1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
-- Trace module calls and method calls on created objects
--
-- Very rough and for debugging purposes only. It makes many
-- assumptions and there are many ways it could fail.
--
-- Example use:
--
-- local dbuffer = require "tools.modtrace".trace("util.dbuffer");
--
local t_pack = table.pack;
local serialize = require "util.serialization".serialize;
local unpack = table.unpack;
local set = require "util.set";
local serialize_cfg = {
preset = "oneline";
freeze = true;
fatal = false;
fallback = function (v) return "<"..tostring(v)..">" end;
};
local function stringify_value(v)
if type(v) == "string" and #v > 20 then
return ("<string(%d)>"):format(#v);
elseif type(v) == "function" then
return tostring(v);
end
return serialize(v, serialize_cfg);
end
local function stringify_params(...)
local n = select("#", ...);
local r = {};
for i = 1, n do
table.insert(r, stringify_value((select(i, ...))));
end
return table.concat(r, ", ");
end
local function stringify_result(ret)
local r = {};
for i = 1, ret.n do
table.insert(r, stringify_value(ret[i]));
end
return table.concat(r, ", ");
end
local function stringify_call(method_name, ...)
return ("%s(%s)"):format(method_name, stringify_params(...));
end
local function wrap_method(original_obj, original_method, method_name)
method_name = ("<%s>:%s"):format(getmetatable(original_obj).__name or "object", method_name);
return function (new_obj_self, ...)
local opts = new_obj_self._modtrace_opts;
local f = opts.output or io.stderr;
f:write(stringify_call(method_name, ...));
local ret = t_pack(original_method(original_obj, ...));
if ret.n > 0 then
f:write(" = ", stringify_result(ret), "\n");
else
f:write("\n");
end
return unpack(ret, 1, ret.n);
end;
end
local function wrap_function(original_function, function_name, opts)
local f = opts.output or io.stderr;
return function (...)
f:write(stringify_call(function_name, ...));
local ret = t_pack(original_function(...));
if ret.n > 0 then
f:write(" = ", stringify_result(ret), "\n");
else
f:write("\n");
end
return unpack(ret, 1, ret.n);
end;
end
local function wrap_metamethod(name, method)
if name == "__index" then
return function (new_obj, k)
local original_method;
if type(method) == "table" then
original_method = new_obj._modtrace_original_obj[k];
else
original_method = method(new_obj._modtrace_original_obj, k);
end
if original_method == nil then
return nil;
end
return wrap_method(new_obj._modtrace_original_obj, original_method, k);
end;
end
return function (new_obj, ...)
return method(new_obj._modtrace_original_obj, ...);
end;
end
local function wrap_mt(original_mt)
local new_mt = {};
for k, v in pairs(original_mt) do
new_mt[k] = wrap_metamethod(k, v);
end
return new_mt;
end
local function wrap_obj(original_obj, opts)
local new_mt = wrap_mt(getmetatable(original_obj));
return setmetatable({_modtrace_original_obj = original_obj, _modtrace_opts = opts}, new_mt);
end
local function wrap_new(original_new, function_name, opts)
local f = opts.output or io.stderr;
return function (...)
f:write(stringify_call(function_name, ...));
local ret = t_pack(original_new(...));
local obj = ret[1];
if ret.n == 1 and type(ret[1]) == "table" then
f:write(" = <", getmetatable(ret[1]).__name or "object", ">", "\n");
elseif ret.n > 0 then
f:write(" = ", stringify_result(ret), "\n");
else
f:write("\n");
end
if obj then
ret[1] = wrap_obj(obj, opts);
end
return unpack(ret, 1, ret.n);
end;
end
local function trace(module, opts)
if type(module) == "string" then
module = require(module);
end
opts = opts or {};
local new_methods = set.new(opts.new_methods or {"new"});
local fake_module = setmetatable({}, {
__index = function (_, k)
if new_methods:contains(k) then
return wrap_new(module[k], k, opts);
else
return wrap_function(module[k], k, opts);
end
end;
});
return fake_module;
end
return {
wrap = trace;
trace = trace;
}
|
