Partway there in terms of implementing source map lookup

schala-lang/language/src/source_map.rs

@@ -3,10 +3,12 @@ use std::fmt;
 
 use crate::ast::ItemId;
 
+pub type LineNumber = usize;
+
 #[derive(Debug, Clone, Copy, PartialEq)]
 pub struct Location {
-  pub line_num: usize,
+  pub line_num: LineNumber,
-  pub char_num: usize
+  pub char_num: usize,
 }
 
 impl fmt::Display for Location {
@@ -27,4 +29,11 @@ impl SourceMap {
   pub fn add_location(&mut self, id: &ItemId, loc: Location) {
     self.map.insert(id.clone(), loc);
   }
+
+  pub fn lookup(&self, id: &ItemId) -> Option<Location> {
+    match self.map.get(id) {
+      Some(loc) => Some(loc.clone()),
+      None => None
+    }
+  }
 }

schala-lang/language/src/symbol_table.rs

@@ -5,6 +5,7 @@ use std::fmt;
 use std::fmt::Write;
 
 use crate::schala::SourceMapHandle;
+use crate::source_map::{SourceMap, LineNumber};
 use crate::ast;
 use crate::ast::{ItemId, TypeBody, TypeSingletonName, Signature, Statement, StatementKind};
 use crate::typechecking::TypeName;
@@ -27,7 +28,6 @@ mod symbol_trie;
 use symbol_trie::SymbolTrie;
 mod test;
 
-type LineNumber = u32;
 type SymbolTrackTable = HashMap<Rc<String>, LineNumber>;
 
 #[derive(PartialEq, Eq, Hash, Debug, Clone, PartialOrd, Ord)]
@@ -163,14 +163,18 @@ impl SymbolTable {
   fn add_symbols_from_scope<'a>(&'a mut self, statements: &Vec<Statement>, scope_name_stack: &mut Vec<ScopeSegment>) -> Result<(), String> {
     use self::ast::Declaration::*;
 
-    fn insert_and_check_duplicate_symbol(table: &mut SymbolTrackTable, name: &Rc<String>) -> Result<(), String> {
+    fn insert_and_check_duplicate_symbol(table: &mut SymbolTrackTable, name: &Rc<String>, id: &ItemId, source_map: &SourceMap) -> Result<(), String> {
       match table.entry(name.clone()) {
         Entry::Occupied(o) => {
-          let line_number = o.get(); //TODO make this actually work
+          let line_number = o.get();
           Err(format!("Duplicate definition: {}. It's already defined at {}", name, line_number))
         },
         Entry::Vacant(v) => {
-          let line_number = 0; //TODO should work
+          let line_number = if let Some(loc) = source_map.lookup(id) {
+            loc.line_num
+          } else {
+            0
+          };
           v.insert(line_number);
           Ok(())
         }
@@ -180,14 +184,14 @@ impl SymbolTable {
     let mut seen_identifiers: SymbolTrackTable = HashMap::new();
 
     for statement in statements.iter() {
-      if let Statement { kind: StatementKind::Declaration(decl), .. } = statement {
+      if let Statement { kind: StatementKind::Declaration(decl), id } = statement {
         match decl {
           FuncSig(ref signature) => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name)?;
+            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name, &id, &self.source_map_handle.borrow())?;
             self.add_function_signature(signature, scope_name_stack)?
           }
           FuncDecl(ref signature, ref body) => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name)?;
+            insert_and_check_duplicate_symbol(&mut seen_identifiers, &signature.name, &id, &self.source_map_handle.borrow())?;
             self.add_function_signature(signature, scope_name_stack)?;
             scope_name_stack.push(ScopeSegment{
               name: signature.name.clone(),
@@ -197,11 +201,11 @@ impl SymbolTable {
             output?
           },
           TypeDecl { name, body, mutable } => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, &name.name)?;
+            insert_and_check_duplicate_symbol(&mut seen_identifiers, &name.name, &id, &self.source_map_handle.borrow())?;
             self.add_type_decl(name, body, mutable, scope_name_stack)?
           },
           Binding { name, .. } => {
-            insert_and_check_duplicate_symbol(&mut seen_identifiers, name)?;
+            insert_and_check_duplicate_symbol(&mut seen_identifiers, name, &id, &self.source_map_handle.borrow())?;
             self.add_new_symbol(name, scope_name_stack, SymbolSpec::Binding);
           }
           _ => ()

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

@@ -46,7 +46,6 @@ fn no_duplicates() {
   let mut symbol_table = SymbolTable::new(source_map);
   let ast = quick_ast(source);
   let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
-  println!("OUTPUT: {}", output);
   assert!(output.contains("Duplicate"))
 }
 
@@ -61,6 +60,7 @@ fn no_duplicates_2() {
   let mut symbol_table = SymbolTable::new(source_map);
   let ast = quick_ast(source);
   let output = symbol_table.add_top_level_symbols(&ast).unwrap_err();
+  println!("OUTPUT: {}", output);
   assert!(output.contains("Duplicate"));
   assert!(output.contains("Line 3"));
 }