From 9a76c648f1225c6349b345ee096dd4278ad47e4e Mon Sep 17 00:00:00 2001
From: vyzo <vyzo@hackzen.org>
Date: Wed, 4 Nov 2020 18:20:25 +0200
Subject: [PATCH] unit test for head change coalescer

---
 chain/store/coalescer_test.go | 68 +++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 chain/store/coalescer_test.go

diff --git a/chain/store/coalescer_test.go b/chain/store/coalescer_test.go
new file mode 100644
index 000000000..cb99690c5
--- /dev/null
+++ b/chain/store/coalescer_test.go
@@ -0,0 +1,68 @@
+package store
+
+import (
+	"testing"
+	"time"
+
+	"github.com/filecoin-project/lotus/chain/types"
+	"github.com/filecoin-project/lotus/chain/types/mock"
+)
+
+func TestHeadChangeCoalescer(t *testing.T) {
+	notif := make(chan headChange, 1)
+	c := NewHeadChangeCoalescer(func(revert, apply []*types.TipSet) error {
+		notif <- headChange{apply: apply, revert: revert}
+		return nil
+	}, 100*time.Millisecond)
+	defer c.Close()
+
+	b0 := mock.MkBlock(nil, 0, 0)
+	root := mock.TipSet(b0)
+	bA := mock.MkBlock(root, 1, 1)
+	tA := mock.TipSet(bA)
+	bB := mock.MkBlock(root, 1, 2)
+	tB := mock.TipSet(bB)
+	tAB := mock.TipSet(bA, bB)
+	bC := mock.MkBlock(root, 1, 3)
+	tABC := mock.TipSet(bA, bB, bC)
+	bD := mock.MkBlock(root, 1, 4)
+	tABCD := mock.TipSet(bA, bB, bC, bD)
+	bE := mock.MkBlock(root, 1, 5)
+	tABCDE := mock.TipSet(bA, bB, bC, bD, bE)
+
+	c.HeadChange(nil, []*types.TipSet{tA})
+	c.HeadChange(nil, []*types.TipSet{tB})
+	c.HeadChange([]*types.TipSet{tA, tB}, []*types.TipSet{tAB})
+	c.HeadChange([]*types.TipSet{tAB}, []*types.TipSet{tABC})
+
+	change := <-notif
+
+	if len(change.revert) != 0 {
+		t.Fatalf("expected empty revert set but got %d elements", len(change.revert))
+	}
+	if len(change.apply) != 1 {
+		t.Fatalf("expected single element apply set but got %d elements", len(change.apply))
+	}
+	if change.apply[0] != tABC {
+		t.Fatalf("expected to apply tABC")
+	}
+
+	c.HeadChange([]*types.TipSet{tABC}, []*types.TipSet{tABCD})
+	c.HeadChange([]*types.TipSet{tABCD}, []*types.TipSet{tABCDE})
+
+	change = <-notif
+
+	if len(change.revert) != 1 {
+		t.Fatalf("expected single element revert set but got %d elements", len(change.revert))
+	}
+	if change.revert[0] != tABC {
+		t.Fatalf("expected to revert tABC")
+	}
+	if len(change.apply) != 1 {
+		t.Fatalf("expected single element apply set but got %d elements", len(change.apply))
+	}
+	if change.apply[0] != tABCDE {
+		t.Fatalf("expected to revert tABC")
+	}
+
+}