gwynne commented 3 years ago

These new variants guarantee two specific behaviors:

The futures returned for each element of the iterated sequence will be executed singularly and strictly in order. Only one will run at a time, and the order in which they run will match that returned by the transformation callback.
If any one of the futures should fail, no other futures will begin execution, even if they were ready to do so.

Additional changes:

Added new tests for the "sequenced" behaviors,
Made sure the ELG used for the collections+futures tests has multiple threads, otherwise the tests are meaningless.
Fixed a couple of typos in comments.
Simplified the implementations of the original flatMapEach(on:_:) and flatMapEachCompact(on:_:) (no functional changes).

codecov-io commented 3 years ago

Codecov Report

Merging #73 (47e4dfa) into master (6184c6c) will increase coverage by 0.20%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master      #73      +/-   ##
==========================================
+ Coverage   94.76%   94.97%   +0.20%     
==========================================
  Files          23       23              
  Lines        1204     1254      +50     
==========================================
+ Hits         1141     1191      +50     
  Misses         63       63

Flag	Coverage Δ
unittests	`94.97% <100.00%> (+0.20%)`	:arrow_up:

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Impacted Files	Coverage Δ
...s/AsyncKit/EventLoopFuture/Future+Collection.swift	`100.00% <100.00%> (ø)`
Tests/AsyncKitTests/Future+CollectionTests.swift	`100.00% <100.00%> (ø)`

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MrMage commented 3 years ago

I think Vapor used to have methods for this already. Or was that only in Vapor 3's "core" repository? I might also be mistaken completely.

But I wonder if the SwiftNIO people would be interested in taking this as a PR for their repo, so that it can benefit everyone by default. At least in the past they used to be fairly open to such additions, IIRC. /cc @weissi @lukasa

tanner0101 commented 3 years ago

These changes are now available in 1.3.0

vapor / async-kit

Add "sequenced" variants of flatMapEach() and flatMapEachCompact() #73

Codecov Report