PatternElement Combinations + Conflicts Test (#8138)

* Create PatternConflictsTest.java

* Draft

* Update

* Update PatternParserTest.java

* Revert

* Update PatternParserTest.java

* Update PatternParserTest.java

* Filtering + Exclusions

* PatternElement Usage

* Fix TypePatternElement

* Partial Changes

* Update PatternConflictsTest.java

* Update PatternConflictsTest.java

* Update PatternConflictsTest.java

* Update PatternConflictsTest.java

* Requested Changes

* Pickles Changes

Author: Absolutionism

src/main/java/ch/njol/skript/patterns/ChoicePatternElement.java

@@ -3,7 +3,9 @@
 import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 import java.util.stream.Collectors;
 
 /**
@@ -55,4 +57,12 @@ public String toString() {
 			.map(PatternElement::toFullString)
 			.collect(Collectors.joining("|"));
 	}
+
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		Set<String> combinations = new HashSet<>();
+		patternElements.forEach(patternElement -> combinations.addAll(patternElement.getAllCombinations(clean)));
+		return combinations;
+	}
+
 }

src/main/java/ch/njol/skript/patterns/GroupPatternElement.java

@@ -2,6 +2,8 @@
 
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Set;
+
 /**
  * A {@link PatternElement} that represents a group, for example {@code (test)}.
  */
@@ -34,4 +36,9 @@ public String toString() {
 		return "(" + patternElement + ")";
 	}
 
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		return patternElement.getAllCombinations(clean);
+	}
+
 }

src/main/java/ch/njol/skript/patterns/LiteralPatternElement.java

@@ -2,7 +2,9 @@
 
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashSet;
 import java.util.Locale;
+import java.util.Set;
 
 /**
  * A {@link PatternElement} that contains a literal string to be matched, for example {@code hello world}.
@@ -52,4 +54,9 @@ public String toString() {
 		return new String(literal);
 	}
 
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		return new HashSet<>(Set.of(toString()));
+	}
+
 }

src/main/java/ch/njol/skript/patterns/OptionalPatternElement.java

@@ -2,6 +2,8 @@
 
 import org.jetbrains.annotations.Nullable;
 
+import java.util.Set;
+
 /**
  * A {@link PatternElement} that contains an optional part, for example {@code [hello world]}.
  */
@@ -37,4 +39,11 @@ public String toString() {
 		return "[" + patternElement.toFullString() + "]";
 	}
 
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		Set<String> combinations = patternElement.getAllCombinations(clean);
+		combinations.add("");
+		return combinations;
+	}
+
 }

src/main/java/ch/njol/skript/patterns/ParseTagPatternElement.java

@@ -2,7 +2,9 @@
 
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashSet;
 import java.util.List;
+import java.util.Set;
 
 /**
  * A {@link PatternElement} that applies a parse mark when matched.
@@ -82,4 +84,16 @@ public String toString() {
 		}
 	}
 
+	/**
+	 * {@inheritDoc}
+	 * @param clean Whether the parse mark/tag should be excluded.
+	 */
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		Set<String> combinations = new HashSet<>();
+		if (!clean)
+			combinations.add(toString());
+		return combinations;
+	}
+
 }

src/main/java/ch/njol/skript/patterns/PatternCompiler.java

@@ -45,7 +45,7 @@ public static SkriptPattern compile(String pattern) throws MalformedPatternExcep
 	 * {@link TypePatternElement} should be initiated with.
 	 * @return The first link of the {@link PatternElement} chain
 	 */
-	private static PatternElement compile(String pattern, AtomicInteger expressionOffset) {
+	static PatternElement compile(String pattern, AtomicInteger expressionOffset) {
 		StringBuilder literalBuilder = new StringBuilder();
 		PatternElement first = null;
 

src/main/java/ch/njol/skript/patterns/PatternElement.java

@@ -2,6 +2,9 @@
 
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashSet;
+import java.util.Set;
+
 public abstract class PatternElement {
 
 	@Nullable
@@ -48,4 +51,51 @@ public String toFullString() {
 		return stringBuilder.toString();
 	}
 
+	/**
+	 * Gets the combinations available to this {@link PatternElement}.
+	 * @param clean Whether unnecessary data, determined by each implementation, should be excluded from the combinations.
+	 * @return The combinations.
+	 */
+	public abstract Set<String> getCombinations(boolean clean);
+
+	/**
+	 * Gets all combinations available to this {@link PatternElement} and linked {@link PatternElement}s.
+	 * @param clean Whether unnecessary data, determined by each implementation, should be excluded from the combinations.
+	 * @return The combinations.
+	 */
+	public final Set<String> getAllCombinations(boolean clean) {
+		Set<String> combinations = getCombinations(clean);
+		if (combinations.isEmpty())
+			combinations.add("");
+		PatternElement next = this;
+		while ((next = next.originalNext) != null) {
+			Set<String> newCombinations = new HashSet<>();
+			Set<String> nextCombinations = next.getCombinations(clean);
+			if (nextCombinations.isEmpty())
+				continue;
+			for (String base : combinations) {
+				for (String add : nextCombinations) {
+					newCombinations.add(combineCombination(base, add));
+				}
+			}
+			combinations = newCombinations;
+		}
+		return combinations;
+	}
+
+	/**
+	 * Helper method for appropriately combining two strings together.
+	 * @return The resulting string.
+	 */
+	private static String combineCombination(String first, String second) {
+		if (first.isBlank()) {
+			return second.stripLeading();
+		} else if (second.isEmpty()) {
+			return first.stripTrailing();
+		} else if (first.endsWith(" ") && second.startsWith(" ")) {
+			return first + second.stripLeading();
+		}
+		return first + second;
+	}
+
 }

src/main/java/ch/njol/skript/patterns/RegexPatternElement.java

@@ -5,6 +5,8 @@
 import ch.njol.skript.log.SkriptLogger;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashSet;
+import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -58,4 +60,9 @@ public String toString() {
 		return "<" + pattern + ">";
 	}
 
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		return new HashSet<>(Set.of(toString()));
+	}
+
 }

src/main/java/ch/njol/skript/patterns/TypePatternElement.java

@@ -17,6 +17,9 @@
 import ch.njol.util.NonNullPair;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.HashSet;
+import java.util.Set;
+
 /**
  * A {@link PatternElement} that contains a type to be matched with an expressions, for example {@code %number%}.
  */
@@ -263,4 +266,19 @@ public ExprInfo getExprInfo() {
 		return exprInfo;
 	}
 
+	/**
+	 * {@inheritDoc}
+	 * @param clean Whether this type should be replaced with {@code %*%} if it's not literal.
+	 */
+	@Override
+	public Set<String> getCombinations(boolean clean) {
+		Set<String> combinations = new HashSet<>();
+		if (!clean || flagMask == 2) {
+			combinations.add(toString());
+		} else {
+			combinations.add("%*%");
+		}
+		return combinations;
+	}
+
 }