Handle yarp.ParseResult with errors and warnings

Author: andrykonchin

src/main/java/org/truffleruby/debug/TruffleDebugNodes.java

@@ -292,7 +292,8 @@ protected Object parse(Object code,
             byte[] serialized = yarpSerialize(getLanguage(), source);
 
             var yarpSource = YARPTranslatorDriver.createYARPSource(source, YARPTranslatorDriver.createRubySource(code));
-            var ast = Loader.load(serialized, yarpSource);
+            var parseResult = Loader.load(serialized, yarpSource);
+            var ast = parseResult.getValue();
 
             return createString(fromJavaStringNode, ast.toString(), Encodings.UTF_8);
         }

src/main/java/org/truffleruby/parser/YARPTranslatorDriver.java

@@ -70,6 +70,7 @@
 import org.truffleruby.language.arguments.MissingArgumentBehavior;
 import org.truffleruby.language.arguments.ReadPreArgumentNode;
 import org.truffleruby.language.arguments.RubyArguments;
+import org.truffleruby.language.control.RaiseException;
 import org.truffleruby.language.control.WhileNode;
 import org.truffleruby.language.control.WhileNodeFactory;
 import org.truffleruby.language.library.RubyStringLibrary;
@@ -84,6 +85,7 @@
 import org.truffleruby.shared.Metrics;
 import org.yarp.Loader;
 import org.yarp.Nodes;
+import org.yarp.ParseResult;
 import org.yarp.Parser;
 
 import java.util.ArrayList;
@@ -405,10 +407,52 @@ public static org.yarp.Nodes.Node parseToYARPAST(RubyContext context, RubyLangua
         byte[] serializedBytes = Parser.parseAndSerialize(sourceBytes);
 
         var yarpSource = createYARPSource(sourceBytes, rubySource);
-        return Loader.load(serializedBytes, yarpSource);
-        // YARP end
+        var parseResult = Loader.load(serializedBytes, yarpSource);
+
+        final String filename = rubySource.getSourcePath();
+        final ParseResult.Error[] errors = parseResult.getErrors();
+
+        // collect warnings generated by the parser
+        for (ParseResult.Warning warning : parseResult.getWarnings()) {
+            Nodes.Location location = warning.getLocation();
+            SourceSection section = rubySource.getSource().createSection(location.startOffset, location.length);
+            int lineNumber = RubySource.getStartLineAdjusted(context, section);
+
+            rubyWarnings.warn(filename, lineNumber, warning.getMessage());
+        }
+
+        if (errors.length != 0) {
+            // print warnings immediately
+            // if there is no syntax error they will be printed in runtime
+            if (!rubyWarnings.warnings.isEmpty()) {
+                EmitWarningsNode.printWarnings(context, rubyWarnings);
+            }
+
+            // Handle only the first reported syntax error.
+            // The order of errors should be deterministic,
+            // but it isn't guarantied that the first error is the most specific/relevant to user
+            ParseResult.Error error = errors[0];
 
-        // TODO: handle syntax errors
+            Nodes.Location location = error.getLocation();
+            SourceSection section = rubySource.getSource().createSection(location.startOffset, location.length);
+            String message = context.fileLine(section) + ": " + error.getMessage();
+
+            if (context != null) {
+                int lineNumber = RubySource.getStartLineAdjusted(context, section);
+
+                throw new RaiseException(
+                        context,
+                        context.getCoreExceptions().syntaxErrorAlreadyWithFileLine(
+                                message,
+                                null,
+                                rubySource.getSource().createSection(lineNumber)));
+            } else {
+                throw new UnsupportedOperationException(message);
+            }
+        }
+
+        return parseResult.getValue();
+        // YARP end
 
         //        RubyParser parser = new RubyParser(lexerSource, rubyWarnings);
         //        TruffleSafepoint.poll(DummyNode.INSTANCE); // RubyParser <clinit> takes a while