Better registration username error messages; close #4077

modules/i18n/src/main/I18nKeys.scala

@@ -630,8 +630,9 @@ val `boardSize` = new Translated("boardSize", Site)
 val `pieceSet` = new Translated("pieceSet", Site)
 val `embedInYourWebsite` = new Translated("embedInYourWebsite", Site)
 val `usernameAlreadyUsed` = new Translated("usernameAlreadyUsed", Site)
-val `usernameInvalid` = new Translated("usernameInvalid", Site)
-val `usernameStartNoNumber` = new Translated("usernameStartNoNumber", Site)
+val `usernamePrefixInvalid` = new Translated("usernamePrefixInvalid", Site)
+val `usernameSuffixInvalid` = new Translated("usernameSuffixInvalid", Site)
+val `usernameCharsInvalid` = new Translated("usernameCharsInvalid", Site)
 val `usernameUnacceptable` = new Translated("usernameUnacceptable", Site)
 val `directlySupportLichess` = new Translated("directlySupportLichess", Site)
 val `playChessInStyle` = new Translated("playChessInStyle", Site)

modules/security/src/main/DataForm.scala

@@ -37,8 +37,16 @@ final class DataForm(
       Constraints minLength 2,
       Constraints maxLength 20,
       Constraints.pattern(
-        regex = User.newUsernameRegex,
-        error = "usernameInvalid"
+        regex = User.newUsernamePrefix,
+        error = "usernamePrefixInvalid"
+      ),
+      Constraints.pattern(
+        regex = User.newUsernameSuffix,
+        error = "usernameSuffixInvalid"
+      ),
+      Constraints.pattern(
+        regex = User.newUsernameChars,
+        error = "usernameCharsInvalid"
       )
     ).verifying("usernameUnacceptable", u => !LameName.username(u))
       .verifying("usernameAlreadyUsed", u => !UserRepo.nameExists(u).awaitSeconds(4))

modules/user/src/main/User.scala

@@ -148,9 +148,15 @@ object User {
 
   // what existing usernames are like
   val historicalUsernameRegex = """(?i)[a-z0-9][\w-]*[a-z0-9]""".r
-  // what new usernames should be like
+  // what new usernames should be like -- now split into further parts for clearer error messages
   val newUsernameRegex = """(?i)[a-z][\w-]*[a-z0-9]""".r
 
+  val newUsernamePrefix = """(?i)[a-z].*""".r
+
+  val newUsernameSuffix = """(?i).*[a-z0-9]""".r
+
+  val newUsernameChars = """(?i)[\w-]*""".r
+
   def couldBeUsername(str: User.ID) = historicalUsernameRegex.pattern.matcher(str).matches
 
   def normalize(username: String) = username.toLowerCase

modules/user/src/test/UserTest.scala

@@ -5,7 +5,7 @@ import org.specs2.mutable.Specification
 class UserTest extends Specification {
 
   def canSignup(str: User.ID) =
-    User.newUsernameRegex.pattern.matcher(str).matches
+        User.newUsernamePrefix.pattern.matcher(str).matches && User.newUsernameSuffix.pattern.matcher(str).matches && User.newUsernameChars.pattern.matcher(str).matches
 
   "username regex" in {
     import User.couldBeUsername

translation/source/site.xml

@@ -752,8 +752,9 @@ in %3$s</string>
   <string name="pieceSet">Piece set</string>
   <string name="embedInYourWebsite">Embed in your website</string>
   <string name="usernameAlreadyUsed">This username is already in use, please try another one.</string>
-  <string name="usernameInvalid">Invalid username. Please use only letters, numbers, underscore and dash.</string>
-  <string name="usernameStartNoNumber">The username must not start with a number.</string>
+  <string name="usernamePrefixInvalid">The username must start with a letter.</string>
+  <string name="usernameSuffixInvalid">The username must end with a letter or a number.</string>
+  <string name="usernameCharsInvalid">The username must only contain letters, numbers, underscores, and hyphens.</string>
   <string name="usernameUnacceptable">This username is not acceptable.</string>
   <string name="directlySupportLichess">Directly support Lichess</string>
   <string name="playChessInStyle">Play chess in style</string>