added a way to show the call stack of the functions

src/parser/parser.cpp

@@ -7,6 +7,7 @@
 #include "ast/expressions/prefix.hpp"
 #include "token/token.hpp"
 #include "token/type.hpp"
+#include "utils/tracer.hpp"
 
 #include <sstream>
 
@@ -108,6 +109,7 @@ namespace parser {
     }
 
     ast::expression* parser::parse_expression(precedence prec) {
+        // TRACE_FUNCTION;
         auto prefix_it = prefix_parse_fns.find(current.type);
         if (prefix_it == prefix_parse_fns.end()) {
             unkown_prefix_error(current);
@@ -166,6 +168,7 @@ namespace parser {
     }
 
     ast::expression_stmt* parser::parse_expression_stmt() {
+        // TRACE_FUNCTION;
         ast::expression_stmt* stmt = new ast::expression_stmt(current);
 
         stmt->expression = parse_expression();
@@ -216,10 +219,12 @@ namespace parser {
     };
 
     ast::expression* parser::parse_integer() {
+        // TRACE_FUNCTION;
         return new ast::integer_literal(current, std::stoi(current.literal));
     };
 
     ast::expression* parser::parse_prefix_expr() {
+        // TRACE_FUNCTION;
         ast::prefix_expr* ret = new ast::prefix_expr(current, current.literal);
         next_token();
         ret->right = parse_expression(precedence::PREFIX);
@@ -227,6 +232,7 @@ namespace parser {
     };
 
     ast::expression* parser::parse_infix_expr(ast::expression* left) {
+        // TRACE_FUNCTION;
         ast::infix_expr* ret =
             new ast::infix_expr(current, current.literal, left);
         precedence prec = precedence_for(current.type);

src/utils/tracer.hpp

@@ -0,0 +1,22 @@
+
+#include <iostream>
+#include <string>
+
+namespace {
+    struct FunctionTracer {
+        std::string name;
+        inline static int tab_counter = 0;
+
+        FunctionTracer(const std::string& func): name(func) {
+            std::cout << std::string(tab_counter++, '\t') << "BEGIN " << name
+                      << std::endl;
+        }
+
+        ~FunctionTracer() {
+            std::cout << std::string(--tab_counter, '\t') << "Exiting " << name
+                      << std::endl;
+        }
+    };
+} // namespace
+
+#define TRACE_FUNCTION FunctionTracer tracer(__FUNCTION__);

test/parser/expression.cpp

@@ -205,4 +205,11 @@ TEST_SUITE("Parser: expression") {
             CHECK(program->str() == t.expected);
         }
     }
+
+    TEST_CASE_FIXTURE(ParserFixture, "Test to see trace") {
+        setup("-1 * 2 - 3");
+        CHECK(program->str() == "(((-1) * 2) - 3)");
+        setup("-1 - 2 * 3");
+        CHECK(program->str() == "((-1) - (2 * 3))");
+    }
 }