Merged CommentScriptMustache with CommentScript. The extra separation made the code a little harder to read without adding much useful organization.

Author: nedtwigg

src/main/java/com/diffplug/freshmark/CommentScript.java

@@ -15,6 +15,10 @@
  */
 package com.diffplug.freshmark;
 
+import java.util.function.Function;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 import javax.script.ScriptEngine;
 import javax.script.ScriptException;
 
@@ -29,26 +33,26 @@
  * A CommentScript has the following form:
  * <pre>
  * {@code
- * [INTRON] sectionName
+ * [COMMENT_START sectionName
  * script
  * script
- * [EXON]
- * lastProgramExecutionResult
- * lastProgramExecutionResult
- * lastProgramExecutionResult
- * [INTRON] /sectionName [EXON]
+ * COMMENT_END]
+ * body
+ * body
+ * body
+ * [COMMENT_START /sectionName COMMENT_END]
  * }
  * </pre>
  * This class is a minimal implementation of a CommentScript.  To create a CommentScript,
  * you must provide:
  * <ul>
- * <li>The intron and exon strings in the constructor.</li>
+ * <li>A {@link Parser} to split the comment text from the body text.</li>
  * <li>{@link #keyToValue} - defines how template keys in the script string are transformed into values</li>
  * <li>{@link #setupScriptEngine} - initializes any functions or variables which should be available to the script</li>
  * </ul>
- * See {@link FreshMark} for a sample implementation.
+ * @see FreshMark
  */
-public abstract class CommentScript {
+public abstract class CommentScript implements Parser.SectionCompiler {
 	/**
 	 * Creates a CommentScript using the given parser to
 	 * delineate and combine comment blocks.
@@ -61,30 +65,37 @@ protected CommentScript(Parser parser) {
 	final Parser parser;
 
 	/** Compiles a single section/script/input combo into the appropriate output. */
-	final ParserIntronExon.SectionCompiler compiler = new ParserIntronExon.SectionCompiler() {
-		@Override
-		public String compileSection(String section, String script, String input) {
-			return Errors.rethrow().get(() -> {
-				ScriptEngine engine = setupScriptEngine(section);
+	@Override
+	public String compileSection(String section, String script, String input) {
+		return Errors.rethrow().get(() -> {
+			ScriptEngine engine = setupScriptEngine(section);
 
-				// apply the templating engine to the script
-				String templatedProgram = template(section, script);
-				// populate the input data
-				engine.put("input", input);
-				// evaluate the script and get the result
-				engine.eval(templatedProgram);
-				return Check.cast(engine.get("output"), String.class);
-			});
-		}
-	};
+			// apply the templating engine to the script
+			String templatedProgram = template(section, script);
+			// populate the input data
+			engine.put("input", input);
+			// evaluate the script and get the result
+			engine.eval(templatedProgram);
+			return Check.cast(engine.get("output"), String.class);
+		});
+	}
 
 	/** Compiles the given input string. Input must contain only unix newlines, output is guaranteed to be the same. */
 	public String compile(String input) {
-		return parser.compile(input, compiler);
+		return parser.compile(input, this);
 	}
 
-	/** For the given section, perform templating on the given script. */
-	protected abstract String template(String section, String script);
+	/**
+	 * Performs templating on the script before passing it to the {@link ScriptEngine} created by {@link #setupScriptEngine}.
+	 * <p>
+	 * Defaults to mustache-based templating which uses {@link #keyToValue(String, String)} to decode keys.
+	 */
+	protected String template(String section, String script) {
+		return mustacheTemplate(script, key -> keyToValue(section, key));
+	}
+
+	/** For the given section, return the templated value for the given key. */
+	protected abstract String keyToValue(String section, String script);
 
 	/**
 	 * For the given section, setup any built-in functions and variables.
@@ -93,4 +104,22 @@ public String compile(String input) {
 	 * be extracted for you, but you must do everything else.
 	 */
 	protected abstract ScriptEngine setupScriptEngine(String section) throws ScriptException;
+
+	/** Mustache templating. */
+	static String mustacheTemplate(String input, Function<String, String> keyToValue) {
+		Matcher matcher = MUSTACHE_PATTERN.matcher(input);
+		StringBuilder result = new StringBuilder(input.length() * 3 / 2);
+
+		int lastElement = 0;
+		while (matcher.find()) {
+			result.append(matcher.group(1));
+			result.append(keyToValue.apply(matcher.group(2)));
+			lastElement = matcher.end();
+		}
+		result.append(input.substring(lastElement));
+		return result.toString();
+	}
+
+	/** Regex which matches for {@code {{key}}}. */
+	private static final Pattern MUSTACHE_PATTERN = Pattern.compile("(.*?)\\{\\{(.*?)\\}\\}", Pattern.DOTALL);
 }

src/main/java/com/diffplug/freshmark/CommentScriptMustache.java

@@ -31,7 +31,7 @@
 import com.diffplug.jscriptbox.Language;
 
 /** The default implementation. */
-public class FreshMark extends CommentScriptMustache {
+public class FreshMark extends CommentScript {
 	private static final String INTRON = "<!---freshmark";
 	private static final String EXON = "-->";
 

src/main/java/com/diffplug/freshmark/FreshMark.java

@@ -20,12 +20,12 @@
 import org.junit.Assert;
 import org.junit.Test;
 
-public class CommentScriptMustacheTest {
+public class CommentScriptTest {
 	@Test
-	public void testTemplate() {
+	public void testMustacheTemplate() {
 		String before = TestResource.getTestResource("template_before.txt");
 		String after = TestResource.getTestResource("template_after.txt");
-		String afterActual = CommentScriptMustache.mustacheTemplate(before, key -> key.toUpperCase(Locale.US));
+		String afterActual = CommentScript.mustacheTemplate(before, key -> key.toUpperCase(Locale.US));
 		Assert.assertEquals(after, afterActual);
 	}
 }