fix resolving global variables

src/db/engine.rs

@@ -246,7 +246,7 @@ mod tests {
             let engine2 = Engine::new(p2.to_string(), false);
             assert!(engine2.is_ok());
             println!("start ok");
-            let engine2 = Arc::new(Engine::new(p3.to_string(), true).unwrap());
+            let engine2 = Arc::new(Engine::new(p3.to_string(), false).unwrap());
             {
                 for _i in 0..10 {
                     let _sess = engine2.session().unwrap();
@@ -274,9 +274,12 @@ mod tests {
                         sess.define_variable(&gname, &"xyz".into(), true).unwrap();
                         sess.define_variable("pqr", &"xyz".into(), false).unwrap();
                     }
+                    if i & 1 == 0 {
+                        sess.commit().unwrap();
+                    }
                     println!("pqr {:?}", sess.resolve("pqr"));
                     println!("uvw {:?}", sess.resolve("uvw"));
-                    println!("aaa {:?}", sess.resolve(&gname));
+                    println!("aaa {} {:?}", &gname, sess.resolve(&gname));
                     let it = sess.txn.iterator(false, &sess.temp_cf);
                     it.to_first();
                     // for (key, val) in it.iter() {
@@ -286,14 +289,14 @@ mod tests {
                     for _ in 0..5000 {
                         sess.pop_env().unwrap();
                     }
-                    if let Err(e) = sess.commit() {
-                        println!("Err {} with {:?}", i, e);
-                    } else {
-                        println!("OK!!!! {}", i);
-                        sess.commit().unwrap();
-                        sess.commit().unwrap();
-                        println!("OK!!!!!!!! {}", i);
-                    }
+                    // if let Err(e) = sess.commit() {
+                    //     println!("Err {} with {:?}", i, e);
+                    // } else {
+                    //     println!("OK!!!! {}", i);
+                    //     sess.commit().unwrap();
+                    //     sess.commit().unwrap();
+                    //     println!("OK!!!!!!!! {}", i);
+                    // }
                     // sess.commit().unwrap();
                     // sess.commit().unwrap();
                     println!("pqr {:?}", sess.resolve("pqr"));

src/db/eval.rs

@@ -1,49 +1,102 @@
-use cozorocks::SlicePtr;
+use std::collections::BTreeMap;
+use cozorocks::{SlicePtr, StatusCode};
 use crate::db::engine::{Session};
 use crate::relation::table::{Table};
 use crate::relation::tuple::{Tuple};
 use crate::relation::typing::Typing;
 use crate::relation::value::Value;
-use crate::error::Result;
+use crate::error::{CozoError, Result};
 use crate::relation::data::DataKind;
 
 pub trait Environment<T: AsRef<[u8]>> {
+    fn get_stack_depth(&self) -> i32;
     fn push_env(&mut self);
     fn pop_env(&mut self) -> Result<()>;
-    fn define_variable(&mut self, name: &str, val: &Value, in_root: bool) -> Result<()>;
-    fn define_type_alias(&mut self, name: &str, typ: &Typing, in_root: bool) -> Result<()>;
-    fn define_table(&mut self, table: &Table, in_root: bool) -> Result<()>;
-    fn resolve(&self, name: &str) -> Result<Option<Tuple<T>>>;
-    fn delete_defined(&mut self, name: &str, in_root: bool) -> Result<()>;
-}
+    fn define_variable(&mut self, name: &str, val: &Value, in_root: bool) -> Result<()> {
+        let mut data = Tuple::with_data_prefix(DataKind::Value);
+        data.push_value(val);
+        self.define_data(name, data, in_root)
+    }
 
+    fn define_type_alias(&mut self, name: &str, typ: &Typing, in_root: bool) -> Result<()> {
+        let mut data = Tuple::with_data_prefix(DataKind::TypeAlias);
+        data.push_str(typ.to_string());
+        self.define_data(name, data, in_root)
+    }
 
-impl<'a> Session<'a> {
+    fn define_table(&mut self, table: &Table, in_root: bool) -> Result<()> {
+        todo!()
+    }
+    fn resolve(&self, name: &str) -> Result<Option<Tuple<T>>>;
+    fn delete_defined(&mut self, name: &str, in_root: bool) -> Result<()>;
+    fn define_data(&mut self, name: &str, data: Tuple<Vec<u8>>, in_root: bool) -> Result<()>;
     fn encode_definable_key(&self, name: &str, in_root: bool) -> Tuple<Vec<u8>> {
-        let depth_code = if in_root { 0 } else { self.stack_depth as i64 };
+        let depth_code = if in_root { 0 } else { self.get_stack_depth() as i64 };
         let mut tuple = Tuple::with_null_prefix();
         tuple.push_str(name);
         tuple.push_int(depth_code);
         tuple
     }
+}
 
-    fn define_data(&mut self, name: &str, data: Tuple<Vec<u8>>, in_root: bool) -> Result<()> {
-        let key = self.encode_definable_key(name, in_root);
-        if in_root {
-            self.txn.put(true, &self.perm_cf, key, data)?;
-        } else {
-            let mut ikey = Tuple::with_null_prefix();
-            ikey.push_int(self.stack_depth as i64);
-            ikey.push_str(name);
-            self.txn.put(false, &self.temp_cf, key, data)?;
-            self.txn.put(false, &self.temp_cf, ikey, "")?;
+pub struct MemoryEnv {
+    root: BTreeMap<String, Tuple<Vec<u8>>>,
+    stack: Vec<BTreeMap<String, Tuple<Vec<u8>>>>,
+}
+
+impl Default for MemoryEnv {
+    fn default() -> Self {
+        MemoryEnv { root: BTreeMap::default(), stack: vec![BTreeMap::default()] }
+    }
+}
+
+impl Environment<Tuple<Vec<u8>>> for MemoryEnv {
+    fn get_stack_depth(&self) -> i32 {
+        -(self.stack.len() as i32)
+    }
+
+    fn push_env(&mut self) {
+        self.stack.push(BTreeMap::default());
+    }
+
+    fn pop_env(&mut self) -> Result<()> {
+        if self.stack.len() > 1 {
+            self.stack.pop();
         }
         Ok(())
     }
+
+    fn define_variable(&mut self, name: &str, val: &Value, in_root: bool) -> Result<()> {
+        todo!()
+    }
+
+    fn define_type_alias(&mut self, name: &str, typ: &Typing, in_root: bool) -> Result<()> {
+        todo!()
+    }
+
+    fn define_table(&mut self, table: &Table, in_root: bool) -> Result<()> {
+        todo!()
+    }
+
+    fn resolve(&self, name: &str) -> Result<Option<Tuple<Tuple<Vec<u8>>>>> {
+        todo!()
+    }
+
+    fn delete_defined(&mut self, name: &str, in_root: bool) -> Result<()> {
+        todo!()
+    }
+
+    fn define_data(&mut self, name: &str, data: Tuple<Vec<u8>>, in_root: bool) -> Result<()> {
+        todo!()
+    }
 }
 
 
 impl<'a> Environment<SlicePtr> for Session<'a> {
+    fn get_stack_depth(&self) -> i32 {
+        self.stack_depth
+    }
+
     fn push_env(&mut self) {
         self.stack_depth -= 1;
     }
@@ -76,48 +129,29 @@ impl<'a> Environment<SlicePtr> for Session<'a> {
         Ok(())
     }
 
-    fn define_variable(&mut self, name: &str, val: &Value, in_root: bool) -> Result<()> {
-        let mut data = Tuple::with_data_prefix(DataKind::Value);
-        data.push_value(val);
-        self.define_data(name, data, in_root)
-    }
-
-    fn define_type_alias(&mut self, name: &str, typ: &Typing, in_root: bool) -> Result<()> {
-        let mut data = Tuple::with_data_prefix(DataKind::TypeAlias);
-        data.push_str(typ.to_string());
-        self.define_data(name, data, in_root)
-    }
-
-    fn define_table(&mut self, table: &Table, in_root: bool) -> Result<()> {
-        todo!()
-    }
-
     fn resolve(&self, name: &str) -> Result<Option<Tuple<SlicePtr>>> {
         let mut tuple = Tuple::with_null_prefix();
         tuple.push_str(name);
         let it = self.txn.iterator(false, &self.temp_cf);
         it.seek(&tuple);
-        Ok(match it.pair() {
-            None => {
-                None
-            }
-            Some((tk, vk)) => {
-                let k = Tuple::new(tk);
-                if k.starts_with(&tuple) {
-                    println!("Resolved to key {:?}", k);
-                    Some(Tuple::new(vk))
-                } else {
-                    None
-                }
+        if let Some((tk, vk)) = it.pair() {
+            let k = Tuple::new(tk);
+            if k.starts_with(&tuple) {
+                return Ok(Some(Tuple::new(vk)));
             }
-        })
+        }
+        let root_key = self.encode_definable_key(name, true);
+        match self.txn.get(true, &self.perm_cf, root_key) {
+            Ok(root_res) => Ok(Some(Tuple::new(root_res))),
+            Err(e) if e.status.code == StatusCode::kNotFound => Ok(None),
+            Err(e) => Err(CozoError::Bridge(e))
+        }
     }
 
     fn delete_defined(&mut self, name: &str, in_root: bool) -> Result<()> {
         let key = self.encode_definable_key(name, in_root);
         if in_root {
             self.txn.del(true, &self.perm_cf, key)?;
-
         } else {
             let it = self.txn.iterator(false, &self.temp_cf);
             it.seek(&key);
@@ -129,7 +163,6 @@ impl<'a> Environment<SlicePtr> for Session<'a> {
                     ikey.push_value(&found_key_tuple.get(0).unwrap());
                     self.txn.del(false, &self.temp_cf, found_key_tuple)?;
                     self.txn.del(false, &self.temp_cf, ikey)?;
-
                 }
             }
         }
@@ -137,4 +170,18 @@ impl<'a> Environment<SlicePtr> for Session<'a> {
 
         Ok(())
     }
+
+    fn define_data(&mut self, name: &str, data: Tuple<Vec<u8>>, in_root: bool) -> Result<()> {
+        let key = self.encode_definable_key(name, in_root);
+        if in_root {
+            self.txn.put(true, &self.perm_cf, key, data)?;
+        } else {
+            let mut ikey = Tuple::with_null_prefix();
+            ikey.push_int(self.stack_depth as i64);
+            ikey.push_str(name);
+            self.txn.put(false, &self.temp_cf, key, data)?;
+            self.txn.put(false, &self.temp_cf, ikey, "")?;
+        }
+        Ok(())
+    }
 }

src/db/table_def.rs

@@ -7,4 +7,31 @@ impl<'a> Session<'a> {
     pub fn parse_table_def(&self, pair: Pair<Rule>) -> Tuple<Vec<u8>> {
         todo!()
     }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::parser::Parser;
+    use pest::Parser as PestParser;
+
+    #[test]
+    fn node() {
+        let s = r#"
+            create node "Person" {
+                *id: Int,
+                name: String,
+                email: ?String,
+                habits: ?[?String]
+            }
+
+            create edge (Person)-[Friend]->(Person) {
+                relation: ?String
+            }
+        "#;
+        let mut parsed = Parser::parse(Rule::file, s).unwrap();
+        let first_t = parsed.next().unwrap().into_inner().next().unwrap();
+        let second_t = parsed.next().unwrap().into_inner().next().unwrap();
+        println!("{:#?}", first_t);
+    }
 }