Add methods Reader.getSource and Reader.getSourceLines (#1264)

* Add methods Reader.getSource and Reader.getSourceLines

* Fix codenarc issue

* Clarify comments

CHANGELOG.adoc

@@ -27,6 +27,7 @@ Improvement::
 * Remove deprecated methods from ast package (#1204) (@abelsromero)
 * Add Automatic-Module-Name manifest entry to core, api, and cli for reserving stable JPMS module names (#1240) (@leadpony)
 * Remove Java 'requires open access' module warning in modern Java versions (#1246)
+* Add Reader.getSource() and Reader.getSourceLines() (#1262)
 
 Bug Fixes::
 

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

@@ -72,6 +72,18 @@ public interface Reader {
      */
     List<String> getLines();
 
+    /**
+     * Returns the source lines for this Reader joined as a String
+     * @return The source lines for this Reader joined as a String
+     */
+    String getSource();
+
+    /**
+     * Get the document source as a List of Strings.
+     * @return the document source as a List of Strings.
+     */
+    List<String> getSourceLines();
+
     /**
      * Push the String line onto the beginning of the Array of source data.
      * <p>

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

@@ -70,6 +70,16 @@ public List<String> getLines() {
         return getList("lines", String.class);
     }
 
+    @Override
+    public String getSource() {
+        return getString("source");
+    }
+
+    @Override
+    public List<String> getSourceLines() {
+        return getList("source_lines", String.class);
+    }
+
     @Override
     public void restoreLine(String line) {
         getRubyProperty("unshift_line", line);

asciidoctorj-core/src/test/groovy/org/asciidoctor/extension/WhenAPreprocessorIsRegistered.groovy

@@ -175,4 +175,27 @@ $secondLine"""
         preprocessorCalled.get()
     }
 
+    def 'should be able to get source and source lines'() {
+        given:
+
+        String source = ''
+        List<String> sourceLines = []
+
+        asciidoctor.javaExtensionRegistry().preprocessor(new Preprocessor() {
+            @Override
+            Reader process(Document doc, PreprocessorReader reader) {
+                source = reader.source
+                sourceLines = reader.sourceLines
+                reader
+            }
+        })
+
+        when:
+        asciidoctor.convert(document, emptyOptions())
+
+        then:
+        source == document
+        sourceLines == [firstLine, secondLine]
+    }
+
 }