[#138] parser::common 테스트코드 작성

src/ast/dml/expressions/subquery.rs

@@ -7,6 +7,12 @@ pub enum SubqueryExpression {
     Select(Box<SelectQuery>),
 }
 
+impl Default for SubqueryExpression {
+    fn default() -> Self {
+        SubqueryExpression::Select(Box::new(SelectQuery::builder()))
+    }
+}
+
 impl From<SubqueryExpression> for SQLExpression {
     fn from(value: SubqueryExpression) -> SQLExpression {
         SQLExpression::Subquery(value)

src/ast/types/column.rs

@@ -3,7 +3,7 @@ use serde::{Deserialize, Serialize};
 
 use super::expression::SQLExpression;
 
-#[derive(Deserialize, Serialize, Clone, Debug, PartialEq)]
+#[derive(Deserialize, Serialize, Clone, Debug, PartialEq, Default)]
 pub struct Column {
     pub name: String,
     pub data_type: DataType,

src/ast/types/data_types.rs

@@ -9,6 +9,12 @@ pub enum DataType {
     Varchar(i64),
 }
 
+impl Default for DataType {
+    fn default() -> Self {
+        DataType::Int
+    }
+}
+
 impl DataType {
     pub fn type_code(&self) -> isize {
         match self {

src/parser/implements/common.rs

@@ -449,37 +449,6 @@ impl Parser {
         }
     }
 
-    // 다음 토큰이 여는 괄호인지
-    pub(crate) fn _next_token_is_subquery(&mut self) -> bool {
-        if !self.has_next_token() {
-            false
-        } else {
-            let current_token = self.get_next_token();
-
-            if current_token == Token::LeftParentheses {
-                if !self.has_next_token() {
-                    self.unget_next_token(current_token);
-                    false
-                } else {
-                    let second_token = self.get_next_token();
-
-                    if second_token == Token::Select {
-                        self.unget_next_token(second_token);
-                        self.unget_next_token(current_token);
-                        true
-                    } else {
-                        self.unget_next_token(second_token);
-                        self.unget_next_token(current_token);
-                        false
-                    }
-                }
-            } else {
-                self.unget_next_token(current_token);
-                false
-            }
-        }
-    }
-
     // 다음 토큰이 닫는 괄호인지
     pub(crate) fn next_token_is_right_parentheses(&mut self) -> bool {
         if !self.has_next_token() {