From 9390f4fd314530534542b232fd01378b8d517995 Mon Sep 17 00:00:00 2001
From: Riyyi <riyyi3@gmail.com>
Date: Fri, 22 Jul 2022 22:30:24 +0200
Subject: [PATCH] Util: Add custom assert

---
 src/util/meta/assert.h | 97 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)
 create mode 100644 src/util/meta/assert.h

diff --git a/src/util/meta/assert.h b/src/util/meta/assert.h
new file mode 100644
index 0000000..47689ec
--- /dev/null
+++ b/src/util/meta/assert.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2022 Riyyi
+ *
+ * SPDX-License-Identifier: MIT
+ */
+
+#pragma once
+
+#include <cstddef> // size_t
+#include <cstdint> // uint32_t
+#include <cstring> // strlen
+#include <fstream> // ifstream
+#include <string>
+
+#include "util/format/format.h"
+#include "util/meta/compiler.h"
+
+#define CRASH() asm volatile("int $0x03");
+
+#ifndef NDEBUG
+	#define VERIFY(expr, ...) (static_cast<bool>(expr) ? (void)0 : Util::__assertion_failed(#expr, __FILE__, __LINE__, FUNCTION_MACRO __VA_OPT__(, ) __VA_ARGS__))
+	#define VERIFY_NOT_REACHED() VERIFY(false)
+#else
+	#define VERIFY(expr, ...) (static_cast<bool>(expr) ? (void)0 : CRASH()
+	#define VERIFY_NOT_REACHED() CRASH()
+#endif
+
+#ifndef NDEBUG
+namespace Util {
+
+template<typename... Parameters>
+inline void __assertion_failed(const char* assertion, const char* file, uint32_t line, const char* function, const Parameters&... parameters)
+{
+	// Get the line that caused the error
+	std::ifstream source(file);
+	std::string content;
+	if (source.is_open()) {
+		for (uint32_t i = 0; std::getline(source, content); ++i) {
+			if (i == line - 1) {
+				break;
+			}
+		}
+	}
+	// Replace tab indentation with spaces
+	size_t tabs = content.find_first_not_of('\t');
+	if (tabs > 0 && tabs < content.size()) {
+		content = std::string(tabs * 4, ' ') + content.substr(tabs);
+	}
+
+	// Find the assertion in the line
+	size_t column = content.find(assertion);
+	size_t assertionLength = strlen(assertion);
+	if (column == std::string::npos) {
+		column = content.find_first_not_of(' ');
+		assertionLength = content.length() - column;
+	}
+
+	// Error message
+	fprintf(stderr,
+	        "\033[;1m%s:%u:%zu "
+	        "\033[31;1merror: "
+	        "\033[0massertion failed",
+	        file, line, column + 1);
+	if constexpr (sizeof...(Parameters) > 0) {
+		fprintf(stderr, ": ");
+		// Cant use the formatting library to print asserts caused by the formatting library
+		if (!std::string_view(function).starts_with("Util::Format::")) {
+			std::string message;
+			strln(message, parameters...);
+			fprintf(stderr, "%s", message.c_str());
+		}
+		else {
+			fprintf(stderr, parameters...);
+			fprintf(stderr, "\n");
+		}
+	}
+	else {
+		fprintf(stderr, "\n");
+	}
+
+	// Code line
+	fprintf(stderr, " %u | %s\033[31;1m%s\033[0m%s\n", line,
+	        content.substr(0, column).c_str(),                 // Whitespace at front
+	        content.substr(column, assertionLength).c_str(),   // Error portion
+	        content.substr(column + assertionLength).c_str()); // Rest of the line
+
+	// Arrow pointer
+	fprintf(stderr, " %s | %s\033[31;1m^%s\033[0m\n",
+	        std::string(std::to_string(line).length(), ' ').c_str(), // Line number spacing
+	        std::string(column, ' ').c_str(),                        // Content spacing
+	        std::string(assertionLength - 1, '~').c_str());          // Arrow pointer
+
+	CRASH();
+}
+
+} // namespace Util
+#endif