add first exiting test

server/handler/handler_admin_utils.go

@@ -1,42 +1,10 @@
 package handler
 
-import "fmt"
-
-func validateUsername(username string) error {
-	if username == "" {
-		return fmt.Errorf("please enter the username")
-	}
-	return nil
-}
-
-func validatePasswords(pOne, pTwo string) error {
-	if pOne == "" || pTwo == "" {
-		return fmt.Errorf("please enter the password twice")
-	}
-	if !(pOne == pTwo) {
-		return fmt.Errorf("the two passwords entered were not the same")
-	}
-	return nil
-}
-
-func validateAPIKey(apiKey, secret string) error {
-	if apiKey == "" || secret == "" {
-		return fmt.Errorf("please enter both the api key and secret")
-	}
-	return nil
-}
-
 func firstExisting(or string, strings ...string) string {
-	current := ""
 	for _, s := range strings {
-		if s == "" {
-			continue
+		if s != "" {
+			return s
 		}
-		current = s
-		break
 	}
-	if current == "" {
-		return or
-	}
-	return current
+	return or
 }

server/handler/handler_admin_utils_test.go

@@ -0,0 +1,37 @@
+package handler
+
+import (
+	"testing"
+)
+
+func TestFirstExisting(t *testing.T) {
+	cases := []struct {
+		name   string
+		values []string
+		or     string
+		exp    string
+	}{
+		{"none present",
+			[]string{"one", "two", "three"}, "default",
+			"one"},
+		{"first missing",
+			[]string{"", "two", "three"}, "default",
+			"two"},
+		{"middle missing",
+			[]string{"", "two", ""}, "default",
+			"two"},
+		{"all missing",
+			[]string{"", "", ""}, "default",
+			"default"},
+	}
+	for _, tc := range cases {
+		tc := tc // capture range variable?
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			actu := firstExisting(tc.or, tc.values...)
+			if actu != tc.exp {
+				t.Errorf("expected %q, got %q", tc.exp, actu)
+			}
+		})
+	}
+}

server/handler/handler_admin_validate.go

@@ -0,0 +1,27 @@
+package handler
+
+import "fmt"
+
+func validateUsername(username string) error {
+	if username == "" {
+		return fmt.Errorf("please enter the username")
+	}
+	return nil
+}
+
+func validatePasswords(pOne, pTwo string) error {
+	if pOne == "" || pTwo == "" {
+		return fmt.Errorf("please enter the password twice")
+	}
+	if !(pOne == pTwo) {
+		return fmt.Errorf("the two passwords entered were not the same")
+	}
+	return nil
+}
+
+func validateAPIKey(apiKey, secret string) error {
+	if apiKey == "" || secret == "" {
+		return fmt.Errorf("please enter both the api key and secret")
+	}
+	return nil
+}