Make dump's output prettier

Changes:
  * Indentation with tabs by default.
  * Array keys dumped without "[i] = " prefix.
  * String keys that are valid identifiers aren't enclosed in '[""]'.
  * Basic support for multiple references (as specified in the comment).

diff --git a/builtin/common/misc_helpers.lua b/builtin/common/misc_helpers.lua
index f57efc138dc2cd1a92535254a70fedaa00c943d6..2e2eac925ba11b763d621cd847858f6673c31db0 100644 (file)
--- a/builtin/common/misc_helpers.lua
+++ b/builtin/common/misc_helpers.lua
@@ -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:
@@ -70,33 +101,57 @@ 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("\t", level - 1)
+               return string.format("{%s%s%s}",
+                               indent_str,
+                               table.concat(t, ","..indent_str),
+                               end_indent_str)
+       end
+       return "{"..table.concat(t, ", ").."}"
 end
 
 --------------------------------------------------------------------------------