Import code from previous AssetBuilder version

2025-07-04 02:01:51 +00:00 · 2019-09-24 10:45:09 +02:00
parent 5609557516
commit 0d8432d4f7
919 changed files with 154412 additions and 26 deletions
--- a/src/ZoneCodeGenerator/Parsing/Parser.cs
+++ b/src/ZoneCodeGenerator/Parsing/Parser.cs
@ -0,0 +1,85 @@
+using System;
+using ZoneCodeGenerator.Parsing.Testing;
+
+namespace ZoneCodeGenerator.Parsing
+{
+    class Parser<TState> where TState : IParserState<TState>
+    {
+        // Amount of consecutive tokens that are output after a parser error to show the region where the error happened.
+        private const int ParserErrorTokenPeekCount = 3;
+
+        private readonly ILexer lexer;
+        private readonly TState state;
+
+        public Parser(TState state, ILexer lexer)
+        {
+            this.state = state;
+            this.lexer = lexer;
+        }
+
+        public bool Parse()
+        {
+            while (!lexer.IsEndOfStream)
+            {
+                var testSuccessful = false;
+
+                try
+                {
+                    foreach (var test in state.GetTests())
+                    {
+                        switch (test.PerformTest(state, lexer))
+                        {
+                            case TokenTestResult.Match:
+                                lexer.SkipTokens(test.ConsumedTokenCount);
+                                testSuccessful = true;
+                                break;
+                            case TokenTestResult.NoMatch:
+                                break;
+                            default:
+                                throw new ArgumentOutOfRangeException();
+                        }
+
+                        if (testSuccessful)
+                            break;
+                    }
+                }
+                catch (LoadingException e)
+                {
+                    PrintParserError(e);
+                    return false;
+                }
+
+                if (!testSuccessful)
+                {
+                    PrintParserError(new LoadingException("Could not parse expression"));
+                    return false;
+                }
+
+                // Peek for the next token here to be able to determine if the stream is at its end or not
+                lexer.PeekToken();
+            }
+
+            return true;
+        }
+
+        private void PrintParserError(LoadingException e)
+        {
+            Console.WriteLine($"Parsing failed in file '{lexer.CurrentFile}' at line {lexer.CurrentLine}:");
+            
+            Console.WriteLine(e.Message);
+
+            Console.Write("  ");
+
+            var tokenCountToShow = Math.Max(ParserErrorTokenPeekCount, lexer.CachedTokenCount);
+            for (var i = 0; i < tokenCountToShow; i++)
+            {
+                var token = lexer.PeekToken(i);
+                if (string.IsNullOrEmpty(token))
+                    break;
+                Console.Write($"{token} ");
+            }
+            Console.WriteLine();
+            Console.WriteLine();
+        }
+    }
+}