From d8dfaf29e6bec228f299cb8b8d14c6cd7726418d Mon Sep 17 00:00:00 2001
From: Mark Bates <mark@markbates.com>
Date: Sat, 15 Jun 2019 18:29:19 -0400
Subject: [PATCH] recently used skill

---
 dir.go      | 56 ++++++++++++++++++++++------------
 info_map.go | 87 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 module.go   | 10 +++---
 3 files changed, 128 insertions(+), 25 deletions(-)
 create mode 100644 info_map.go

diff --git a/dir.go b/dir.go
index 5578363..777af73 100644
--- a/dir.go
+++ b/dir.go
@@ -2,43 +2,59 @@ package here
 
 import (
 	"encoding/json"
+	"fmt"
 	"os"
 	"path/filepath"
 )
 
+var dirCache = &infoMap{}
+
 // Dir attempts to gather info for the requested directory.
 func Dir(p string) (Info, error) {
-	i := newInfo()
+	var err error
+	i, ok := dirCache.LoadOr(p, func(m *infoMap) (Info, bool) {
+		i := newInfo()
 
-	fi, err := os.Stat(p)
-	if err != nil {
-		return i, err
-	}
+		fi, err := os.Stat(p)
+		if err != nil {
+			return i, false
+		}
 
-	if !fi.IsDir() {
-		p = filepath.Dir(p)
-	}
+		if !fi.IsDir() {
+			p = filepath.Dir(p)
+		}
 
-	pwd, err := os.Getwd()
-	if err != nil {
-		return i, err
-	}
+		pwd, err := os.Getwd()
+		if err != nil {
+			return i, false
+		}
+
+		defer os.Chdir(pwd)
+
+		os.Chdir(p)
+
+		b, err := run("go", "list", "-json")
+		if err != nil {
+			return i, false
+		}
 
-	defer os.Chdir(pwd)
+		if err := json.Unmarshal(b, &i); err != nil {
+			return i, false
+		}
 
-	os.Chdir(p)
+		if err := setEnv(&i); err != nil {
+			return i, false
+		}
+		return i, true
+	})
 
-	b, err := run("go", "list", "-json")
 	if err != nil {
 		return i, err
 	}
 
-	if err := json.Unmarshal(b, &i); err != nil {
-		return i, err
+	if !ok {
+		return i, fmt.Errorf("an error occurred %s", p)
 	}
 
-	if err := setEnv(&i); err != nil {
-		return i, err
-	}
 	return i, nil
 }
diff --git a/info_map.go b/info_map.go
new file mode 100644
index 0000000..b3f2ef6
--- /dev/null
+++ b/info_map.go
@@ -0,0 +1,87 @@
+// Code generated by github.com/gobuffalo/mapgen. DO NOT EDIT.
+
+package here
+
+import (
+	"sort"
+	"sync"
+)
+
+// infoMap wraps sync.Map and uses the following types:
+// key:   string
+// value: Info
+type infoMap struct {
+	data sync.Map
+}
+
+// Delete the key from the map
+func (m *infoMap) Delete(key string) {
+	m.data.Delete(key)
+}
+
+// Load the key from the map.
+// Returns Info or bool.
+// A false return indicates either the key was not found
+// or the value is not of type Info
+func (m *infoMap) Load(key string) (Info, bool) {
+	i, ok := m.data.Load(key)
+	if !ok {
+		return Info{}, false
+	}
+	s, ok := i.(Info)
+	return s, ok
+}
+
+// LoadOrStore will return an existing key or
+// store the value if not already in the map
+func (m *infoMap) LoadOrStore(key string, value Info) (Info, bool) {
+	i, _ := m.data.LoadOrStore(key, value)
+	s, ok := i.(Info)
+	return s, ok
+}
+
+// LoadOr will return an existing key or
+// run the function and store the results
+func (m *infoMap) LoadOr(key string, fn func(*infoMap) (Info, bool)) (Info, bool) {
+	i, ok := m.Load(key)
+	if ok {
+		return i, ok
+	}
+	i, ok = fn(m)
+	if ok {
+		m.Store(key, i)
+		return i, ok
+	}
+	return i, false
+}
+
+// Range over the Info values in the map
+func (m *infoMap) Range(f func(key string, value Info) bool) {
+	m.data.Range(func(k, v interface{}) bool {
+		key, ok := k.(string)
+		if !ok {
+			return false
+		}
+		value, ok := v.(Info)
+		if !ok {
+			return false
+		}
+		return f(key, value)
+	})
+}
+
+// Store a Info in the map
+func (m *infoMap) Store(key string, value Info) {
+	m.data.Store(key, value)
+}
+
+// Keys returns a list of keys in the map
+func (m *infoMap) Keys() []string {
+	var keys []string
+	m.Range(func(key string, value Info) bool {
+		keys = append(keys, key)
+		return true
+	})
+	sort.Strings(keys)
+	return keys
+}
diff --git a/module.go b/module.go
index 7e70365..50be1eb 100644
--- a/module.go
+++ b/module.go
@@ -3,11 +3,11 @@ package here
 import "encoding/json"
 
 type Module struct {
-	Path		string	`json:"Path"`
-	Main		bool	`json:"Main"`
-	Dir		string	`json:"Dir"`
-	GoMod		string	`json:"GoMod"`
-	GoVersion	string	`json:"GoVersion"`
+	Path      string `json:"Path"`
+	Main      bool   `json:"Main"`
+	Dir       string `json:"Dir"`
+	GoMod     string `json:"GoMod"`
+	GoVersion string `json:"GoVersion"`
 }
 
 func (i Module) String() string {