Make Promise.Sequence report progress.

njannink · Feb 18, 2018 · 9f49b4b · 9f49b4b
1 parent 0c9908a
commit 9f49b4b
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Showing 2 changed files with 66 additions and 3 deletions.
diff --git a/Promise_NonGeneric.cs b/Promise_NonGeneric.cs
@@ -1001,10 +1001,37 @@ public static IPromise Sequence(params Func<IPromise>[] fns)
         /// </summary>
         public static IPromise Sequence(IEnumerable<Func<IPromise>> fns)
         {
-            return fns.Aggregate(
+            var promise = new Promise();
+
+            int count = 0;
+
+            fns.Aggregate(
                 Resolved(),
-                (prevPromise, fn) => prevPromise.Then(fn)
-            );
+                (prevPromise, fn) =>
+                {
+                    int itemSequence = count;
+                    ++count;
+
+                    return prevPromise
+                            .Then(() =>
+                            {
+                                var sliceLength = 1f / count;
+                                promise.ReportProgress(sliceLength * itemSequence);
+                                return fn();
+                            })
+                            .Progress(v =>
+                            {
+                                var sliceLength = 1f / count;
+                                promise.ReportProgress(sliceLength * (v + itemSequence));
+                            })
+                    ;
+                }
+            )
+            .Then(() => promise.Resolve())
+            .Catch(promise.Reject)
+            .Done();
+
+            return promise;
         }
 
         /// <summary>

diff --git a/Tests/Promise_NonGeneric_ProgressTests.cs b/Tests/Promise_NonGeneric_ProgressTests.cs
@@ -213,5 +213,41 @@ public void all_progress_with_resolved()
 
             Assert.Equal(1, reportedCount);
         }
+
+        [Fact]
+        public void sequence_reports_progress()
+        {
+            var promiseA = new Promise();
+            var promiseB = new Promise();
+            var promiseC = Promise.Resolved();
+            var promiseD = new Promise();
+            int currentReport = 0;
+            var expectedProgress = new[] { 0.125f, 0.25f, 0.25f, 0.3125f, 0.375f, 0.4375f, 0.5f, 0.75f, 0.875f, 1f };
+
+            Promise
+                .Sequence(() => promiseA, () => promiseB, () => promiseC, () => promiseD)
+                .Progress(v =>
+                {
+                    Assert.Equal(expectedProgress[currentReport], v);
+                    ++currentReport;
+                })
+                .Done()
+            ;
+
+            promiseA.ReportProgress(0.5f);
+            promiseA.ReportProgress(1f);
+            promiseA.Resolve();
+
+            promiseB.ReportProgress(0.25f);
+            promiseB.ReportProgress(0.5f);
+            promiseB.ReportProgress(0.75f);
+            promiseB.Resolve();
+
+            promiseD.ReportProgress(0.5f);
+            promiseD.ReportProgress(1f);
+            promiseD.Resolve();
+
+            Assert.Equal(expectedProgress.Length, currentReport);
+        }
     }
 }