Implement type hint updates for more syntax

Author: APickledWalrus

src/main/java/ch/njol/skript/effects/EffCopy.java

@@ -13,6 +13,7 @@
 import ch.njol.skript.lang.SkriptParser.ParseResult;
 import ch.njol.skript.lang.Variable;
 import ch.njol.skript.registrations.Classes;
+import ch.njol.skript.variables.HintManager;
 import ch.njol.skript.variables.Variables;
 import ch.njol.util.Kleenean;
 import org.bukkit.event.Event;
@@ -64,6 +65,16 @@ public boolean init(Expression<?>[] exprs, int matchedPattern, Kleenean isDelaye
 				return false;
 			}
 		}
+
+		// set type hints for destination(s) if applicable
+		Class<?>[] sourceHints = source.possibleReturnTypes();
+		HintManager hintManager = getParser().getHintManager();
+		for (Variable<?> destination : destinations) {
+			if (HintManager.canUseHints(destination)) {
+				hintManager.set(destination, sourceHints);
+			}
+		}
+
 		return true;
 	}
 

src/main/java/ch/njol/skript/effects/EffTransform.java

@@ -14,6 +14,7 @@
 import ch.njol.skript.lang.SkriptParser.ParseResult;
 import ch.njol.skript.lang.Variable;
 import ch.njol.skript.lang.parser.ParserInstance;
+import ch.njol.skript.variables.HintManager;
 import ch.njol.skript.variables.Variables;
 import ch.njol.util.Kleenean;
 import ch.njol.util.Pair;
@@ -69,19 +70,27 @@ public class EffTransform extends Effect implements InputSource {
 
 	@Override
 	public boolean init(Expression<?>[] expressions, int matchedPattern, Kleenean isDelayed, ParseResult parseResult) {
-		if (expressions[0].isSingle() || !(expressions[0] instanceof Variable)) {
+		if (parseResult.regexes.isEmpty()) {
+			return false;
+		}
+
+		if (expressions[0].isSingle() || !(expressions[0] instanceof Variable<?> variable)) {
 			Skript.error("You can only transform list variables!");
 			return false;
 		}
-		unmappedObjects = (Variable<?>) expressions[0];
-
-		//noinspection DuplicatedCode
-		if (!parseResult.regexes.isEmpty()) {
-			@Nullable String unparsedExpression = parseResult.regexes.get(0).group();
-			assert unparsedExpression != null;
-			mappingExpr = parseExpression(unparsedExpression, getParser(), SkriptParser.ALL_FLAGS);
-			return mappingExpr != null;
+		unmappedObjects = variable;
+
+		String unparsedExpression = parseResult.regexes.get(0).group();
+		mappingExpr = parseExpression(unparsedExpression, getParser(), SkriptParser.ALL_FLAGS);
+		if (mappingExpr == null) {
+			return false;
+		}
+
+		// type hints
+		if (HintManager.canUseHints(variable)) {
+			getParser().getHintManager().set(variable, mappingExpr.possibleReturnTypes());
 		}
+
 		return true;
 	}
 

src/main/java/ch/njol/skript/variables/HintManager.java

@@ -175,8 +175,12 @@ public void set(String variableName, Class<?>... hints) {
 				hintSet.add(hint);
 			}
 		}
-		//noinspection DataFlowIssue - verified by checkState
-		typeHints.peek().put(variableName, hintSet);
+		if (hintSet.isEmpty()) { // treat as delete
+			delete(variableName);
+		} else {
+			//noinspection DataFlowIssue - verified by checkState
+			typeHints.peek().put(variableName, hintSet);
+		}
 	}
 
 	/**
@@ -259,6 +263,9 @@ public void remove(String variableName, Class<?>... hints) {
 			for (Class<?> hint : hints) {
 				hintSet.remove(hint);
 			}
+			if (hintSet.isEmpty()) {
+				delete(variableName);
+			}
 		}
 	}
 

src/test/skript/tests/syntaxes/effects/EffCopy.sk

@@ -28,3 +28,26 @@ test "single copy":
 
 	copy {_none} into {_foo}
 	assert {_foo} is not set with "Copying nothing didn't delete variable"
+
+test "copy effect type hints":
+	set {_var} to 10
+	copy {_var} into {_x}
+	parse:
+		set {_a} to {_x} in lowercase
+	assert last parse logs contains "Expected variable '{_x}' to be a text, but it is an integer" with "Hint failed (%last parse logs%)"
+	delete {_var}
+	delete {_x}
+
+	set {_var::*} to 10 and 20
+	copy {_var::*} into {_x::*}
+	parse:
+		set {_a::*} to {_x::*} in lowercase
+	assert last parse logs contains "Expected variable '{_x::*}' to be a text, but it is an integer" with "Hint failed (%last parse logs%)"
+	delete {_var::*}
+	delete {_x::*}
+
+	copy pi into {_x}
+	parse:
+		set {_a} to {_x} in lowercase
+	assert last parse logs contains "Expected variable '{_x}' to be a text, but it is a number" with "Hint failed (%last parse logs%)"
+	delete {_foo}

src/test/skript/tests/syntaxes/effects/EffTransform.sk

@@ -27,3 +27,10 @@ test "transform effect":
 	assert {_a::*} is 1, 2, 1, 2, 1 and 2 with "failed to transform with plural expression"
 	assert indices of {_a::*} is "1", "2", "3", "4", "5" and "6" with "transform failed to re-set indices"
 
+
+test "transform effect type hints":
+	set {_x::*} to true and false
+	transform {_x::*} using 0
+	parse:
+		set {_a::*} to {_x::*} in lowercase
+	assert last parse logs contains "Expected variable '{_x::*}' to be a text, but it is an integer" with "Hint failed (%last parse logs%)"

src/test/skript/tests/syntaxes/sections/SecFor.sk

@@ -64,7 +64,8 @@ test "for section":
 	delete {_key}
 	delete {_value}
 
-	# type hints
+test "for section type hints":
+	set {_list::*} to 1, 5, and 10
 	parse:
 		set {_value} to true
 		loop {_key} and {_value} in {_list::*}: