prosody
8ef46d09386a
util/promise.lua

Find changesets by keywords by author, files, the commit message, revision number or hash, or revset expression.

Software / code / prosody

Annotate

util/promise.lua @ 9510:8ef46d09386a

util.promise: Fix promise.reject() to return a rejected promise, and fix buggy test for it
author Matthew Wild <mwild1@gmail.com>
date Thu, 18 Oct 2018 12:03:33 +0100
parent 9456:d54a0e129af8
child 9512:439cf3bbe5f3
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
rev   line source
9456
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
1 local promise_methods = {};
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
2 local promise_mt = { __name = "promise", __index = promise_methods };
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
3
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
4 local function is_promise(o)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
5 local mt = getmetatable(o);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
6 return mt == promise_mt;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
7 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
8
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
9 local function next_pending(self, on_fulfilled, on_rejected)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
10 table.insert(self._pending_on_fulfilled, on_fulfilled);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
11 table.insert(self._pending_on_rejected, on_rejected);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
12 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
13
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
14 local function next_fulfilled(promise, on_fulfilled, on_rejected) -- luacheck: ignore 212/on_rejected
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
15 on_fulfilled(promise.value);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
16 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
17
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
18 local function next_rejected(promise, on_fulfilled, on_rejected) -- luacheck: ignore 212/on_fulfilled
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
19 on_rejected(promise.reason);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
20 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
21
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
22 local function promise_settle(promise, new_state, new_next, cbs, value)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
23 if promise._state ~= "pending" then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
24 return;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
25 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
26 promise._state = new_state;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
27 promise._next = new_next;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
28 for _, cb in ipairs(cbs) do
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
29 cb(value);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
30 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
31 return true;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
32 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
33
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
34 local function new_resolve_functions(p)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
35 local resolved = false;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
36 local function _resolve(v)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
37 if resolved then return; end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
38 resolved = true;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
39 if is_promise(v) then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
40 v:next(new_resolve_functions(p));
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
41 elseif promise_settle(p, "fulfilled", next_fulfilled, p._pending_on_fulfilled, v) then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
42 p.value = v;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
43 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
44
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
45 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
46 local function _reject(e)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
47 if resolved then return; end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
48 resolved = true;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
49 if promise_settle(p, "rejected", next_rejected, p._pending_on_rejected, e) then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
50 p.reason = e;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
51 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
52 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
53 return _resolve, _reject;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
54 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
55
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
56 local function new(f)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
57 local p = setmetatable({ _state = "pending", _next = next_pending, _pending_on_fulfilled = {}, _pending_on_rejected = {} }, promise_mt);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
58 if f then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
59 local resolve, reject = new_resolve_functions(p);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
60 local ok, ret = pcall(f, resolve, reject);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
61 if not ok and p._state == "pending" then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
62 reject(ret);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
63 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
64 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
65 return p;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
66 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
67
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
68 local function wrap_handler(f, resolve, reject)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
69 return function (param)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
70 local ok, ret = pcall(f, param);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
71 if ok then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
72 resolve(ret);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
73 else
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
74 reject(ret);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
75 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
76 end;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
77 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
78
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
79 function promise_methods:next(on_fulfilled, on_rejected)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
80 return new(function (resolve, reject)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
81 self:_next(
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
82 on_fulfilled and wrap_handler(on_fulfilled, resolve, reject) or nil,
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
83 on_rejected and wrap_handler(on_rejected, resolve, reject) or nil
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
84 );
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
85 end);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
86 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
87
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
88 function promise_methods:catch(on_rejected)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
89 return self:next(nil, on_rejected);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
90 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
91
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
92 local function all(promises)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
93 return new(function (resolve, reject)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
94 local count, total, results = 0, #promises, {};
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
95 for i = 1, total do
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
96 promises[i]:next(function (v)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
97 results[i] = v;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
98 count = count + 1;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
99 if count == total then
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
100 resolve(results);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
101 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
102 end, reject);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
103 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
104 end);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
105 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
106
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
107 local function race(promises)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
108 return new(function (resolve, reject)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
109 for i = 1, #promises do
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
110 promises[i]:next(resolve, reject);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
111 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
112 end);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
113 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
114
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
115 local function resolve(v)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
116 return new(function (_resolve)
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
117 _resolve(v);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
118 end);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
119 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
120
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
121 local function reject(v)
9510
8ef46d09386a util.promise: Fix promise.reject() to return a rejected promise, and fix buggy test for it
Matthew Wild <mwild1@gmail.com>
parents: 9456
diff changeset
122 return new(function (_, _reject)
9456
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
123 _reject(v);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
124 end);
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
125 end
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
126
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
127 return {
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
128 new = new;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
129 resolve = resolve;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
130 reject = reject;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
131 all = all;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
132 race = race;
d54a0e129af8 util.promise: ES6-like API for promises
Matthew Wild <mwild1@gmail.com>
parents:
diff changeset
133 }