Documentation annotations improvements (Prototype). (#7470)

* Add example annotation.

* Support new annotation in documentation generators.

* Update src/main/java/ch/njol/skript/doc/Example.java

src/main/java/ch/njol/skript/doc/Documentation.java

@@ -286,7 +286,12 @@ private static void insertSyntaxElement(final PrintWriter pw, final SyntaxElemen
 		Class<?> elementClass = info.getElementClass();
 		if (elementClass.getAnnotation(NoDoc.class) != null)
 			return;
-		if (elementClass.getAnnotation(Name.class) == null || elementClass.getAnnotation(Description.class) == null || elementClass.getAnnotation(Examples.class) == null || elementClass.getAnnotation(Since.class) == null) {
+		if (elementClass.getAnnotation(Name.class) == null
+			|| elementClass.getAnnotation(Description.class) == null
+			|| (!elementClass.isAnnotationPresent(Examples.class)
+			&& !elementClass.isAnnotationPresent(Example.class)
+			&& !elementClass.isAnnotationPresent(Example.Examples.class))
+			|| elementClass.getAnnotation(Since.class) == null) {
 			Skript.warning("" + elementClass.getSimpleName() + " is missing information");
 			return;
 		}

src/main/java/ch/njol/skript/doc/Example.java

@@ -0,0 +1,50 @@
+package ch.njol.skript.doc;
+
+import java.lang.annotation.*;
+
+/**
+ * An example to be used in documentation for the annotated element.
+ * Multiple example annotations can be stacked on a single syntax element.
+ * <p>
+ * Each annotation should include a single example.
+ * This can be used instead of the existing {@link ch.njol.skript.doc.Examples} annotation.
+ * <p>
+ * <b>Multi-line examples</b> should use multi-line strings.
+ * Note that whitespace and quotes do not need to be escaped in this mode.
+ * The indentation will start from the least-indented line (and most IDEs provide a guideline to show this).
+ * <pre>{@code
+ * @Example("set player's health to 1")
+ * @Example("""
+ * 		if player's health is greater than 10:
+ * 			send "Wow you're really healthy!"
+ * 		""")
+ * @Example("""
+ * 		# sets the player's health to 1
+ * 		set player's health to 1""")
+ * public class MyExpression extends ... {
+ * }
+ * }</pre>
+ */
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+@Repeatable(Example.Examples.class)
+@Documented
+public @interface Example {
+
+	String value();
+
+	boolean inTrigger() default true; // todo needed?
+
+	/**
+	 * The internal container annotation for multiple examples.
+	 */
+	@Target(ElementType.TYPE)
+	@Retention(RetentionPolicy.RUNTIME)
+	@Documented
+	@interface Examples {
+
+		Example[] value();
+
+	}
+
+}

src/main/java/ch/njol/skript/doc/HTMLGenerator.java

@@ -20,6 +20,7 @@
 import org.bukkit.event.Cancellable;
 import org.bukkit.event.Event;
 import org.bukkit.event.block.BlockCanBuildEvent;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.skriptlang.skript.lang.entry.EntryData;
 import org.skriptlang.skript.lang.entry.EntryValidator;
@@ -442,10 +443,7 @@ private String generateAnnotated(String descTemp, SyntaxElementInfo<?> info, @Nu
 			.replace("\\", "\\\\").replace("\"", "\\\"").replace("\t", "    "));
 
 		// Examples
-		Examples examples = c.getAnnotation(Examples.class);
-		desc = desc.replace("${element.examples}", Joiner.on("<br>").join(getDefaultIfNullOrEmpty((examples != null ? Documentation.escapeHTML(examples.value()) : null), "Missing examples.")));
-		desc = desc.replace("${element.examples-safe}", Joiner.on("<br>").join(getDefaultIfNullOrEmpty((examples != null ? Documentation.escapeHTML(examples.value()) : null), "Missing examples."))
-			.replace("\\", "\\\\").replace("\"", "\\\"").replace("\t", "    "));
+		desc = extractExamples(desc, c);
 
 		// Documentation ID
 		desc = desc.replace("${element.id}", DocumentationIdProvider.getId(info));
@@ -546,6 +544,29 @@ private String generateAnnotated(String descTemp, SyntaxElementInfo<?> info, @Nu
 		return desc;
 	}
 
+	private @NotNull String extractExamples(String desc, Class<?> syntax) {
+		if (syntax.isAnnotationPresent(Example.class)) {
+			Example examples = syntax.getAnnotation(Example.class);
+			return this.addExamples(desc, examples.value());
+		} else if (syntax.isAnnotationPresent(Example.Examples.class)) {
+			Example.Examples examples = syntax.getAnnotation(Example.Examples.class);
+			return this.addExamples(desc, Arrays.stream(examples.value())
+				.map(Example::value).toArray(String[]::new));
+		} else if (syntax.isAnnotationPresent(Examples.class)) {
+			Examples examples = syntax.getAnnotation(Examples.class);
+			return this.addExamples(desc, examples.value());
+		} else {
+			return this.addExamples(desc, (String[]) null);
+		}
+	}
+
+	private @NotNull String addExamples(String desc, String @Nullable ... examples) {
+		desc = desc.replace("${element.examples}", Joiner.on("<br>").join(getDefaultIfNullOrEmpty((examples != null ? Documentation.escapeHTML(examples) : null), "Missing examples.")));
+		desc = desc.replace("${element.examples-safe}", Joiner.on("<br>").join(getDefaultIfNullOrEmpty((examples != null ? Documentation.escapeHTML(examples) : null), "Missing examples."))
+			.replace("\\", "\\\\").replace("\"", "\\\"").replace("\t", "    "));
+		return desc;
+	}
+
 	private String generateEvent(String descTemp, SkriptEventInfo<?> info, @Nullable String page) {
 		Class<?> c = info.getElementClass();
 		String desc;

src/main/java/ch/njol/skript/doc/JSONGenerator.java

@@ -13,6 +13,7 @@
 import com.google.gson.JsonArray;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
+import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.skriptlang.skript.lang.structure.Structure;
 import org.skriptlang.skript.lang.structure.StructureInfo;
@@ -21,6 +22,7 @@
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.util.Arrays;
 import java.util.Iterator;
 import java.util.Objects;
 import java.util.stream.Stream;
@@ -39,7 +41,7 @@ public JSONGenerator(File templateDir, File outputDir) {
 	 * @param strings the String array to convert
 	 * @return the JsonArray containing the Strings
 	 */
-	private static @Nullable JsonArray convertToJsonArray(String @Nullable [] strings) {
+	private static @Nullable JsonArray convertToJsonArray(String @Nullable ... strings) {
 		if (strings == null)
 			return null;
 		JsonArray jsonArray = new JsonArray();
@@ -73,9 +75,18 @@ public JSONGenerator(File templateDir, File outputDir) {
 			syntaxJsonObject.add("description", new JsonArray());
 		}
 
-		Examples examplesAnnotation = syntaxClass.getAnnotation(Examples.class);
-		if (examplesAnnotation != null) {
+		if (syntaxClass.isAnnotationPresent(Examples.class)) {
+			@NotNull Examples examplesAnnotation = syntaxClass.getAnnotation(Examples.class);
 			syntaxJsonObject.add("examples", convertToJsonArray(examplesAnnotation.value()));
+		} else if (syntaxClass.isAnnotationPresent(Example.Examples.class)) {
+			// If there are multiple examples, they get containerised
+			@NotNull Example.Examples examplesAnnotation = syntaxClass.getAnnotation(Example.Examples.class);
+			syntaxJsonObject.add("examples", convertToJsonArray(Arrays.stream(examplesAnnotation.value())
+				.map(Example::value).toArray(String[]::new)));
+		} else if (syntaxClass.isAnnotationPresent(Example.class)) {
+			// If the user adds just one example, it isn't containerised
+			@NotNull Example example = syntaxClass.getAnnotation(Example.class);
+			syntaxJsonObject.add("examples", convertToJsonArray(example.value()));
 		} else {
 			syntaxJsonObject.add("examples", new JsonArray());
 		}