test: add tests for circle depends

fet.go

@@ -153,10 +153,11 @@ var (
 )
 
 // ImportNode
+// every node will lookup it's prevs
+// so nexts are not necessary
 type ImportNode struct {
 	Value string
 	Prevs []*ImportNode
-	Nexts []*ImportNode
 }
 
 func (importNode *ImportNode) LookupCircle(search *ImportNode, chains []*ImportNode) []string {
@@ -208,7 +209,6 @@ func (imports *Imports) Add(cur string, depend string) []string {
 		node := &ImportNode{
 			Value: cur,
 			Prevs: []*ImportNode{},
-			Nexts: []*ImportNode{},
 		}
 		imports.Nodes[cur] = node
 		curNode = node
@@ -225,14 +225,11 @@ func (imports *Imports) Add(cur string, depend string) []string {
 				// add cur node to the next node's prevs
 				curNode,
 			},
-			Nexts: []*ImportNode{},
 		}
 		imports.Nodes[depend] = node
 		nextNode = node
 	}
-	// add next node to cur node's nexts
-	curNode.Nexts = append(curNode.Nexts, nextNode)
-	// judge if the next depend node appears in prevs chains
+	// judge if the next depend node in prevs chains
 	return curNode.LookupCircle(nextNode, []*ImportNode{})
 }
 

fet_test.go

@@ -77,3 +77,37 @@ func TestCompile(t *testing.T) {
 		}, "smaller")
 	})
 }
+
+func TestImportsDepends(t *testing.T) {
+	var initImports = func() Imports {
+		return Imports{
+			Nodes: map[string]*ImportNode{},
+		}
+	}
+	// A -> A depend itself
+	imports := initImports()
+	assert.True(t, len(imports.Add("A", "A")) > 0)
+	// A -> B   B -> C  C -> A
+	imports = initImports()
+	assert.True(t, len(imports.Add("A", "B")) == 0)
+	assert.True(t, len(imports.Add("B", "C")) == 0)
+	assert.True(t, len(imports.Add("C", "A")) > 0)
+	// A -> B  C -> A  B -> C
+	imports = initImports()
+	assert.True(t, len(imports.Add("A", "B")) == 0)
+	assert.True(t, len(imports.Add("C", "A")) == 0)
+	assert.True(t, len(imports.Add("B", "C")) > 0)
+	// C -> D A -> B  D -> A  B -> C
+	imports = initImports()
+	assert.True(t, len(imports.Add("C", "D")) == 0)
+	assert.True(t, len(imports.Add("A", "B")) == 0)
+	assert.True(t, len(imports.Add("D", "A")) == 0)
+	assert.True(t, len(imports.Add("B", "C")) > 0)
+	// A -> B  A -> C  C -> D  D -> A
+	imports = initImports()
+	assert.True(t, len(imports.Add("A", "B")) == 0)
+	assert.True(t, len(imports.Add("A", "C")) == 0)
+	assert.True(t, len(imports.Add("D", "A")) == 0)
+	assert.True(t, len(imports.Add("C", "D")) > 0)
+
+}