until stable: pin-dependency, update-vendor, update-bazel, lint-dep

vendor/github.com/xlab/treeprint/treeprint.go

@@ -0,0 +1,215 @@
+// Package treeprint provides a simple ASCII tree composing tool.
+package treeprint
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"reflect"
+)
+
+type Value interface{}
+type MetaValue interface{}
+
+// Tree represents a tree structure with leaf-nodes and branch-nodes.
+type Tree interface {
+	// AddNode adds a new node to a branch.
+	AddNode(v Value) Tree
+	// AddMetaNode adds a new node with meta value provided to a branch.
+	AddMetaNode(meta MetaValue, v Value) Tree
+	// AddBranch adds a new branch node (a level deeper).
+	AddBranch(v Value) Tree
+	// AddMetaBranch adds a new branch node (a level deeper) with meta value provided.
+	AddMetaBranch(meta MetaValue, v Value) Tree
+	// Branch converts a leaf-node to a branch-node,
+	// applying this on a branch-node does no effect.
+	Branch() Tree
+	// FindByMeta finds a node whose meta value matches the provided one by reflect.DeepEqual,
+	// returns nil if not found.
+	FindByMeta(meta MetaValue) Tree
+	// FindByValue finds a node whose value matches the provided one by reflect.DeepEqual,
+	// returns nil if not found.
+	FindByValue(value Value) Tree
+	//  returns the last node of a tree
+	FindLastNode() Tree
+	// String renders the tree or subtree as a string.
+	String() string
+	// Bytes renders the tree or subtree as byteslice.
+	Bytes() []byte
+
+	SetValue(value Value)
+	SetMetaValue(meta MetaValue)
+}
+
+type node struct {
+	Root  *node
+	Meta  MetaValue
+	Value Value
+	Nodes []*node
+}
+
+func (n *node) FindLastNode() Tree {
+	ns := n.Nodes
+	n = ns[len(ns)-1]
+	return n
+}
+
+func (n *node) AddNode(v Value) Tree {
+	n.Nodes = append(n.Nodes, &node{
+		Root:  n,
+		Value: v,
+	})
+	if n.Root != nil {
+		return n.Root
+	}
+	return n
+}
+
+func (n *node) AddMetaNode(meta MetaValue, v Value) Tree {
+	n.Nodes = append(n.Nodes, &node{
+		Root:  n,
+		Meta:  meta,
+		Value: v,
+	})
+	if n.Root != nil {
+		return n.Root
+	}
+	return n
+}
+
+func (n *node) AddBranch(v Value) Tree {
+	branch := &node{
+		Value: v,
+	}
+	n.Nodes = append(n.Nodes, branch)
+	return branch
+}
+
+func (n *node) AddMetaBranch(meta MetaValue, v Value) Tree {
+	branch := &node{
+		Meta:  meta,
+		Value: v,
+	}
+	n.Nodes = append(n.Nodes, branch)
+	return branch
+}
+
+func (n *node) Branch() Tree {
+	n.Root = nil
+	return n
+}
+
+func (n *node) FindByMeta(meta MetaValue) Tree {
+	for _, node := range n.Nodes {
+		if reflect.DeepEqual(node.Meta, meta) {
+			return node
+		}
+		if v := node.FindByMeta(meta); v != nil {
+			return v
+		}
+	}
+	return nil
+}
+
+func (n *node) FindByValue(value Value) Tree {
+	for _, node := range n.Nodes {
+		if reflect.DeepEqual(node.Value, value) {
+			return node
+		}
+		if v := node.FindByMeta(value); v != nil {
+			return v
+		}
+	}
+	return nil
+}
+
+func (n *node) Bytes() []byte {
+	buf := new(bytes.Buffer)
+	level := 0
+	var levelsEnded []int
+	if n.Root == nil {
+		if n.Meta != nil {
+			buf.WriteString(fmt.Sprintf("[%v]  %v", n.Meta, n.Value))
+		} else {
+			buf.WriteString(fmt.Sprintf("%v",n.Value))
+		}
+		buf.WriteByte('\n')
+	} else {
+		edge := EdgeTypeMid
+		if len(n.Nodes) == 0 {
+			edge = EdgeTypeEnd
+			levelsEnded = append(levelsEnded, level)
+		}
+		printValues(buf, 0, levelsEnded, edge, n.Meta, n.Value)
+	}
+	if len(n.Nodes) > 0 {
+		printNodes(buf, level, levelsEnded, n.Nodes)
+	}
+	return buf.Bytes()
+}
+
+func (n *node) String() string {
+	return string(n.Bytes())
+}
+
+func (n *node) SetValue(value Value){
+	n.Value = value
+}
+
+func (n *node) SetMetaValue(meta MetaValue){
+	n.Meta = meta
+}
+
+func printNodes(wr io.Writer,
+	level int, levelsEnded []int, nodes []*node) {
+
+	for i, node := range nodes {
+		edge := EdgeTypeMid
+		if i == len(nodes)-1 {
+			levelsEnded = append(levelsEnded, level)
+			edge = EdgeTypeEnd
+		}
+		printValues(wr, level, levelsEnded, edge, node.Meta, node.Value)
+		if len(node.Nodes) > 0 {
+			printNodes(wr, level+1, levelsEnded, node.Nodes)
+		}
+	}
+}
+
+func printValues(wr io.Writer,
+	level int, levelsEnded []int, edge EdgeType, meta MetaValue, val Value) {
+
+	for i := 0; i < level; i++ {
+		if isEnded(levelsEnded, i) {
+			fmt.Fprint(wr, "    ")
+			continue
+		}
+		fmt.Fprintf(wr, "%s   ", EdgeTypeLink)
+	}
+	if meta != nil {
+		fmt.Fprintf(wr, "%s [%v]  %v\n", edge, meta, val)
+		return
+	}
+	fmt.Fprintf(wr, "%s %v\n", edge, val)
+}
+
+func isEnded(levelsEnded []int, level int) bool {
+	for _, l := range levelsEnded {
+		if l == level {
+			return true
+		}
+	}
+	return false
+}
+
+type EdgeType string
+
+var (
+	EdgeTypeLink  EdgeType = "│"
+	EdgeTypeMid   EdgeType = "├──"
+	EdgeTypeEnd   EdgeType = "└──"
+)
+
+func New() Tree {
+	return &node{Value: "."}
+}