Parse elseif

Parser.Tests/MParserShould.cs

@@ -449,6 +449,21 @@ namespace Parser.Tests
             Assert.IsInstanceOf<TryCatchStatementNode>(actual);
             Assert.AreEqual(text, actual.FullText);
         }
-        
+
+        [Test]
+        public void ParseElseif()
+        {
+            var text = @"if a == 1
+            f()
+            elseif a == 2
+            g()
+            elseif a == 3
+            h()
+            end";
+            var sut = CreateParser(text);
+            var actual = sut.ParseStatement();
+            Assert.IsInstanceOf<IfStatementNode>(actual);
+            Assert.AreEqual(text, actual.FullText);
+        }
     }
 }

Parser/MParser.cs

@@ -811,6 +811,21 @@ namespace Parser
                 elseKeyword = Factory.Token(EatToken());
                 elseBody = ParseStatements();
             }
+            if (CurrentToken.Kind == TokenKind.Identifier
+                && CurrentToken.PureToken.LiteralText == "elseif")
+            {
+                elseKeyword = null;
+                var ifStatement = ParseIfStatement();
+                elseBody = Factory.StatementList(new List<SyntaxNode> { ifStatement });
+                return Factory.IfStatement(
+                    ifKeyword,
+                    condition,
+                    body,
+                    null,
+                    elseBody,
+                    null,
+                    commas);
+            }
 
             var endKeyword = Factory.Token(EatIdentifier("end"));
             return Factory.IfStatement(
@@ -903,6 +918,10 @@ namespace Parser
                 {
                     return null;
                 }
+                else if (CurrentToken.PureToken.LiteralText == "elseif")
+                {
+                    return null;
+                }
                 else if (CurrentToken.PureToken.LiteralText == "end")
                 {
                     return null;

Parser/SyntaxFactory.cs

@@ -483,10 +483,18 @@ namespace Parser
             if (elseKeyword != null)
             {
                 children.Add(elseKeyword);
+            }
+
+            if (elseBody != null)
+            {
                 children.Add(elseBody);
             }
 
-            children.Add(endKeyword);
+            if (endKeyword != null)
+            {
+                children.Add(endKeyword);
+            }
+
             var result = new IfStatementNode(
                 children,
                 ifKeyword,