From cce4ba9c2f421349e697e5af8229be7211512a60 Mon Sep 17 00:00:00 2001
From: Brendan Hansen <brendan.f.hansen@gmail.com>
Date: Thu, 30 Dec 2021 13:08:14 -0600
Subject: [PATCH] added 'did you mean ..' to unresolved symbol errors

---
 include/utils.h |  1 +
 src/symres.c    |  9 +++++++--
 src/utils.c     | 18 ++++++++++++++++++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/include/utils.h b/include/utils.h
index edba6c78..beb916f7 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -34,6 +34,7 @@ u32 char_to_base16_value(char x);
 i32 string_process_escape_seqs(char* dest, char* src, i32 len);
 
 u32 levenshtein_distance(const char *str1, const char *str2);
+char *find_closest_symbol_in_scope_and_parents(Scope *scope, char *sym);
 char *find_closest_symbol_in_node(AstNode *node, char *sym);
 
 extern AstTyped node_that_signals_a_yield;
diff --git a/src/symres.c b/src/symres.c
index 84e5ff43..e5c2a340 100644
--- a/src/symres.c
+++ b/src/symres.c
@@ -76,10 +76,15 @@ static SymresStatus symres_symbol(AstNode** symbol_node) {
 
     if (!res) { // :SymresStall
         if (report_unresolved_symbols) {
+            token_toggle_end(token);
+            char *closest = find_closest_symbol_in_scope_and_parents(curr_scope, token->text);
+            token_toggle_end(token);
+
             onyx_report_error(token->pos,
-                "Unable to resolve symbol '%b'",
+                "Unable to resolve symbol '%b'. Did you mean '%s'?",
                 token->text,
-                token->length);
+                token->length,
+                closest);
 
             return Symres_Error;
         } else {
diff --git a/src/utils.c b/src/utils.c
index d23ccb1c..898d29b0 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -997,6 +997,24 @@ char *find_closest_symbol_in_scope(Scope *scope, char *sym, u32 *out_distance) {
 
     return closest;
 }
+
+char *find_closest_symbol_in_scope_and_parents(Scope *scope, char *sym) {
+    u32 min_dist = 0x7fffffff;
+    u32 tmp_dist; 
+
+    char *closest = NULL;
+    while (scope != NULL) {
+        char *tmp_closest = find_closest_symbol_in_scope(scope, sym, &tmp_dist);
+        if (tmp_dist < min_dist) {
+            min_dist = tmp_dist;
+            closest = tmp_closest;
+        }
+
+        scope = scope->parent;
+    }
+
+    return closest;
+}
         
 char *find_closest_symbol_in_node(AstNode* node, char *sym) {
     b32 used_pointer = 0;
-- 
2.25.1