Antlr4.AntlrTool.SortGrammarByTokenVocab C# (CSharp) Method

        public virtual IList<GrammarRootAST> SortGrammarByTokenVocab(IList<string> fileNames)
        {
            //System.Console.WriteLine(fileNames);
            Graph<string> g = new Graph<string>();
            IList<GrammarRootAST> roots = new List<GrammarRootAST>();
            foreach (string fileName in fileNames)
            {
                GrammarAST t = ParseGrammar(fileName);
                if (t == null || t is GrammarASTErrorNode)
                    continue; // came back as error node
                if (((GrammarRootAST)t).hasErrors)
                    continue;
                GrammarRootAST root = (GrammarRootAST)t;
                roots.Add(root);
                root.fileName = fileName;
                string grammarName = root.GetChild(0).Text;

                GrammarAST tokenVocabNode = FindOptionValueAST(root, "tokenVocab");
                // Make grammars depend on any tokenVocab options
                if (tokenVocabNode != null)
                {
                    string vocabName = tokenVocabNode.Text;
                    // Strip quote characters if any
                    int len = vocabName.Length;
                    int firstChar = vocabName[0];
                    int lastChar = vocabName[len - 1];
                    if (len >= 2 && firstChar == '\'' && lastChar == '\'')
                    {
                        vocabName = vocabName.Substring(1, len - 2);
                    }
                    // If the name contains a path delimited by forward slashes,
                    // use only the part after the last slash as the name
                    int lastSlash = vocabName.LastIndexOf('/');
                    if (lastSlash >= 0)
                    {
                        vocabName = vocabName.Substring(lastSlash + 1);
                    }
                    g.AddEdge(grammarName, vocabName);
                }
                // add cycle to graph so we always process a grammar if no error
                // even if no dependency
                g.AddEdge(grammarName, grammarName);
            }

            IList<string> sortedGrammarNames = g.Sort();
            //System.Console.WriteLine("sortedGrammarNames=" + sortedGrammarNames);

            IList<GrammarRootAST> sortedRoots = new List<GrammarRootAST>();
            foreach (string grammarName in sortedGrammarNames)
            {
                foreach (GrammarRootAST root in roots)
                {
                    if (root.GetGrammarName().Equals(grammarName))
                    {
                        sortedRoots.Add(root);
                        break;
                    }
                }
            }

            return sortedRoots;
        }