Improve error output; Add syntax error check

examples/jq_data.ds

@@ -4,8 +4,8 @@ new_data = []
 
 for commit_data in data {	
 	new_data += {
-		message = commit_data.commit.message
+		message = commit_data:commit:message
-		name = commit_data.commit.committer.name
+		name = commit_data:commit:committer:name
 	}
 }
 

src/error.rs

@@ -397,10 +397,14 @@ impl fmt::Display for Error {
                 actual,
                 location,
                 relevant_source,
-            } => write!(
+            } => {
+                let location = get_position(location);
+
+                write!(
                     f,
                     "Expected {expected}, but got {actual} at {location}. Code: {relevant_source} ",
-            ),
+                )
+            }
             WrongColumnAmount { expected, actual } => write!(
                 f,
                 "Wrong column amount. Expected {expected} but got {actual}."
@@ -408,7 +412,9 @@ impl fmt::Display for Error {
             External(message) => write!(f, "External error: {message}"),
             CustomMessage(message) => write!(f, "{message}"),
             Syntax { source, location } => {
-                write!(f, "Syntax error at {location}, this is not valid: {source}")
+                let location = get_position(location);
+
+                write!(f, "Syntax error at {location}: {source}")
             }
             TypeCheck { expected, actual } => write!(
                 f,
@@ -418,7 +424,11 @@ impl fmt::Display for Error {
                 error,
                 location,
                 source,
-            } => write!(f, "{error} Occured at {location}: \"{source}\""),
+            } => {
+                let location = get_position(location);
+
+                write!(f, "{error} Occured at {location}: \"{source}\"")
+            }
             SerdeJson(message) => write!(f, "JSON processing error: {message}"),
             ParserCancelled => write!(
                 f,
@@ -427,3 +437,7 @@ impl fmt::Display for Error {
         }
     }
 }
+
+fn get_position(position: &Point) -> String {
+    format!("column {}, row {}", position.row + 1, position.column)
+}

src/interpret.rs

@@ -2,7 +2,7 @@
 //!
 //! You can use this library externally by calling either of the "eval"
 //! functions or by constructing your own Evaluator.
-use tree_sitter::{Parser, Tree as TSTree};
+use tree_sitter::{Node, Parser, Tree as TSTree, TreeCursor};
 
 use crate::{language, AbstractTree, Error, Map, Result, Root, Value};
 
@@ -69,12 +69,39 @@ impl Interpreter {
         })
     }
 
-    pub fn parse_only(&mut self, source: &str) {
+    pub fn parse(&mut self, source: &str) -> Result<()> {
-        self.syntax_tree = self.parser.parse(source, self.syntax_tree.as_ref());
+        fn check_for_error(source: &str, node: Node, cursor: &mut TreeCursor) -> Result<()> {
+            if node.is_error() {
+                Err(Error::Syntax {
+                    source: source[node.byte_range()].to_string(),
+                    location: node.start_position(),
+                })
+            } else {
+                for child in node.children(&mut cursor.clone()) {
+                    check_for_error(source, child, cursor)?;
+                }
+
+                Ok(())
+            }
+        }
+
+        let syntax_tree = self.parser.parse(source, None);
+
+        if let Some(tree) = &syntax_tree {
+            let root = tree.root_node();
+            let mut cursor = root.walk();
+
+            check_for_error(source, root, &mut cursor)?;
+        }
+
+        self.syntax_tree = syntax_tree;
+
+        Ok(())
     }
 
     pub fn run(&mut self, source: &str) -> Result<Value> {
-        self.syntax_tree = self.parser.parse(source, self.syntax_tree.as_ref());
+        self.parse(source)?;
+
         self.abstract_tree = if let Some(syntax_tree) = &self.syntax_tree {
             Some(Root::from_syntax_node(
                 source,

src/main.rs

@@ -75,7 +75,7 @@ fn main() {
     let mut interpreter = Interpreter::new(context).unwrap();
 
     if args.show_syntax_tree {
-        interpreter.parse_only(&source);
+        interpreter.parse(&source).unwrap();
 
         println!("{}", interpreter.syntax_tree().unwrap());
     }

test.ds

@@ -0,0 +1,2 @@
+fn = (x <int>) <none> {}
+fn(1)

tests/interpret.rs

@@ -94,27 +94,27 @@ mod value {
     use dust_lang::*;
 
     #[test]
-    fn interpret_empty() {
+    fn empty() {
         assert_eq!(interpret("x = 9"), Ok(Value::Option(None)));
         assert_eq!(interpret("x = 1 + 1"), Ok(Value::Option(None)));
     }
 
     #[test]
-    fn interpret_integer() {
+    fn integer() {
         assert_eq!(interpret("1"), Ok(Value::Integer(1)));
         assert_eq!(interpret("123"), Ok(Value::Integer(123)));
         assert_eq!(interpret("-666"), Ok(Value::Integer(-666)));
     }
 
     #[test]
-    fn interpret_float() {
+    fn float() {
         assert_eq!(interpret("0.1"), Ok(Value::Float(0.1)));
         assert_eq!(interpret("12.3"), Ok(Value::Float(12.3)));
         assert_eq!(interpret("-6.66"), Ok(Value::Float(-6.66)));
     }
 
     #[test]
-    fn interpret_string() {
+    fn string() {
         assert_eq!(interpret("\"one\""), Ok(Value::String("one".to_string())));
         assert_eq!(interpret("'one'"), Ok(Value::String("one".to_string())));
         assert_eq!(interpret("`one`"), Ok(Value::String("one".to_string())));
@@ -127,7 +127,7 @@ mod value {
     }
 
     #[test]
-    fn interpret_list() {
+    fn list() {
         assert_eq!(
             interpret("[1, 2, 'foobar']"),
             Ok(Value::List(List::with_items(vec![
@@ -139,7 +139,7 @@ mod value {
     }
 
     #[test]
-    fn interpret_map() {
+    fn map() {
         let map = Map::new();
 
         map.set("x".to_string(), Value::Integer(1), None).unwrap();
@@ -150,7 +150,7 @@ mod value {
     }
 
     #[test]
-    fn interpret_map_types() {
+    fn map_types() {
         let map = Map::new();
 
         map.set("x".to_string(), Value::Integer(1), Some(Type::Integer))
@@ -169,7 +169,7 @@ mod value {
     }
 
     #[test]
-    fn interpret_map_type_errors() {
+    fn map_type_errors() {
         assert!(interpret("{ foo <bool> = 'bar' }")
             .unwrap_err()
             .is_type_check_error(&Error::TypeCheck {
@@ -179,15 +179,15 @@ mod value {
     }
 
     #[test]
-    fn interpret_function() {
+    fn function() {
-        let result = interpret("() -> <int> { 1 }");
+        let result = interpret("() <int> { 1 }");
         let value = result.unwrap();
         let function = value.as_function().unwrap();
 
         assert_eq!(&Vec::<Identifier>::with_capacity(0), function.parameters());
         assert_eq!(&Type::Integer, function.return_type());
 
-        let result = interpret("(x <bool>) -> <bool> {true}");
+        let result = interpret("(x <bool>) <bool> { true }");
         let value = result.unwrap();
         let function = value.as_function().unwrap();
 
@@ -199,7 +199,7 @@ mod value {
     }
 
     #[test]
-    fn interpret_option() {
+    fn option() {
         let result = interpret("x <option(int)> = some(1); x").unwrap();
 
         assert_eq!(Value::Option(Some(Box::new(Value::Integer(1)))), result);
@@ -210,11 +210,11 @@ mod function_call {
     use dust_lang::*;
 
     #[test]
-    fn interpret_function_call() {
+    fn function_call() {
         assert_eq!(
             interpret(
                 "
-                foobar = (message <str>) -> <str> { message }
+                foobar = (message <str>) <str> { message }
                 foobar('Hiya')
                 ",
             ),
@@ -223,7 +223,20 @@ mod function_call {
     }
 
     #[test]
-    fn interpret_callback() {
+    fn call_empty_function() {
+        assert_eq!(
+            interpret(
+                "
+                foobar = (message <str>) <none> {}
+                foobar('Hiya')
+                ",
+            ),
+            Ok(Value::none())
+        );
+    }
+
+    #[test]
+    fn callback() {
         assert_eq!(
             interpret(
                 "
@@ -238,7 +251,7 @@ mod function_call {
     }
 
     #[test]
-    fn interpret_built_in_function_call() {
+    fn built_in_function_call() {
         assert_eq!(interpret("output('Hiya')"), Ok(Value::Option(None)));
     }
 }
@@ -247,7 +260,7 @@ mod if_else {
     use dust_lang::*;
 
     #[test]
-    fn interpret_if() {
+    fn r#if() {
         assert_eq!(
             interpret("if true { 'true' }"),
             Ok(Value::String("true".to_string()))
@@ -255,7 +268,7 @@ mod if_else {
     }
 
     #[test]
-    fn interpret_if_else() {
+    fn if_else() {
         assert_eq!(
             interpret("if false { 1 } else { 2 }"),
             Ok(Value::Integer(2))
@@ -267,7 +280,7 @@ mod if_else {
     }
 
     #[test]
-    fn interpret_if_else_else_if_else() {
+    fn if_else_else_if_else() {
         assert_eq!(
             interpret(
                 "
@@ -285,7 +298,7 @@ mod if_else {
     }
 
     #[test]
-    fn interpret_if_else_if_else_if_else_if_else() {
+    fn if_else_if_else_if_else_if_else() {
         assert_eq!(
             interpret(
                 "
@@ -329,13 +342,13 @@ mod index {
         let test = interpret(
             "
             x = [1 2 3]
-            y = () -> <int> { 0 }
+            y = () <int> { 2 }
             x:y()
             ",
         )
         .unwrap();
 
-        assert_eq!(Value::Integer(1), test);
+        assert_eq!(Value::Integer(3), test);
     }
 }
 
@@ -343,7 +356,7 @@ mod r#match {
     use dust_lang::*;
 
     #[test]
-    fn interpret_match() {
+    fn r#match() {
         let test = interpret(
             "
                 match 1 {
@@ -359,7 +372,7 @@ mod r#match {
     }
 
     #[test]
-    fn interpret_match_assignment() {
+    fn match_assignment() {
         let test = interpret(
             "
                 x = match 1 {
@@ -380,7 +393,7 @@ mod r#while {
     use dust_lang::*;
 
     #[test]
-    fn interpret_while_loop() {
+    fn while_loop() {
         assert_eq!(interpret("while false { 'foo' }"), Ok(Value::Option(None)))
     }
 
@@ -428,19 +441,4 @@ mod type_definition {
             },
         }));
     }
-
-    #[test]
-    fn modify_value_async() {
-        let result = interpret(
-            "
-            fn = (x <int>) <none> {
-                
-            }
-
-            fn(1)
-            ",
-        );
-
-        assert_eq!(Ok(Value::none()), result);
-    }
 }

tree-sitter-dust/corpus/functions.txt

@@ -2,7 +2,7 @@
 Anonymous Function
 ================================================================================
 
-() <str> { "Hiya" }
+() -> <str> { "Hiya" }
 
 --------------------------------------------------------------------------------
 

tree-sitter-dust/grammar.js

@@ -11,14 +11,6 @@ module.exports = grammar({
 
     _comment: $ => /[#][^#\n]*[#|\n]/,
 
-    block: $ =>
-      seq(
-        optional('async'),
-        '{',
-        repeat1($.statement),
-        '}',
-      ),
-
     statement: $ =>
       prec.left(
         seq(
@@ -70,6 +62,14 @@ module.exports = grammar({
         ),
       ),
 
+    block: $ =>
+      seq(
+        optional('async'),
+        '{',
+        repeat($.statement),
+        '}',
+      ),
+
     identifier: $ =>
       choice(
         $._identifier_pattern,
@@ -175,7 +175,7 @@ module.exports = grammar({
     map: $ =>
       seq(
         '{',
-        repeat(
+        repeat1(
           seq(
             $.identifier,
             optional($.type_definition),

tree-sitter-dust/src/grammar.json

@@ -17,38 +17,6 @@
       "type": "PATTERN",
       "value": "[#][^#\\n]*[#|\\n]"
     },
-    "block": {
-      "type": "SEQ",
-      "members": [
-        {
-          "type": "CHOICE",
-          "members": [
-            {
-              "type": "STRING",
-              "value": "async"
-            },
-            {
-              "type": "BLANK"
-            }
-          ]
-        },
-        {
-          "type": "STRING",
-          "value": "{"
-        },
-        {
-          "type": "REPEAT1",
-          "content": {
-            "type": "SYMBOL",
-            "name": "statement"
-          }
-        },
-        {
-          "type": "STRING",
-          "value": "}"
-        }
-      ]
-    },
     "statement": {
       "type": "PREC_LEFT",
       "value": 0,
@@ -202,6 +170,38 @@
         }
       }
     },
+    "block": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "CHOICE",
+          "members": [
+            {
+              "type": "STRING",
+              "value": "async"
+            },
+            {
+              "type": "BLANK"
+            }
+          ]
+        },
+        {
+          "type": "STRING",
+          "value": "{"
+        },
+        {
+          "type": "REPEAT",
+          "content": {
+            "type": "SYMBOL",
+            "name": "statement"
+          }
+        },
+        {
+          "type": "STRING",
+          "value": "}"
+        }
+      ]
+    },
     "identifier": {
       "type": "CHOICE",
       "members": [
@@ -518,7 +518,7 @@
           "value": "{"
         },
         {
-          "type": "REPEAT",
+          "type": "REPEAT1",
           "content": {
             "type": "SEQ",
             "members": [

tree-sitter-dust/src/node-types.json

@@ -37,7 +37,7 @@
     "fields": {},
     "children": {
       "multiple": true,
-      "required": true,
+      "required": false,
       "types": [
         {
           "type": "statement",
@@ -365,7 +365,7 @@
     "fields": {},
     "children": {
       "multiple": true,
-      "required": false,
+      "required": true,
       "types": [
         {
           "type": "identifier",