replacer api, unit tests, and benchmarks (#354)

* added abstracted replacer api, and both char and regex based implementations

* added test dependencies for jmh and junit

* added unit tests and benchmarks for the replacer implementations

* updated replacers to accept specific closure types, added test to verify malformed placeholder handling

* updated jmh to 1.23, updated junit to 5.6.2

src/main/java/me/clip/placeholderapi/replacer/CharsReplacer.java

@@ -0,0 +1,129 @@
+package me.clip.placeholderapi.replacer;
+
+import me.clip.placeholderapi.PlaceholderHook;
+import org.bukkit.OfflinePlayer;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+
+public final class CharsReplacer implements Replacer
+{
+
+	@NotNull
+	private final Closure closure;
+
+	public CharsReplacer(@NotNull final Closure closure)
+	{
+		this.closure = closure;
+	}
+
+
+	@Override
+	public @NotNull String apply(@NotNull final String text, @Nullable final OfflinePlayer player, @NotNull final Function<String, @Nullable PlaceholderHook> lookup)
+	{
+		final char[]        chars   = text.toCharArray();
+		final StringBuilder builder = new StringBuilder(text.length());
+
+		final StringBuilder identifier = new StringBuilder();
+		final StringBuilder parameters = new StringBuilder();
+
+		for (int i = 0; i < chars.length; i++)
+		{
+			final char l = chars[i];
+
+			if (l == '&' && ++i < chars.length)
+			{
+				final char c = chars[i];
+
+				if (c != '0' && c != '1' && c != '2' && c != '3' && c != '4' && c != '5' && c != '6' && c != '7' && c != '8' && c != '9' && c != 'a' && c != 'b' && c != 'c' && c != 'd' && c != 'e' && c != 'f' && c != 'k' && c != 'l' && c != 'm' && c != 'o' && c != 'r' && c != 'x')
+				{
+					builder.append(l).append(c);
+				}
+				else
+				{
+					builder.append('§').append(c);
+				}
+				continue;
+			}
+
+			if (l != closure.head || i + 1 >= chars.length)
+			{
+				builder.append(l);
+				continue;
+			}
+
+			boolean identified = false;
+			boolean oopsitsbad = false;
+
+			while (++i < chars.length)
+			{
+				final char p = chars[i];
+
+				if (p == closure.tail)
+				{
+					break;
+				}
+
+				if (p == ' ')
+				{
+					oopsitsbad = true;
+					break;
+				}
+
+				if (p == '_' && !identified)
+				{
+					identified = true;
+					continue;
+				}
+
+				if (identified)
+				{
+					parameters.append(p);
+				}
+				else
+				{
+					identifier.append(p);
+				}
+			}
+
+			final String identifierString = identifier.toString();
+			final String parametersString = parameters.toString();
+
+			identifier.setLength(0);
+			parameters.setLength(0);
+
+			if (oopsitsbad)
+			{
+				builder.append(closure.head).append(identifierString);
+
+				if (identified)
+				{
+					builder.append('_').append(parametersString);
+				}
+
+				builder.append(' ');
+				continue;
+			}
+
+			final PlaceholderHook placeholder = lookup.apply(identifierString);
+			if (placeholder == null)
+			{
+				builder.append(closure.head).append(identifierString).append('_').append(parametersString).append(closure.tail);
+				continue;
+			}
+
+			final String replacement = placeholder.onRequest(player, parametersString);
+			if (replacement == null)
+			{
+				builder.append(closure.head).append(identifierString).append('_').append(parametersString).append(closure.tail);
+				continue;
+			}
+
+			builder.append(replacement);
+		}
+
+		return builder.toString();
+	}
+
+}

src/main/java/me/clip/placeholderapi/replacer/RegexReplacer.java

@@ -0,0 +1,55 @@
+package me.clip.placeholderapi.replacer;
+
+import me.clip.placeholderapi.PlaceholderHook;
+import org.bukkit.ChatColor;
+import org.bukkit.OfflinePlayer;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public final class RegexReplacer implements Replacer
+{
+
+	@NotNull
+	private final Pattern pattern;
+
+	public RegexReplacer(@NotNull final Closure closure)
+	{
+		this.pattern = Pattern.compile(String.format("\\%s((?<identifier>[a-zA-Z0-9]+)_)(?<parameters>[^%s%s]+)\\%s", closure.head, closure.head, closure.tail, closure.tail));
+	}
+
+
+	@Override
+	public @NotNull String apply(@NotNull final String text, @Nullable final OfflinePlayer player, @NotNull final Function<String, @Nullable PlaceholderHook> lookup)
+	{
+		final Matcher matcher = pattern.matcher(text);
+		if (!matcher.find())
+		{
+			return text;
+		}
+
+		final StringBuffer builder = new StringBuffer();
+
+		do
+		{
+			final String identifier = matcher.group("identifier");
+			final String parameters = matcher.group("parameters");
+
+			final PlaceholderHook hook = lookup.apply(identifier);
+			if (hook == null)
+			{
+				continue;
+			}
+
+			final String requested = hook.onRequest(player, parameters);
+			matcher.appendReplacement(builder, requested != null ? requested : matcher.group(0));
+		}
+		while (matcher.find());
+
+		return ChatColor.translateAlternateColorCodes('&', matcher.appendTail(builder).toString());
+	}
+
+}

src/main/java/me/clip/placeholderapi/replacer/Replacer.java

@@ -0,0 +1,33 @@
+package me.clip.placeholderapi.replacer;
+
+import me.clip.placeholderapi.PlaceholderHook;
+import org.bukkit.OfflinePlayer;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.function.Function;
+
+public interface Replacer
+{
+
+	@NotNull
+	String apply(@NotNull final String text, @Nullable final OfflinePlayer player, @NotNull final Function<String, @Nullable PlaceholderHook> lookup);
+
+
+	enum Closure
+	{
+		BRACES('{', '}'),
+		BRACKETS('[', ']'),
+		PERCENT('%', '%');
+
+
+		public final char head, tail;
+
+		Closure(final char head, final char tail)
+		{
+			this.head = head;
+			this.tail = tail;
+		}
+	}
+
+}