control unclosed brackets

Author: Eduardo Gulias Davis

src/main/java/emailvalidator4j/parser/DomainPart.java

@@ -53,6 +53,7 @@ public void parse(String domainPart) throws InvalidEmail {
 
     private void doParseDomainPart() throws InvalidEmail {
         int domainPartOpenedParenthesis = 0;
+        boolean openBrackets = false;
         do {
             if (this.lexer.getCurrent().equals(Tokens.SEMICOLON)) {
                 throw new ExpectedATEXT("Expected ATEXT");
@@ -84,7 +85,8 @@ private void doParseDomainPart() throws InvalidEmail {
             this.checkConsecutiveDots();
             this.checkExceptions();
 
-            if (this.lexer.getCurrent().equals(Tokens.OPENBRACKET)) {
+            if (isDomainLiteral(openBrackets)) {
+                openBrackets = true;
                 this.parseLiteralPart();
             }
 
@@ -98,6 +100,14 @@ private void doParseDomainPart() throws InvalidEmail {
         } while (!this.lexer.isAtEnd());
     }
 
+    private boolean isDomainLiteral(boolean openBrackets) throws UnclosedDomainLiteral {
+        if (this.lexer.getCurrent().equals(Tokens.CLOSEBRACKET) && !openBrackets) {
+            throw new UnclosedDomainLiteral("Missing open bracket [");
+        }
+
+        return this.lexer.getCurrent().equals(Tokens.OPENBRACKET);
+    }
+
     private void checkNotAllowedChars(TokenInterface token) throws DomainNotAllowedCharacter {
         if (notAllowedTokens.contains(token)) {
             throw new DomainNotAllowedCharacter(

src/test/java/emailvalidator4j/parser/DomainPartTest.java

@@ -49,7 +49,8 @@ public static Object[][] invalidDomainParts() {
                 {DomainHyphen.class, "@atstart-.com"},
                 {DomainNotAllowedCharacter.class, "@atst\\art.com"},
                 {DomainNotAllowedCharacter.class, "@example\\"},
-                {DomainNotAllowedCharacter.class, "@exa\\mple"}
+                {DomainNotAllowedCharacter.class, "@exa\\mple"},
+                {UnclosedDomainLiteral.class, "@example]"},
         };
     }