feat(core): new utils.promise.array_filter function

adaltas · Mar 1, 2021 · 8793cb3 · 8793cb3
1 parent e89ada5
commit 8793cb3
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Showing 3 changed files with 33 additions and 4 deletions.
diff --git a/packages/core/lib/utils/promise.js b/packages/core/lib/utils/promise.js
diff --git a/packages/core/src/utils/promise.coffee b/packages/core/src/utils/promise.coffee
@@ -1,5 +1,11 @@
 
 module.exports =
+ array_filter: (arr, handler) ->
+ fail = Symbol()
+ (
+ await Promise.all arr.map (item) ->
+ if await handler(item) then item else fail
+ ).filter (i) -> i isnt fail
  is: (obj) ->
  # promise && !!promise.then
  return !!obj and (typeof obj is 'object' || typeof obj is 'function') and typeof obj.then is 'function'
diff --git a/packages/core/test/utils/promise.coffee b/packages/core/test/utils/promise.coffee
@@ -4,9 +4,19 @@ promise = require '../../src/utils/promise'
 
 describe 'utils.promise', ->
  return unless tags.api
+
+ describe 'array_filter', ->
+
+ it 'filter', ->
+ result = await promise.array_filter [1,2,3,4], (el) ->
+ new Promise (resolve) ->
+ setImmediate -> resolve el % 2 is 0
+ result.should.eql [2, 4]
+
+ describe 'is', ->
 
- it 'true', ->
- promise.is(new Promise (->)).should.be.true()
+  it 'true', ->
+  promise.is(new Promise (->)).should.be.true()
 
- it 'false', ->
- promise.is({}).should.be.false()
+  it 'false', ->
+  promise.is({}).should.be.false()