fix: replace unsafe fixed-size buffers with dynamic formatting helpers; add util format helpers; centralize log_on_line cleanup

v0/test.c

@@ -3,6 +3,7 @@
 #include <stdio.h>
 #include <string.h>
 #include <stdlib.h>
+#include "util.h"
 
 static jmp_buf s_testJmp;
 static const char* s_failMsg;
@@ -49,8 +50,11 @@ char* read_file_content(const char* filepath) {
 }
 
 void assert_log_file(const char* msg) {
-    char filepath[256];
-    snprintf(filepath, sizeof(filepath), "v0/tests/%s.log", s_currentTestName);
+    char* filepath = format_string("v0/tests/%s.log", s_currentTestName);
+    if (!filepath) {
+        fail("out of memory");
+        return;
+    }
 
     const char* generate = getenv("GENERATE_GOLDEN");
     if (generate && strcmp(generate, "1") == 0) {
@@ -67,18 +71,24 @@ void assert_log_file(const char* msg) {
     char* content = read_file_content(filepath);
     if (!content) {
         fail("could not open golden file for reading");
+        free(filepath);
         return;
     }
 
     assert_str(content, s_logOutput, msg);
     free(content);
+    free(filepath);
 }
 
 void assert_int(int expected, int actual, const char* msg) {
     if (expected != actual) {
-        char buf[64];
-        snprintf(buf, sizeof(buf), "%s (expected %d, got %d)", msg, expected, actual);
-        fail(buf);
+        char* buf = format_string("%s (expected %d, got %d)", msg, expected, actual);
+        if (buf) {
+            fail(buf);
+            free(buf);
+        } else {
+            fail("out of memory");
+        }
     }
 }
 
@@ -95,17 +105,22 @@ void assert_false(bool condition, const char* msg) {
 }
 
 TokenStream* tokenstream_get_test(void) {
-    char filepath[256];
-    snprintf(filepath, sizeof(filepath), "v0/tests/%s.c2", s_currentTestName);
+    char* filepath = format_string("v0/tests/%s.c2", s_currentTestName);
+    if (!filepath) {
+        fail("out of memory");
+        return NULL;
+    }
     
     if (s_testSource) free(s_testSource);
     s_testSource = read_file_content(filepath);
     if (!s_testSource) {
         fail("could not read test source file");
+        free(filepath);
         return NULL;
     }
-
-    return tokenstream_open(filepath, s_testSource);
+    TokenStream* ts = tokenstream_open(filepath, s_testSource);
+    free(filepath);
+    return ts;
 }
 
 static void log_append(const char* msg) {