From 29f2af11d90ac5c185d80447840bf58274f3014b Mon Sep 17 00:00:00 2001
From: Matthias Radestock <matthias.radestock@gmail.com>
Date: Mon, 29 May 2017 13:48:31 +0100
Subject: [PATCH] introduce mapKeys helper

---
 report/counters.go    | 22 ++++------------------
 report/map_helpers.go | 19 ++++++++++---------
 report/node_set.go    | 30 +++---------------------------
 3 files changed, 17 insertions(+), 54 deletions(-)

diff --git a/report/counters.go b/report/counters.go
index a110330dd..660c32af4 100644
--- a/report/counters.go
+++ b/report/counters.go
@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"fmt"
 	"reflect"
-	"sort"
 
 	"github.com/ugorji/go/codec"
 	"github.com/weaveworks/ps"
@@ -87,28 +86,15 @@ func (c Counters) Merge(other Counters) Counters {
 	return Counters{output}
 }
 
-// ForEach calls f for each k/v pair of counters. Keys are iterated in
-// lexicographical order.
-func (c Counters) ForEach(f func(key string, val int)) {
-	if c.psMap != nil {
-		keys := c.psMap.Keys()
-		sort.Strings(keys)
-		for _, key := range keys {
-			if val, ok := c.psMap.Lookup(key); ok {
-				f(key, val.(int))
-			}
-		}
-	}
-}
-
 // String serializes Counters into a string.
 func (c Counters) String() string {
 	buf := bytes.NewBufferString("{")
 	prefix := ""
-	c.ForEach(func(k string, v int) {
-		fmt.Fprintf(buf, "%s%s: %d", prefix, k, v)
+	for _, key := range mapKeys(c.psMap) {
+		val, _ := c.psMap.Lookup(key)
+		fmt.Fprintf(buf, "%s%s: %d", prefix, key, val.(int))
 		prefix = ", "
-	})
+	}
 	fmt.Fprintf(buf, "}")
 	return buf.String()
 }
diff --git a/report/map_helpers.go b/report/map_helpers.go
index f42978af4..3d6bc7a05 100644
--- a/report/map_helpers.go
+++ b/report/map_helpers.go
@@ -63,16 +63,8 @@ func mapEqual(m, n ps.Map, equalf func(a, b interface{}) bool) bool {
 
 // very similar to ps.Map.String() but with keys sorted
 func mapToString(m ps.Map) string {
-	keys := []string{}
-	if m != nil {
-		for _, k := range m.Keys() {
-			keys = append(keys, k)
-		}
-		sort.Strings(keys)
-	}
-
 	buf := bytes.NewBufferString("{")
-	for _, key := range keys {
+	for _, key := range mapKeys(m) {
 		val, _ := m.Lookup(key)
 		fmt.Fprintf(buf, "%s: %s,\n", key, val)
 	}
@@ -80,6 +72,15 @@ func mapToString(m ps.Map) string {
 	return buf.String()
 }
 
+func mapKeys(m ps.Map) []string {
+	if m == nil {
+		return nil
+	}
+	keys := m.Keys()
+	sort.Strings(keys)
+	return keys
+}
+
 // constants from https://github.com/ugorji/go/blob/master/codec/helper.go#L207
 const (
 	containerMapKey   = 2
diff --git a/report/node_set.go b/report/node_set.go
index b302488a2..5a749ca18 100644
--- a/report/node_set.go
+++ b/report/node_set.go
@@ -3,7 +3,6 @@ package report
 import (
 	"bytes"
 	"fmt"
-	"sort"
 
 	"github.com/davecgh/go-spew/spew"
 	"github.com/ugorji/go/codec"
@@ -85,16 +84,6 @@ func (n NodeSet) Lookup(key string) (Node, bool) {
 	return Node{}, false
 }
 
-// Keys is a list of all the keys in this set.
-func (n NodeSet) Keys() []string {
-	if n.psMap == nil {
-		return nil
-	}
-	k := n.psMap.Keys()
-	sort.Strings(k)
-	return k
-}
-
 // Size is the number of nodes in the set
 func (n NodeSet) Size() int {
 	if n.psMap == nil {
@@ -106,7 +95,7 @@ func (n NodeSet) Size() int {
 // ForEach executes f for each node in the set. Nodes are traversed in sorted
 // order.
 func (n NodeSet) ForEach(f func(Node)) {
-	for _, key := range n.Keys() {
+	for _, key := range mapKeys(n.psMap) {
 		if val, ok := n.psMap.Lookup(key); ok {
 			f(val.(Node))
 		}
@@ -119,22 +108,9 @@ func (n NodeSet) Copy() NodeSet {
 }
 
 func (n NodeSet) String() string {
-	keys := []string{}
-	if n.psMap == nil {
-		n = EmptyNodeSet
-	}
-	psMap := n.psMap
-	if psMap == nil {
-		psMap = ps.NewMap()
-	}
-	for _, k := range psMap.Keys() {
-		keys = append(keys, k)
-	}
-	sort.Strings(keys)
-
 	buf := bytes.NewBufferString("{")
-	for _, key := range keys {
-		val, _ := psMap.Lookup(key)
+	for _, key := range mapKeys(n.psMap) {
+		val, _ := n.psMap.Lookup(key)
 		fmt.Fprintf(buf, "%s: %s, ", key, spew.Sdump(val))
 	}
 	fmt.Fprintf(buf, "}")