Put parsing details into one module

parser/src/parsing/create.rs

@@ -0,0 +1,109 @@
+use minisql::{operation::Operation, schema::{ColumnName, TableSchema}, type_system::DbType};
+use nom::{
+    bytes::complete::tag,
+    character::complete::{char, multispace0, multispace1},
+    multi::separated_list0,
+    sequence::terminated,
+    IResult, combinator::opt,
+};
+
+use super::common::{parse_table_name, parse_identifier, parse_db_type};
+
+pub fn parse_create(input: &str) -> IResult<&str, Operation> {
+    let (input, _) = tag("CREATE")(input)?;
+    let (input, _) = multispace1(input)?;
+    let (input, _) = tag("TABLE")(input)?;
+    let (input, _) = multispace1(input)?;
+    let (input, table_name) = parse_table_name(input)?;
+    let (input, _) = multispace0(input)?;
+    let (input, _) = char('(')(input)?;
+    let (input, _) = multispace0(input)?;
+    let (input, column_definitions) = parse_column_definitions(input)?;
+    let mut column_name_position_mapping = Vec::new();
+    let mut types: Vec<DbType> = Vec::new();
+    let mut primary_key = None;
+    for (position, (column_name, db_type, pk)) in column_definitions.iter().enumerate() {
+        types.push(db_type.clone());
+        if *pk {
+            primary_key = Some(position);
+        }
+        column_name_position_mapping.push((column_name.clone(), position));
+    }
+
+    let (input, _) = char(')')(input)?;
+    let (input, _) = multispace0(input)?;
+    let (input, _) = char(';')(input)?;
+    let schema = TableSchema::new(
+        table_name.to_string(),
+        primary_key.unwrap_or_default(),
+        column_name_position_mapping,
+        types
+    );
+    Ok((
+        input,
+        Operation::CreateTable(table_name.to_string(), schema),
+    ))
+}
+
+pub fn parse_column_definitions(input: &str) -> IResult<&str, Vec<(ColumnName, DbType, bool)>> {
+    separated_list0(terminated(char(','), multispace0), parse_column_definition)(input)
+}
+
+fn parse_primary_key(input: &str) -> IResult<&str, &str> {
+    let (input, _) = multispace1(input)?;
+    let (input, _) = tag("PRIMARY")(input)?;
+    let (input, _) = multispace1(input)?;
+    let (input, _) = tag("KEY")(input)?;
+    Ok((input, "PRIMARY KEY"))
+}
+
+pub fn parse_column_definition(input: &str) -> IResult<&str, (ColumnName, DbType, bool)> {
+    let (input, identifier) = parse_identifier(input)?;
+    let (input, _) = multispace1(input)?;
+    let (input, db_type) = parse_db_type(input)?;
+    let (input, pk) = opt(parse_primary_key)(input).map(|(input, pk)| (input, pk.is_some()))?;
+    let (input, _) = multispace0(input)?;
+    Ok((input, (identifier.to_string(), db_type, pk)))
+}
+
+#[cfg(test)]
+mod tests {
+    use minisql::operation::Operation;
+    use crate::parsing::create::parse_create;
+
+    #[test]
+    fn test_parse_create_no_spaces() {
+        parse_create("CREATE TABLE \"Table1\"(id UUID ,column1 INT);").expect("should parse");
+    }
+
+    #[test]
+    fn test_parse_create_primary_key() {
+        parse_create("CREATE TABLE \"Table1\"(id UUID PRIMARY KEY,column1 INT);").expect("should parse");
+    }
+
+    #[test]
+    fn test_parse_create_no_quotes_table_name() {
+        parse_create("CREATE TABLE Table1(id UUID PRIMARY KEY,column1 INT);").expect("should parse");
+    }
+
+    #[test]
+    fn test_parse_create_primary_key_with_spaces() {
+        parse_create("CREATE   TABLE   \"Table1\"  ( id   UUID   PRIMARY   KEY  ,  column1   INT  )  ;").expect("should parse");
+    }
+
+    #[test]
+    fn test_parse_create() {
+        let (_, create) = parse_create("CREATE TABLE \"Table1\"( id UUID , column1 INT );").expect("should parse");
+        assert!(matches!(create, Operation::CreateTable(_ ,_)));
+        match create {
+            Operation::CreateTable(name, schema) => {
+                assert_eq!(name, "Table1");
+                assert_eq!(schema.number_of_columns(), 2);
+                assert_eq!(schema.column_position_from_column_name(&"id".to_string()).unwrap(), 0);
+                assert_eq!(schema.column_position_from_column_name(&"column1".to_string()).unwrap(), 1);
+            }
+            _ => {}
+        }
+
+    }
+}