#107 better error message

src/main/java/org/xembly/Directives.java

@@ -102,9 +102,8 @@ public Directives() {
     /**
      * Public ctor.
      * @param text Xembly script
-     * @throws SyntaxException If syntax is broken
      */
-    public Directives(final String text) throws SyntaxException {
+    public Directives(final String text) {
         this(new Verbs(text).directives());
     }
 

src/main/java/org/xembly/Verbs.java

@@ -70,29 +70,43 @@ public Collection<Directive> directives() {
                 new CommonTokenStream(lexer)
             );
         lexer.removeErrorListeners();
-        lexer.addErrorListener(this.errors());
+        lexer.addErrorListener(Verbs.errors());
         parser.removeErrorListeners();
-        parser.addErrorListener(this.errors());
+        parser.addErrorListener(Verbs.errors());
         try {
             return parser.directives().ret;
         } catch (final ParsingException ex) {
-            throw new SyntaxException(this.text, ex);
+            throw new SyntaxException(
+                String.format(
+                    "%s \"%s\" in \"%s\"",
+                    ex.getClass().getCanonicalName(),
+                    ex.getLocalizedMessage(),
+                    this.text
+                ),
+                ex
+            );
         }
     }
 
     /**
      * Errors listener.
      * @return Listener
      */
-    private ANTLRErrorListener errors() {
+    private static ANTLRErrorListener errors() {
         return new BaseErrorListener() {
             // @checkstyle ParameterNumberCheck (10 lines)
             @Override
             public void syntaxError(final Recognizer<?, ?> recognizer,
                 final Object symbol, final int line,
                 final int position, final String msg,
                 final RecognitionException error) {
-                throw new SyntaxException(Verbs.this.text, error);
+                throw new SyntaxException(
+                    String.format(
+                        "\"%s\" at line #%d, position #%d, symbol %s",
+                        msg, line, position, symbol
+                    ),
+                    error
+                );
             }
         };
     }

src/test/java/org/xembly/DirectivesTest.java

@@ -90,9 +90,12 @@ void throwsOnBrokenGrammar() {
 
     @Test
     void throwsOnBrokenXmlContent() {
-        Assertions.assertThrows(
-            SyntaxException.class,
-            () -> new Directives("ADD '\u001b';")
+        MatcherAssert.assertThat(
+            Assertions.assertThrows(
+                SyntaxException.class,
+                () -> new Directives("ADD 't';\nADD '\u001b';")
+            ).getMessage(),
+            Matchers.containsString("ADD")
         );
     }
 

src/test/java/org/xembly/VerbsTest.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2013-2022, xembly.org
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met: 1) Redistributions of source code must retain the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer. 2) Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following
+ * disclaimer in the documentation and/or other materials provided
+ * with the distribution. 3) Neither the name of the xembly.org nor
+ * the names of its contributors may be used to endorse or promote
+ * products derived from this software without specific prior written
+ * permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
+ * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.xembly;
+
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test case for {@link Verbs}.
+ *
+ * @since 0.29
+ */
+final class VerbsTest {
+
+    @Test
+    void throwsOnBrokenSyntax() {
+        MatcherAssert.assertThat(
+            Assertions.assertThrows(
+                SyntaxException.class,
+                () -> new Verbs("ADD 't';\nADD 'x';broken").directives()
+            ).getMessage(),
+            Matchers.containsString("token recognition error at: 'b'")
+        );
+    }
+}