Pretty print stack trace

src/errors.cpp

@@ -1,8 +1,10 @@
 #include <vector>
 #include <string>
+#include <iomanip>
 #include <iostream>
 using namespace std;
 
+#include "include/utils.h"
 #include "include/errors.h"
 #include "include/colors.h"
 #include "include/tokenize.h"
@@ -60,14 +62,26 @@ void print_error_position(vector<string> history, CodePosition pos) {
     if (pos.column == -1 || pos.line == -1)
         return;
 
-    cout << endl;
-    string line = history[pos.line];
-
-    printf(BOLD "%4d " RESET , pos.line+1);
-    cout << line << endl;
+    cout << endl << BOLD
+        << setw(4) << setfill(' ')
+        << pos.line+1 << " " RESET
+        << history[pos.line] << endl;
 
     for (int i=0; i < pos.column + 5; i++)
         cout << " ";
 
     cout << BOLD RED "^--" RESET << endl;
+}
+
+void print_error_stack_trace(vector<string> history, const RuntimeError& error) {
+    cout << "\n" BOLD "Traceback" RESET " (most recent call last)" << endl;
+    for (StackTraceEntry e : error.trace) {
+        cout << BOLD << setw(4) << setfill(' ')
+            << get<1>(e).line+1 << RESET BLUE
+            << setw(16) << setfill(' ')
+            << get<0>(e) << RESET << "\t"
+            << trim(history[get<1>(e).line]) << endl;
+    }
+
+    cout << BOLD RED "Runtime Error: " RESET << error.get_message() << endl;
 }

src/include/errors.h

@@ -115,4 +115,9 @@ public:
 */
 void print_error_position(vector<string> history, CodePosition pos);
 
+/**
+ * Display the stack trace associated with an error
+*/
+void print_error_stack_trace(vector<string> history, const RuntimeError& error);
+
 #endif

src/include/utils.h

@@ -39,4 +39,9 @@ string _debug_get_type_type_name(TypeType type);
 */
 bool equal_types(Type type1, Type type2);
 
+/**
+ * Trim a string (remove whitespaces before and after)
+*/
+string trim(const string& str);
+
 #endif

src/main.cpp

@@ -119,12 +119,7 @@ int main(int argc, char* argv[]) {
             cout << BOLD RED "Type Error: " RESET << e.get_message() << endl;
 
         } catch (const RuntimeError& e) {
-            print_error_position(input, e.pos);
-            cout << BOLD RED "Runtime Error: " RESET << e.get_message() << endl;
-
-            for (StackTraceEntry e : e.trace) {
-                cout << get<0>(e) << " " << (get<1>(e).line + 1) << endl;
-            }
+            print_error_stack_trace(input, e);
         }
         cout << endl;
     }

src/utils.cpp

@@ -111,4 +111,14 @@ bool equal_types(Type type1, Type type2) {
             return false;
         break;
     }
+}
+
+string trim(const string& str) {
+    size_t first = str.find_first_not_of(" \t\n\r");
+    size_t last = str.find_last_not_of(" \t\n\r");
+
+    if (first == string::npos || last == string::npos)
+        return ""; // or handle empty string
+
+    return str.substr(first, last - first + 1);
 }