feat(objectionary#3756): add LocationMessage

eo-parser/src/main/java/org/eolang/parser/EoParserErrors.java

@@ -87,6 +87,7 @@ public void syntaxError(
                 )
             );
         }
+        final List<String> msgs = new ArrayList<>(0);
         if (error instanceof NoViableAltException || error instanceof InputMismatchException) {
             final Token token = (Token) symbol;
             final Parser parser = (Parser) recognizer;
@@ -102,49 +103,21 @@ public void syntaxError(
             } else {
                 detailed = "no viable alternative at input";
             }
-            this.errors.add(
-                new ParsingException(
-                    String.format(
-                        "[%d:%d] %s: %s:%n%s",
-                        line,
-                        position,
-                        "error",
-                        detailed,
-                        new UnderlinedMessage(
-                            this.lines.line(line),
-                            position,
-                            Math.max(token.getStopIndex() - token.getStartIndex(), 1)
-                        ).formatted()
-                    ),
-                    error,
-                    line
-                )
+            msgs.add(new LocationMessage(line, position, detailed).formatted());
+            msgs.add(
+                new UnderlinedMessage(
+                    this.lines.line(line),
+                    position,
+                    Math.max(token.getStopIndex() - token.getStartIndex(), 1)
+                ).formatted()
             );
         } else if (Objects.isNull(error)) {
-            this.errors.add(
-                new ParsingException(
-                    String.format(
-                        "[%d:%d] %s: %s",
-                        line,
-                        position,
-                        "error",
-                        msg
-                    ),
-                    line
-                )
-            );
+            msgs.add(new LocationMessage(line, position, msg).formatted());
         } else {
-            this.errors.add(
-                new ParsingException(
-                    String.format(
-                        "[%d:%d] %s: \"%s\"",
-                        line, position, msg, this.lines.line(line)
-                    ),
-                    error,
-                    line
-                )
-            );
+            msgs.add(new LocationMessage(line, position, msg).formatted());
+            msgs.add(this.lines.line(line));
         }
+        this.errors.add(new ParsingException(msg, error, line));
     }
 
     @Override

eo-parser/src/main/java/org/eolang/parser/LocationMessage.java

@@ -0,0 +1,62 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2016-2024 Objectionary.com
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.eolang.parser;
+
+final class LocationMessage {
+
+    /**
+     * The line where the error occurred.
+     */
+    private final int line;
+
+    /**
+     * The position in the line where the error occurred.
+     */
+    private final int position;
+
+    /**
+     * The error message.
+     */
+    private final String message;
+
+    /**
+     * Ctor.
+     * @param line The line where the error occurred.
+     * @param position The position in the line where the error occurred.
+     * @param message The error message.
+     */
+    LocationMessage(final int line, final int position, final String message) {
+        this.line = line;
+        this.position = position;
+        this.message = message;
+    }
+
+    /**
+     * Formats the error message.
+     * @return The formatted error message.
+     */
+    String formatted() {
+        return String.format("[%d:%d] error: \"%s\"", this.line, this.position, this.message);
+    }
+}

eo-parser/src/main/java/org/eolang/parser/ParsingException.java

@@ -23,6 +23,8 @@
  */
 package org.eolang.parser;
 
+import java.util.List;
+
 /**
  * When parsing fails.
  *
@@ -40,6 +42,18 @@ public final class ParsingException extends RuntimeException {
      */
     private final int place;
 
+    /**
+     * Ctor.
+     * @param msgs Messages
+     * @param cause The cause
+     * @param line The place
+     * @since 0.1
+     */
+    ParsingException(final List<String> msgs, final Exception cause, final int line) {
+        this(String.join("\n", msgs), cause, line);
+    }
+
+
     /**
      * Ctor.
      * @param msg Message