Add more unit tests for spread strategy

Signed-off-by: Victor Vieux <vieux@docker.com>

scheduler/strategy/spread_test.go

@@ -8,6 +8,44 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
+func TestSpreadPlaceDifferentNodeSize(t *testing.T) {
+	s := &SpreadPlacementStrategy{}
+
+	nodes := []*node.Node{
+		createNode(fmt.Sprintf("node-0"), 64, 21),
+		createNode(fmt.Sprintf("node-1"), 128, 42),
+	}
+
+	// add 60 containers
+	for i := 0; i < 60; i++ {
+		config := createConfig(0, 0)
+		node := selectTopNode(t, s, config, nodes)
+		assert.NoError(t, node.AddContainer(createContainer(fmt.Sprintf("c%d", i), config)))
+	}
+
+	assert.Equal(t, len(nodes[0].Containers), 30)
+	assert.Equal(t, len(nodes[1].Containers), 30)
+}
+
+func TestSpreadPlaceDifferentNodeSizeCPUs(t *testing.T) {
+	s := &SpreadPlacementStrategy{}
+
+	nodes := []*node.Node{
+		createNode(fmt.Sprintf("node-0"), 64, 21),
+		createNode(fmt.Sprintf("node-1"), 128, 42),
+	}
+
+	// add 60 containers 1CPU
+	for i := 0; i < 60; i++ {
+		config := createConfig(0, 1)
+		node := selectTopNode(t, s, config, nodes)
+		assert.NoError(t, node.AddContainer(createContainer(fmt.Sprintf("c%d", i), config)))
+	}
+
+	assert.Equal(t, len(nodes[0].Containers), 20)
+	assert.Equal(t, len(nodes[1].Containers), 40)
+}
+
 func TestSpreadPlaceEqualWeight(t *testing.T) {
 	s := &SpreadPlacementStrategy{}