Add a test with an AsciidoctorJ implementation of the FrontMatterPrep…

…rocessor.

Add method Reader.getLines

asciidoctorj-api/src/main/java/org/asciidoctor/extension/Reader.java

@@ -76,8 +76,18 @@ public interface Reader {
     */
     String readLine();
 
+    /**
+     * @return A copy of the String List of lines remaining in this Reader
+     * @deprecated Use {@link #getLines()}
+     */
+    @Deprecated
     List<String> lines();
 
+    /**
+     * @return A copy of the String List of lines remaining in this Reader
+     */
+    List<String> getLines();
+
     /**
      * Push the String line onto the beginning of the Array of source data.
      *
@@ -107,7 +117,8 @@ public interface Reader {
      * already marked as processed, but does not consume them.
      *
      * @param lineCount The Integer number of lines to peek.
-     * @return
+     * @return A String List of the next multiple lines of source data, or an empty list
+     * if there are no more lines in this Reader.
      */
     List<String> peekLines(int lineCount);
 

asciidoctorj-core/build.gradle

@@ -33,6 +33,7 @@ dependencies {
   testImplementation "com.google.guava:guava:$guavaVersion"
   testImplementation "org.jsoup:jsoup:$jsoupVersion"
   testImplementation "io.netty:netty-all:$nettyVersion"
+  testImplementation "org.assertj:assertj-core:$assertjVersion"
   testImplementation project(path: ':asciidoctorj-arquillian-extension')
   compileOnly "org.osgi:osgi.annotation:$osgiVersion"
 }

asciidoctorj-core/src/main/java/org/asciidoctor/jruby/extension/internal/ReaderImpl.java

@@ -76,6 +76,11 @@ public List<String> lines() {
         return getList("lines", String.class);
     }
 
+    @Override
+    public List<String> getLines() {
+        return getList("lines", String.class);
+    }
+
     @Override
     public void restoreLine(String line) {
         getRubyProperty("unshift_line", line);

asciidoctorj-core/src/test/java/org/asciidoctor/extension/FrontMatterPreprocessor.java

@@ -0,0 +1,32 @@
+package org.asciidoctor.extension;
+
+import org.asciidoctor.ast.Document;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class FrontMatterPreprocessor extends Preprocessor {
+
+    @Override
+    public void process(Document document, PreprocessorReader reader) {
+        List<String> lines = reader.getLines();
+        if (lines.isEmpty()) {
+            return;
+        }
+        List<String> frontMatter = new ArrayList<>();
+        if ("---".equals(lines.get(0).trim())) {
+            lines.remove(0);
+            while (!lines.isEmpty() && !"---".equals(lines.get(0).trim())) {
+                frontMatter.add(lines.remove(0));
+            }
+
+            if (!lines.isEmpty() && "---".equals(lines.get(0).trim())) {
+                lines.remove(0);
+                document.setAttribute("front-matter", frontMatter, true);
+                for (int i = 0; i < frontMatter.size() + 2; i++) {
+                    reader.advance();
+                }
+            }
+        }
+    }
+}

asciidoctorj-core/src/test/java/org/asciidoctor/extension/FrontMatterPreprocessorTest.java

@@ -0,0 +1,66 @@
+package org.asciidoctor.extension;
+
+import org.asciidoctor.Asciidoctor;
+import org.asciidoctor.Options;
+import org.asciidoctor.ast.Document;
+import org.jboss.arquillian.junit.Arquillian;
+import org.jboss.arquillian.test.api.ArquillianResource;
+import org.jsoup.Jsoup;
+import org.jsoup.nodes.Element;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.util.Arrays;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(Arquillian.class)
+public class FrontMatterPreprocessorTest {
+
+    @ArquillianResource
+    private Asciidoctor asciidoctor;
+
+    @Test
+    public void shouldRemoveFrontMatter() {
+        // Given: the FrontMatterPreprocessor
+        asciidoctor.javaExtensionRegistry().preprocessor(FrontMatterPreprocessor.class);
+
+        // And a document with a front matter
+        String document = "---\n" +
+                "layout: info\n" +
+                "permalink: /sample/\n" +
+                "---\n" +
+                "= Sample Page\n" +
+                ":url-asciidoctor: http://asciidoctor.org\n" +
+                "\n" +
+                "This is a sample page composed in AsciiDoc.\n" +
+                "Jekyll converts it to HTML using {url-asciidoctor}[Asciidoctor].\n" +
+                "\n" +
+                "[source,ruby]\n" +
+                "puts \"Hello, World!\"";
+
+        // If I parse the document
+        Document ast = asciidoctor.load(document, Options.builder()
+                .headerFooter(true)
+                .toFile(false)
+                .build());
+
+        // Then: the preprocessor has set the attribute
+        assertThat(ast.getAttribute("front-matter")).isEqualTo(Arrays.asList(
+                "layout: info",
+                "permalink: /sample/"
+        ));
+
+        // And: the processor has removed the front-matter from the converted document
+        String html = ast.convert();
+        assertThat(html).doesNotContain("permalink");
+        assertThat(html).doesNotContain("layout");
+        org.jsoup.nodes.Document htmlTree = Jsoup.parse(html);
+        Element body = htmlTree.body();
+        assertThat(body.getElementsByTag("h1").first().text())
+                .isEqualTo("Sample Page");
+
+        assertThat(body.getElementsByTag("p").first().text())
+                .startsWith("This is a sample page");
+    }
+}

build.gradle

@@ -72,7 +72,7 @@ ext {
   jrubyVersion = '9.3.4.0'
   jsoupVersion = '1.14.3'
   junitVersion = '4.13.2'
-  assertjVersion = '3.19.0'
+  assertjVersion = '3.22.0'
   nettyVersion = '4.1.58.Final'
   saxonVersion = '9.9.0-2'
   xmlMatchersVersion = '1.0-RC1'