Report any statements after return statements as unreachable

ZenCodeLang · Sep 14, 2024 · 78dc709 · 78dc709
1 parent eeb4ebb
commit 78dc709
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Showing 3 changed files with 22 additions and 5 deletions.
diff --git a/CodeModel/src/main/java/org/openzen/zenscript/codemodel/compilation/CompileErrors.java b/CodeModel/src/main/java/org/openzen/zenscript/codemodel/compilation/CompileErrors.java
@@ -571,4 +571,8 @@ public static CompileError invalidPropertyPair(TypeID type, String name) {
 	public static CompileError invalidLambdaHeader(FunctionHeader header) {
 		return new CompileError(CompileExceptionCode.LAMBDA_HEADER_INVALID, "Invalid lambda header " + header);
 	}
+
+	public static CompileError unreachableStatement() {
+		return new CompileError(CompileExceptionCode.UNREACHABLE_STATEMENT, "Unreachable statement");
+	}
 }
diff --git a/ScriptingEngineTester/src/main/resources/zencode_tests/return/return_5.zc b/ScriptingEngineTester/src/main/resources/zencode_tests/return/return_5.zc
@@ -1,4 +1,3 @@
-#disabled: Not part of the refactor
 #error: 10:UNREACHABLE_STATEMENT
 
 function test(check: bool): string {

diff --git a/...ator/src/main/java/org/openzen/zenscript/validator/visitors/ReturnStatementValidator.java b/...ator/src/main/java/org/openzen/zenscript/validator/visitors/ReturnStatementValidator.java
@@ -6,10 +6,14 @@
 import org.openzen.zenscript.codemodel.type.TypeID;
 import org.openzen.zenscript.validator.Validator;
 
-import java.util.Arrays;
-
 public class ReturnStatementValidator implements StatementVisitor<ReturnStatementValidator.ReturnKind> {
 
+	private final Validator validator;
+
+	public ReturnStatementValidator(Validator validator) {
+		this.validator = validator;
+	}
+
 	/**
 	 * Validates whether a given statement appropriately returns a value as required by its return type.
 	 *
@@ -24,7 +28,7 @@ public static void validate(TypeID returnType, Statement statement, Validator va
 			return;
 		}
 
-		ReturnStatementValidator.ReturnKind returnKind = statement.accept(new ReturnStatementValidator());
+		ReturnStatementValidator.ReturnKind returnKind = statement.accept(new ReturnStatementValidator(validator));
 		switch (returnKind) {
 			case ALWAYS_RETURNS:
 				return;
@@ -129,7 +133,17 @@ public ReturnKind visitWhile(WhileStatement statement) {
 	}
 
 	private ReturnKind mergeInsideBlock(Statement[] statements) {
-		return Arrays.stream(statements).map(it -> it.accept(this)).reduce(ReturnKind.NEVER_RETURNS, ReturnKind::max);
+		ReturnKind result = ReturnKind.NEVER_RETURNS;
+		for (Statement statement : statements) {
+			if (result == ReturnKind.ALWAYS_RETURNS) {
+				validator.logError(statement.position, CompileErrors.unreachableStatement());
+				break;
+			}
+
+			result = ReturnKind.max(result, statement.accept(this));
+		}
+
+		return result;
 	}
 
 	public enum ReturnKind {