Fix index/call parsing

schala-lang/language/src/parsing/mod.rs

@@ -69,15 +69,21 @@
 //! ```text
 //! expression := precedence_expr type_anno?
 //! precedence_expr := prefix_expr
-//! prefix_expr := prefix_op call_expr
-//! prefix_op := "+" | "-" | "!" | "~"
-//! call_expr := index_expr ( "(" invocation_list ")" )* | ε
-//! invocation_list := invocation_argument ("," invocation_argument)* | ε
-//! invocation_argument := expression | IDENTIFIER "=" expression | "_"
-//! index_expr := primary ( "[" (expression ("," (expression)* | ε) "]" )*
+//! prefix_expr := prefix_op extended_expr
+//!
+//! prefix_op := "+" | "-" | "!" | "~" | ε
+//!
+//! extended_expr := primary (ε | index | call | access)*
+//! index := "[" (expression ("," expression)*) "]"
+//! call := "(" invocation_list ")"
+//! access := "." identifier
 //! primary := literal | paren_expr | if_expr | for_expr | while_expr | identifier_expr | lambda_expr | anonymous_struct | list_expr
 //! expr_or_block := "{" (statement delimiter)* "}" | expr
+//!
+//! invocation_list := invocation_argument ("," invocation_argument)* | ε
+//! invocation_argument := expression | IDENTIFIER "=" expression | "_"
 //! ```
+//! //TODO fix expressions, add accessor_expr as a new thing
 //!
 //! ### Primary expressions
 //!
@@ -688,20 +694,39 @@ impl Parser {
           ExpressionKind::PrefixExp(prefix_op, Box::new(expr))
         ))
       },
-      _ => self.call_expr()
+      _ => self.extended_expr()
     }
   }
 
   #[recursive_descent_method]
-  fn call_expr(&mut self) -> ParseResult<Expression> {
-    let mut expr = self.index_expr()?;
-    //TODO look at this
-    while let LParen = self.token_handler.peek_kind() {
-      let arguments = delimited!(self, LParen, invocation_argument, Comma, RParen);
-      expr = Expression::new(self.id_store.fresh(), ExpressionKind::Call { f: Box::new(expr), arguments }); //TODO no type anno is incorrect
-    }
-
-    Ok(expr)
+  fn extended_expr(&mut self) -> ParseResult<Expression> {
+      let mut expression = self.primary()?;
+      loop {
+          //TODO need a next non whitespace
+          let next = self.token_handler.peek_kind();
+          match next {
+              Period => unimplemented!(),
+              LSquareBracket => {
+                  let indexers = delimited!(self, LSquareBracket, expression, Comma, RSquareBracket);
+                  if indexers.is_empty() {
+                      return ParseError::new_with_token("Empty index expressions are not allowed", self.token_handler.peek());
+                  }
+                  expression = Expression::new(self.id_store.fresh(), ExpressionKind::Index {
+                      indexee: Box::new(expression),
+                      indexers,
+                  });
+              },
+              LParen => {
+                  let arguments = delimited!(self, LParen, invocation_argument, Comma, RParen);
+                  expression = Expression::new(self.id_store.fresh(), ExpressionKind::Call {
+                      f: Box::new(expression),
+                      arguments,
+                  });
+              },
+              _ => break,
+          }
+      }
+      Ok(expression)
   }
 
   #[recursive_descent_method]

schala-lang/language/src/parsing/new_tests.rs

@@ -120,7 +120,6 @@ macro_rules! assert_fail_expr {
         assert_eq!(err.msg, $failure);
     };
 }
-
 #[test]
 fn basic_literals() {
     use ExpressionKind::*;
@@ -202,14 +201,14 @@ fn operators() {
     assert_expr!("a <> 1", binop("<>", expr(Value(qn!(a))), expr(NatLiteral(1))));
 }
 
-//TODO have a test for dot accessors
-/*
-  assert_expr!("a.b.c.d", exst!(binexp!(".",
-                                              binexp!(".",
-                                                binexp!(".", val!("a"), val!("b")),
-                                              val!("c")),
-                                              val!("d"))));
-*/
+#[test]
+fn accessors() {
+    /*
+    assert_expr!("a.b");
+    assert_expr!("a.b.c.d()");
+    assert_expr!("a.b().c.d()");
+    */
+}
 
 #[test]
 fn tuples() {
@@ -273,17 +272,19 @@ fn index() {
             indexers: vec![expr(Value(qn!(b))), expr(Value(qn!(c)))]
         })
     );
-    //TODO this is a parser bug
-    /*
-    assert_expr!("perspicacity()[a]", expr(Index{
-        indexee: bx(expr(Call {
-            f: bx(expr(Value(qn!(perspicacity)))),
-            arguments: vec![]
-        })),
-        indexers: vec![expr(Value(qn!(a)))]
-    }));
-    */
-    //TODO parse_test("a()[b]()[d]")
+    assert_expr!(
+        "perspicacity()[a]",
+        expr(Index {
+            indexee: bx(expr(Call { f: bx(expr(Value(qn!(perspicacity)))), arguments: vec![] })),
+            indexers: vec![expr(Value(qn!(a)))]
+        })
+    );
+
+    let a = expr(Call { f: bx(expr(Value(qn!(a)))), arguments: vec![] });
+    let b = expr(Index { indexee: bx(a), indexers: vec![expr(Value(qn!(b)))] });
+    let c = expr(Call { f: bx(b), arguments: vec![] });
+    let d = expr(Index { indexee: bx(c), indexers: vec![expr(Value(qn!(d)))] });
+    assert_expr!("a()[b]()[d]", d);
 
     assert_fail_expr!("a[]", "Empty index expressions are not allowed");
 }

schala-lang/language/src/tree_walk_eval/test.rs

@@ -1,5 +1,6 @@
 #![cfg(test)]
 use test_case::test_case;
+use pretty_assertions::assert_eq;
 
 use crate::{
     symbol_table::SymbolTable,