Added TrimWS (whitespace) and ListDomainsByIp

hostess.go

@@ -60,6 +60,10 @@ type Hostfile struct {
 	data  string
 }
 
+func TrimWS(s string) string {
+	return strings.Trim(s, " \n\t")
+}
+
 // NewHostFile creates a new Hostfile object from the specified file.
 func NewHostfile(path string) *Hostfile {
 	return &Hostfile{path, make(map[string]*Hostname), ""}
@@ -102,12 +106,34 @@ func getSortedMapKeys(m map[string][]string) []string {
 		keys[i] = k
 		i += 1
 	}
-	keys = sort.StringSlice(keys)
+	sort.Strings(keys)
 	return keys
 }
 
-// Dump takes the current list of Hostnames in this Hostfile and turns it into
-// a string suitable for use as an /etc/hosts file.
+func (h *Hostfile) ListDomainsByIp(ip string) []string {
+	names := make([]string, 0)
+	for _, v := range h.Hosts {
+		if v.Ip == ip {
+			names = append(names, v.Domain)
+		}
+	}
+	sort.Strings(names)
+
+	// Magic for localhost only, to make sure it's the first domain on its line
+	if ip == "127.0.0.1" {
+		for k, v := range names {
+			if v == "localhost" {
+				names = append(names[:k], names[k+1:]...)
+			}
+		}
+		names = append([]string{"localhost"}, names...)
+	}
+
+	return names
+}
+
+// Format takes the current list of Hostnames in this Hostfile and turns it
+// into a string suitable for use as an /etc/hosts file.
 // Sorting uses the following logic:
 // 1. List is sorted by IP address
 // 2. Commented items are left in place

hostess_test.go

@@ -115,11 +115,14 @@ func TestFormatHostname(t *testing.T) {
 }
 
 func TestFormatHostfile(t *testing.T) {
-	// t.Skip("Not implemented")
+	// The sort order here is a bit weird.
+	// 1. We want localhost entries at the top
+	// 2. The rest are sorted by IP as STRINGS, not numeric values, so 10
+	//    precedes 8
 	const expected = `127.0.0.1 localhost devsite
 127.0.1.1 ip-10-37-12-18
-# 8.8.8.8 google.com
-10.37.12.18 devsite.com m.devsite.com`
+10.37.12.18 devsite.com m.devsite.com
+# 8.8.8.8 google.com`
 
 	hostfile := NewHostfile("./hosts")
 	hostfile.Add(Hostname{"localhost", "127.0.0.1", true})
@@ -128,7 +131,40 @@ func TestFormatHostfile(t *testing.T) {
 	hostfile.Add(Hostname{"google.com", "8.8.8.8", false})
 	hostfile.Add(Hostname{"devsite.com", "10.37.12.18", true})
 	hostfile.Add(Hostname{"m.devsite.com", "10.37.12.18", true})
-	if hostfile.Format() != expected {
-		t.Errorf(asserts, expected, hostfile.Format())
+	f := hostfile.Format()
+	if f != expected {
+		t.Errorf(asserts, expected, f)
+	}
+}
+
+func TestTrimWS(t *testing.T) {
+	const expected = `  candy
+
+	`
+	got := TrimWS(expected)
+	if got != "candy" {
+		t.Errorf(asserts, expected, got)
+	}
+}
+
+func TestListDomainsByIp(t *testing.T) {
+	hostfile := NewHostfile("./hosts")
+	hostfile.Add(Hostname{"devsite.com", "10.37.12.18", true})
+	hostfile.Add(Hostname{"m.devsite.com", "10.37.12.18", true})
+	hostfile.Add(Hostname{"google.com", "8.8.8.8", false})
+
+	names := hostfile.ListDomainsByIp("10.37.12.18")
+	if !(names[0] == "devsite.com" && names[1] == "m.devsite.com") {
+		t.Errorf("Expected devsite.com and m.devsite.com. Got %s", names)
+	}
+
+	hostfile2 := NewHostfile("./hosts")
+	hostfile2.Add(Hostname{"localhost", "127.0.0.1", true})
+	hostfile2.Add(Hostname{"ip-10-37-12-18", "127.0.1.1", true})
+	hostfile2.Add(Hostname{"devsite", "127.0.0.1", true})
+
+	names2 := hostfile2.ListDomainsByIp("127.0.0.1")
+	if !(names2[0] == "localhost" && names2[1] == "devsite") {
+		t.Errorf("Expected localhost and devsite. Got %s", names2)
 	}
 }