -- Contains table -> true/nil of currently nested tables
+       nested = nested or {}
+       if nested[o] then
+               return "<circular reference>"
+       end
+       nested[o] = true
+       indent = indent or "\t"
+       level = level or 1
+       local t = {}
+       local dumped_indexes = {}
+       for i, v in ipairs(o) do
+               table.insert(t, dump(v, indent, nested, level + 1))
+               dumped_indexes[i] = true
+       end
+       for k, v in pairs(o) do
+               if not dumped_indexes[k] then
+                       if type(k) ~= "string" or not is_valid_identifier(k) then
+                               k = "["..dump(k, indent, nested, level + 1).."]"
+                       end
+                       v = dump(v, indent, nested, level + 1)
+                       table.insert(t, k.." = "..v)
+               end
+       end
+       nested[o] = nil
+       if indent ~= "" then
+               local indent_str = "\n"..string.rep(indent, level)
+               local end_indent_str = "\n"..string.rep(indent, level - 1)
+               return string.format("{%s%s%s}",
+                               indent_str,
+                               table.concat(t, ","..indent_str),
+                               end_indent_str)
+       end
+       return "{"..table.concat(t, ", ").."}"
 end
 
 --------------------------------------------------------------------------------
-function string:split(sep)
-       local sep, fields = sep or ",", {}
-       local pattern = string.format("([^%s]+)", sep)
-       self:gsub(pattern, function(c) fields[#fields+1] = c end)
-       return fields
+-- Localize functions to avoid table lookups (better performance).
+local table_insert = table.insert
+local str_sub, str_find = string.sub, string.find
+function string.split(str, delim, include_empty, max_splits, sep_is_pattern)
+       delim = delim or ","
+       max_splits = max_splits or -1
+       local items = {}
+       local pos, len, seplen = 1, #str, #delim
+       local plain = not sep_is_pattern
+       max_splits = max_splits + 1
+       repeat
+               local np, npe = str_find(str, delim, pos, plain)
+               np, npe = (np or (len+1)), (npe or (len+1))
+               if (not np) or (max_splits == 1) then
+                       np = len + 1
+                       npe = np
+               end
+               local s = str_sub(str, pos, np - 1)
+               if include_empty or (s ~= "") then
+                       max_splits = max_splits - 1
+                       table_insert(items, s)
+               end
+               pos = npe + 1
+       until (max_splits == 0) or (pos > (len + 1))
+       return items
 end
 
 --------------------------------------------------------------------------------
@@ -137,6 +212,17 @@ function math.hypot(x, y)
        return x * math.sqrt(1 + t * t)
 end
 
+--------------------------------------------------------------------------------
+function math.sign(x, tolerance)
+       tolerance = tolerance or 0
+       if x > tolerance then
+               return 1
+       elseif x < -tolerance then
+               return -1
+       end
+       return 0
+end
+
 --------------------------------------------------------------------------------
 function get_last_folder(text,count)
        local parts = text:split(DIR_DELIM)
@@ -377,7 +463,8 @@ function core.explode_table_event(evt)
                        local t = parts[1]:trim()
                        local r = tonumber(parts[2]:trim())
                        local c = tonumber(parts[3]:trim())
-                       if type(r) == "number" and type(c) == "number" and t ~= "INV" then
+                       if type(r) == "number" and type(c) == "number"
+                                       and t ~= "INV" then
                                return {type=t, row=r, column=c}
                        end
                end
@@ -411,8 +498,57 @@ function core.explode_scrollbar_event(evt)
 end
 
 --------------------------------------------------------------------------------
-function core.pos_to_string(pos)
-       return "(" .. pos.x .. "," .. pos.y .. "," .. pos.z .. ")"
+function core.pos_to_string(pos, decimal_places)
+       local x = pos.x
+       local y = pos.y
+       local z = pos.z
+       if decimal_places ~= nil then
+               x = string.format("%." .. decimal_places .. "f", x)
+               y = string.format("%." .. decimal_places .. "f", y)
+               z = string.format("%." .. decimal_places .. "f", z)
+       end
+       return "(" .. x .. "," .. y .. "," .. z .. ")"
+end
+
+--------------------------------------------------------------------------------
+function core.string_to_pos(value)
+       if value == nil then
+               return nil
+       end
+
+       local p = {}
+       p.x, p.y, p.z = string.match(value, "^([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+)$")
+       if p.x and p.y and p.z then
+               p.x = tonumber(p.x)
+               p.y = tonumber(p.y)
+               p.z = tonumber(p.z)
+               return p
+       end
+       local p = {}
+       p.x, p.y, p.z = string.match(value, "^%( *([%d.-]+)[, ] *([%d.-]+)[, ] *([%d.-]+) *%)$")
+       if p.x and p.y and p.z then
+               p.x = tonumber(p.x)
+               p.y = tonumber(p.y)
+               p.z = tonumber(p.z)
+               return p
+       end
+       return nil
+end
+
+assert(core.string_to_pos("10.0, 5, -2").x == 10)
+assert(core.string_to_pos("( 10.0, 5, -2)").z == -2)
+assert(core.string_to_pos("asd, 5, -2)") == nil)
+
+--------------------------------------------------------------------------------
+function table.copy(t, seen)
+       local n = {}
+       seen = seen or {}
+       seen[t] = n
+       for k, v in pairs(t) do
+               n[type(k) ~= "table" and k or seen[k] or table.copy(k, seen)] =
+                       type(v) ~= "table" and v or seen[v] or table.copy(v, seen)
+       end
+       return n
 end
 
 --------------------------------------------------------------------------------
@@ -434,16 +570,18 @@ if INIT == "mainmenu" then
                local arg = {n=select('#', ...), ...}
                if arg.n >= 1 then
                        -- Insert positional parameters ($1, $2, ...)
-                       result = ''
-                       pos = 1
+                       local result = ''
+                       local pos = 1
                        while pos <= text:len() do
-                               newpos = text:find('[$]', pos)
+                               local newpos = text:find('[$]', pos)
                                if newpos == nil then
                                        result = result .. text:sub(pos)
                                        pos = text:len() + 1
                                else
-                                       paramindex = tonumber(text:sub(newpos+1, newpos+1))
-                                       result = result .. text:sub(pos, newpos-1) .. tostring(arg[paramindex])
+                                       local paramindex =
+                                               tonumber(text:sub(newpos+1, newpos+1))
+                                       result = result .. text:sub(pos, newpos-1)
+                                               .. tostring(arg[paramindex])
                                        pos = newpos + 2
                                end
                        end