diff options
| -rw-r--r-- | spec/util_promise_spec.lua | 51 | ||||
| -rw-r--r-- | util/promise.lua | 6 |
2 files changed, 57 insertions, 0 deletions
diff --git a/spec/util_promise_spec.lua b/spec/util_promise_spec.lua index 778a7661..c2a8ba95 100644 --- a/spec/util_promise_spec.lua +++ b/spec/util_promise_spec.lua @@ -331,4 +331,55 @@ describe("util.promise", function () assert.spy(on_finally_err).was_called_with(test_error); end); end); + describe("try()", function () + it("works with functions that return a promise", function () + local resolve; + local p = promise.try(function () + return promise.new(function (_resolve) + resolve = _resolve; + end); + end); + assert.is_function(resolve); + local on_resolved = spy.new(function () end); + p:next(on_resolved); + assert.spy(on_resolved).was_not_called(); + resolve("foo"); + assert.spy(on_resolved).was_called_with("foo"); + end); + + it("works with functions that return a value", function () + local p = promise.try(function () + return "foo"; + end); + local on_resolved = spy.new(function () end); + p:next(on_resolved); + assert.spy(on_resolved).was_called_with("foo"); + end); + + it("works with functions that return a promise that rejects", function () + local reject; + local p = promise.try(function () + return promise.new(function (_, _reject) + reject = _reject; + end); + end); + assert.is_function(reject); + local on_rejected = spy.new(function () end); + p:catch(on_rejected); + assert.spy(on_rejected).was_not_called(); + reject("foo"); + assert.spy(on_rejected).was_called_with("foo"); + end); + + it("works with functions that throw errors", function () + local test_error = {}; + local p = promise.try(function () + error(test_error); + end); + local on_rejected = spy.new(function () end); + p:catch(on_rejected); + assert.spy(on_rejected).was_called(1); + assert.spy(on_rejected).was_called_with(test_error); + end); + end); end); diff --git a/util/promise.lua b/util/promise.lua index b5660488..b1c6be02 100644 --- a/util/promise.lua +++ b/util/promise.lua @@ -51,6 +51,7 @@ local function new_resolve_functions(p) if resolved then return; end resolved = true; if is_promise(e) then + print ("WOAH") assert(false) e:next(new_resolve_functions(p)); elseif promise_settle(p, "rejected", next_rejected, p._pending_on_rejected, e) then p.reason = e; @@ -117,6 +118,10 @@ local function reject(v) end); end +local function try(f) + return resolve():next(function () return f(); end); +end + function promise_methods:next(on_fulfilled, on_rejected) return new(function (resolve, reject) --luacheck: ignore 431/resolve 431/reject self:_next( @@ -142,4 +147,5 @@ return { reject = reject; all = all; race = race; + try = try; } |