Replace unnecessary ElseClauseASTNode

include/compiler/parser/ASTNodes.h

@@ -28,7 +28,6 @@ enum ASTNodeType {
 	NODE_ARGUMENT_LIST,
 	NODE_FUNCTION_CALL,
 	NODE_IF_STATEMENT,
-	NODE_ELSE_CLAUSE,
 	NODE_PATTERN,
 	NODE_CONDITION,
 	NODE_OPTIONAL_BINDING_CONDITION,
@@ -205,18 +204,11 @@ typedef struct ConditionASTNode {
 	OptionalBindingConditionASTNode *optionalBindingCondition;
 } ConditionASTNode;
 
-typedef struct ElseClauseASTNode {
-	enum ASTNodeType _type;
-	struct IfStatementASTNode *ifStatement;
-	BlockASTNode *body;
-	bool isElseIf;
-} ElseClauseASTNode;
-
 typedef struct IfStatementASTNode {
 	enum ASTNodeType _type;
 	ConditionASTNode *condition;
 	BlockASTNode *body;
-	ElseClauseASTNode *elseClause;
+	ASTNode /* BlockASTNode | IfStatementASTNode | null */ *alternate;
 } IfStatementASTNode;
 
 typedef struct WhileStatementASTNode {
@@ -256,8 +248,7 @@ FunctionCallASTNode* new_FunctionCallASTNode(IdentifierASTNode *id, ArgumentList
 PatternASTNode* new_PatternASTNode(IdentifierASTNode *id, TypeReferenceASTNode *type);
 OptionalBindingConditionASTNode* new_OptionalBindingConditionASTNode(PatternASTNode *pattern, ExpressionASTNode *initializer, bool isConstant);
 ConditionASTNode* new_ConditionASTNode(ExpressionASTNode *expression, OptionalBindingConditionASTNode *optionalBindingCondition);
-ElseClauseASTNode* new_ElseClauseASTNode(IfStatementASTNode *ifStatement, BlockASTNode *body, bool isElseIf);
-IfStatementASTNode* new_IfStatementASTNode(ConditionASTNode *condition,  BlockASTNode *body, ElseClauseASTNode *elseClause);
+IfStatementASTNode* new_IfStatementASTNode(ConditionASTNode *condition,  BlockASTNode *body, ASTNode *alternate);
 WhileStatementASTNode* new_WhileStatementASTNode(ConditionASTNode *condition,  BlockASTNode *body);
 AssignmentStatementASTNode* new_AssignmentStatementASTNode(IdentifierASTNode *id, ExpressionASTNode *assignment);
 

src/compiler/parser/ASTNodes.c

@@ -184,27 +184,15 @@ ConditionASTNode * new_ConditionASTNode(
 	return node;
 }
 
-ElseClauseASTNode * new_ElseClauseASTNode(
-	IfStatementASTNode *ifStatement,
-	BlockASTNode *body,
-	bool isElseIf
-) {
-	prepare_node_of(ElseClauseASTNode, NODE_ELSE_CLAUSE)
-	node->ifStatement = ifStatement;
-	node->body = body;
-	node->isElseIf = isElseIf;
-	return node;
-}
-
 IfStatementASTNode * new_IfStatementASTNode(
 	ConditionASTNode *condition,
 	BlockASTNode *body,
-	ElseClauseASTNode *elseClause
+	ASTNode *alternate
 ) {
 	prepare_node_of(IfStatementASTNode, NODE_IF_STATEMENT)
 	node->condition = condition;
 	node->body = body;
-	node->elseClause = elseClause;
+	node->alternate = alternate;
 	return node;
 }
 
@@ -243,12 +231,12 @@ BinaryExpressionASTNode* new_BinaryExpressionASTNode(
 UnaryExpressionASTNode* new_UnaryExpressionASTNode(
 	ExpressionASTNode *argument,
 	OperatorType operator
-	//bool IsPrefix
+	// bool IsPrefix
 ) {
 	prepare_node_of(UnaryExpressionASTNode, NODE_UNARY_EXPRESSION)
 	node->argument = argument;
 	node->operator = operator;
-	//node->isPrefix = isPrefix;
+	// node->isPrefix = isPrefix;
 	return node;
 }
 

src/compiler/parser/Parser.c

@@ -21,7 +21,6 @@ ParserResult __Parser_parseFuncStatement(Parser *parser);
 ParserResult __Parser_parsePattern(Parser *parser);
 ParserResult __Parser_parseOptionalBindingCondition(Parser *parser);
 ParserResult __Parser_parseCondition(Parser *parser);
-ParserResult __Parser_parseElseClause(Parser *parser);
 ParserResult __Parser_parseIfStatement(Parser *parser);
 ParserResult __Parser_parseWhileStatement(Parser *parser);
 ParserResult __Parser_parseReturnStatement(Parser *parser);
@@ -506,40 +505,6 @@ ParserResult __Parser_parseCondition(Parser *parser) {
 	return ParserSuccess(condition);
 }
 
-ParserResult __Parser_parseElseClause(Parser *parser) {
-	assertf(parser != NULL);
-
-	// skip else keyword
-	LexerResult result = Lexer_nextToken(parser->lexer);
-	if(!result.success) return LexerToParserError(result);
-
-	LexerResult peek = Lexer_peekToken(parser->lexer, 1);
-	if(!peek.success) return LexerToParserError(peek);
-
-	IfStatementASTNode *ifStatement = NULL;
-	bool isElseIf = false;
-	BlockASTNode *body = NULL;
-
-	if(peek.token->kind == TOKEN_IF) {
-		// consume if keyword
-		result = Lexer_nextToken(parser->lexer);
-		if(!result.success) return LexerToParserError(result);
-
-		ParserResult ifStatementResult = __Parser_parseIfStatement(parser);
-		if(!ifStatementResult.success) return ifStatementResult;
-		ifStatement = (IfStatementASTNode*)ifStatementResult.node;
-		isElseIf = true;
-	} else {
-		ParserResult blockResult = __Parser_parseBlock(parser, true);
-		if(!blockResult.success) return blockResult;
-		body = (BlockASTNode*)blockResult.node;
-	}
-
-	ElseClauseASTNode *elseClause = new_ElseClauseASTNode(ifStatement, body, isElseIf);
-
-	return ParserSuccess(elseClause);
-}
-
 ParserResult __Parser_parseIfStatement(Parser *parser) {
 	assertf(parser != NULL);
 
@@ -569,15 +534,33 @@ ParserResult __Parser_parseIfStatement(Parser *parser) {
 	peek = Lexer_peekToken(parser->lexer, 1);
 	if(!peek.success) return LexerToParserError(peek);
 
-	ElseClauseASTNode *elseClause = NULL;
+	ASTNode *alternate = NULL;
 
 	if(peek.token->kind == TOKEN_ELSE) {
-		ParserResult elseClauseResult = __Parser_parseElseClause(parser);
-		if(!elseClauseResult.success) return elseClauseResult;
-		elseClause = (ElseClauseASTNode*)elseClauseResult.node;
+		// skip else keyword
+		LexerResult result = Lexer_nextToken(parser->lexer);
+		if(!result.success) return LexerToParserError(result);
+
+		LexerResult peek = Lexer_peekToken(parser->lexer, 1);
+		if(!peek.success) return LexerToParserError(peek);
+
+		if(peek.token->kind == TOKEN_IF) {
+			// consume if keyword
+			result = Lexer_nextToken(parser->lexer);
+			if(!result.success) return LexerToParserError(result);
+
+			ParserResult ifStatementResult = __Parser_parseIfStatement(parser);
+			if(!ifStatementResult.success) return ifStatementResult;
+			alternate = (ASTNode*)ifStatementResult.node;
+
+		} else {
+			ParserResult blockResult = __Parser_parseBlock(parser, true);
+			if(!blockResult.success) return blockResult;
+			alternate = (ASTNode*)blockResult.node;
+		}
 	}
 
-	IfStatementASTNode *ifStatement = new_IfStatementASTNode((ConditionASTNode*)conditionResult.node,  (BlockASTNode*)blockResult.node, (ElseClauseASTNode*)elseClause);
+	IfStatementASTNode *ifStatement = new_IfStatementASTNode((ConditionASTNode*)conditionResult.node,  (BlockASTNode*)blockResult.node, (ASTNode*)alternate);
 
 	return ParserSuccess(ifStatement);
 }

test/compiler/parser/Parser.test.c

@@ -520,7 +520,7 @@ DESCRIBE(if_statement, "If statement parsing") {
 		EXPECT_EQUAL_INT(arr->size, 0);
 
 		// else
-		EXPECT_NULL(if_statement->elseClause);
+		EXPECT_NULL(if_statement->alternate);
 
 	} TEST_END();
 
@@ -549,14 +549,9 @@ DESCRIBE(if_statement, "If statement parsing") {
 		EXPECT_NULL(arr->data);
 		EXPECT_EQUAL_INT(arr->size, 0);
 
-		// else
-		EXPECT_NOT_NULL(if_statement->elseClause);
-		EXPECT_FALSE(if_statement->elseClause->isElseIf);
-		EXPECT_NULL(if_statement->elseClause->ifStatement);
-		EXPECT_NOT_NULL(if_statement->elseClause->body);
-
 		// else body
-		body = if_statement->elseClause->body;
+		EXPECT_TRUE(if_statement->alternate->_type == NODE_BLOCK);
+		body = (BlockASTNode*)if_statement->alternate;
 		EXPECT_NOT_NULL(body->statements);
 		arr = body->statements;
 		EXPECT_NULL(arr->data);
@@ -602,11 +597,11 @@ DESCRIBE(if_statement, "If statement parsing") {
 		EXPECT_EQUAL_INT(arr->size, 0);
 
 		// else if
-		EXPECT_NOT_NULL(if_statement->elseClause);
-		EXPECT_TRUE(if_statement->elseClause->isElseIf);
-		EXPECT_NOT_NULL(if_statement->elseClause->ifStatement);
+		EXPECT_NOT_NULL(if_statement->alternate);
+
+		EXPECT_TRUE(if_statement->alternate->_type == NODE_IF_STATEMENT);
 
-		IfStatementASTNode *elseif = if_statement->elseClause->ifStatement;
+		IfStatementASTNode *elseif = (IfStatementASTNode*)if_statement->alternate;
 
 		EXPECT_NOT_NULL(elseif->condition);
 		EXPECT_TRUE(elseif->condition->_type == NODE_CONDITION);
@@ -635,14 +630,9 @@ DESCRIBE(if_statement, "If statement parsing") {
 		EXPECT_NULL(arr->data);
 		EXPECT_EQUAL_INT(arr->size, 0);
 
-		// else
-		EXPECT_NOT_NULL(elseif->elseClause);
-		EXPECT_FALSE(elseif->elseClause->isElseIf);
-		EXPECT_NULL(elseif->elseClause->ifStatement);
-		EXPECT_NOT_NULL(elseif->elseClause->body);
-
 		// else body
-		body = elseif->elseClause->body;
+		EXPECT_TRUE(elseif->alternate->_type == NODE_BLOCK);
+		body = (BlockASTNode*)elseif->alternate;
 		EXPECT_NOT_NULL(body->statements);
 		arr = body->statements;
 		EXPECT_NULL(arr->data);
@@ -705,7 +695,7 @@ DESCRIBE(if_statement, "If statement parsing") {
 		EXPECT_EQUAL_INT(arr->size, 0);
 
 		// else
-		EXPECT_NULL(if_statement->elseClause);
+		EXPECT_NULL(if_statement->alternate);
 
 	} TEST_END();
 }