Implemented widening conversions on basic type comparison

Author: stanhebben

CodeModel/src/main/java/org/openzen/zenscript/codemodel/compilation/CompileErrors.java

@@ -24,6 +24,10 @@ public static CompileError ambiguousType(List<TypeID> candidates) {
 		return new CompileError(CompileExceptionCode.INFERENCE_AMBIGUOUS, "Type inference ambiguity, possible types: " + possibleTypes);
 	}
 
+	public static CompileError cannotCompare(TypeID a, TypeID b) {
+		return new CompileError(CompileExceptionCode.CANNOT_COMPARE, "Cannot compare " + a + " and " + b);
+	}
+
 	public static CompileError ambiguousComparison(TypeID a, TypeID b) {
 		return new CompileError(CompileExceptionCode.AMBIGUOUS_COMPARISON, "Ambiguous comparison, not sure to compare as " + a + " or " + b);
 	}

CodeModel/src/main/java/org/openzen/zenscript/codemodel/type/builtin/BasicTypeMembers.java

@@ -5,6 +5,7 @@
 import org.openzen.zenscript.codemodel.OperatorType;
 import org.openzen.zenscript.codemodel.compilation.CastedEval;
 import org.openzen.zenscript.codemodel.compilation.CastedExpression;
+import org.openzen.zenscript.codemodel.compilation.CompileErrors;
 import org.openzen.zenscript.codemodel.expression.CompareExpression;
 import org.openzen.zenscript.codemodel.expression.Expression;
 import org.openzen.zenscript.codemodel.identifiers.MethodID;
@@ -14,6 +15,8 @@
 import org.openzen.zenscript.codemodel.type.TypeID;
 import org.openzen.zenscript.codemodel.type.member.MemberSet;
 
+import java.util.Optional;
+
 public class BasicTypeMembers {
 	private static final MemberSet NO_MEMBERS = new MemberSet();
 	private static final MethodID CONSTRUCTOR = MethodID.operator(OperatorType.CONSTRUCTOR);
@@ -549,7 +552,7 @@ private static MemberSet getString() {
 	private static void setup(MemberSet.Builder builder, BasicTypeID type) {
 		for (BuiltinMethodSymbol method : BuiltinMethodSymbol.values()) {
 			if (method.getDefiningType().equals(type) && method.getID().equals(COMPARE)) {
-				comparator(builder, method, method.getHeader().getParameterType(false, 0));
+				comparator(builder);
 			}/* else if (method.getID().equals(CONSTRUCTOR)) {
 				builder.constructor(new MethodInstance(method));
 			} else if (method.getDefiningType() == type) {
@@ -583,23 +586,46 @@ private static void setup(MemberSet.Builder builder, BasicTypeID type) {
 		}
 	}
 
-	private static void comparator(MemberSet.Builder builder, BuiltinMethodSymbol method, TypeID ofType) {
-		MethodInstance comparator = new MethodInstance(method);
+	private static void comparator(MemberSet.Builder builder) {
 		builder.comparator(((compiler, position, left, right, type) -> {
-			CastedExpression casted = right.cast(CastedEval.implicit(compiler, position, ofType));
-			if (casted.isFailed())
-				return casted;
-
-			Expression value = new CompareExpression(
-					position,
-					left,
-					casted.value,
-					comparator,
-					type);
-			return new CastedExpression(casted.level, value);
+			Expression rightCompiled = right.eval();
+			Optional<TypeID> union = compiler.union(left.type, rightCompiled.type);
+			return union.map(typeID -> {
+				CastedEval cast = new CastedEval(compiler, left.position, typeID, false, false);
+				Expression castedLeft = cast.of(left).value;
+				Expression castedRight = cast.of(rightCompiled).value;
+				Expression value = new CompareExpression(
+						position,
+						castedLeft,
+						castedRight,
+						new MethodInstance(getComparator((BasicTypeID) typeID)),
+						type);
+				return new CastedExpression(CastedExpression.Level.EXACT, value);
+			}).orElseGet(() -> {
+				return new CastedExpression(CastedExpression.Level.INVALID, compiler.at(position).invalid(CompileErrors.cannotCompare(left.type, rightCompiled.type)));
+			});
 		}));
 	}
 
+	private static BuiltinMethodSymbol getComparator(BasicTypeID type) {
+		switch (type) {
+			case BYTE: return BuiltinMethodSymbol.BYTE_COMPARE;
+			case SBYTE: return BuiltinMethodSymbol.SBYTE_COMPARE;
+			case SHORT: return BuiltinMethodSymbol.SHORT_COMPARE;
+			case USHORT: return BuiltinMethodSymbol.USHORT_COMPARE;
+			case INT: return BuiltinMethodSymbol.INT_COMPARE;
+			case UINT: return BuiltinMethodSymbol.UINT_COMPARE;
+			case LONG: return BuiltinMethodSymbol.LONG_COMPARE;
+			case ULONG: return BuiltinMethodSymbol.ULONG_COMPARE;
+			case USIZE: return BuiltinMethodSymbol.USIZE_COMPARE;
+			case FLOAT: return BuiltinMethodSymbol.FLOAT_COMPARE;
+			case DOUBLE: return BuiltinMethodSymbol.DOUBLE_COMPARE;
+			case CHAR: return BuiltinMethodSymbol.CHAR_COMPARE;
+			case STRING: return BuiltinMethodSymbol.STRING_COMPARE;
+			default: throw new IllegalArgumentException("No comparator for " + type);
+		}
+	}
+
 	private static MethodInstance[] getWideningMethodInstances(BuiltinMethodSymbol method) {
 		FunctionHeader original = method.getHeader();
 		if (original.parameters.length != 1)

Parser/src/main/java/org/openzen/zenscript/parser/expression/ParsedExpressionConditional.java

@@ -49,13 +49,16 @@ public Compiling(
 
 		@Override
 		public Expression eval() {
-			Expression condition = this.condition.cast(cast(BasicTypeID.BOOL)).value;
+			CastedExpression condition = this.condition.cast(cast(BasicTypeID.BOOL));
+			if (condition.isFailed())
+				return condition.value;
+
 			Expression ifThen = this.ifThen.eval();
 			Expression ifElse = this.ifElse.eval();
 			return compiler.union(ifThen.type, ifElse.type)
 					.map(t -> {
 						CastedEval cast = cast(t);
-						return compiler.at(position).ternary(condition, cast.of(ifThen).value, cast.of(ifElse).value);
+						return compiler.at(position).ternary(condition.value, cast.of(ifThen).value, cast.of(ifElse).value);
 					})
 					.orElseGet(() -> compiler.at(position).invalid(CompileErrors.noIntersectionBetweenTypes(ifThen.type, ifElse.type)));
 		}

ScriptingEngineTester/src/main/resources/zencode-tests/operators/compare-1.zc

@@ -2,12 +2,12 @@
 #output: true
 #output: true
 #output: true
-#output: false
-
-println("" + ((3 < 5) ? "true" : "false"));
-println("" + ((3 < (5 as usize)) ? "true" : "false"));
-println("" + ((3 < 5.0) ? "true" : "false"));
-println("" + ((3 < 5.0f) ? "true" : "false"));
-println("" + (3 < 0x40 ? "true" : "false"));
+#output: true
+#output: true
 
-println("" + ((-5 < (3 as usize)) ? "true" : "false")); //What does this return?
+println("" + ((3 < 5)));
+println("" + ((3 < (5 as usize))));
+println("" + ((3 < 5.0)));
+println("" + ((3 < 5.0f)));
+println("" + (3 < 0x40));
+println("" + ((-5 < (3 as usize)))); // interpreted as int

Shared/src/main/java/org/openzen/zencode/shared/CompileExceptionCode.java

@@ -75,6 +75,7 @@ public enum CompileExceptionCode {
 	INVALID_ARRAY_TYPE,
 	INFERENCE_AMBIGUOUS,
 	AMBIGUOUS_COMPARISON,
+	CANNOT_COMPARE,
 	NOT_AN_EXPRESSION,
 	INCOMPLETE_HEADER,
 	INCOMPLETE_IMPLEMENTATION,