adding proper unit testing

test/root.zig

@@ -0,0 +1,43 @@
+const std = @import("std");
+const spv = @import("spv");
+const nzsl = @import("nzsl");
+
+pub fn compileNzsl(allocator: std.mem.Allocator, source: []const u8) ![]const u32 {
+    const module = try nzsl.parser.parseSource(source);
+    defer module.deinit();
+
+    const params = try nzsl.BackendParameters.init();
+    defer params.deinit();
+    params.setDebugLevel(.full);
+
+    const writer = try nzsl.SpirvWriter.init();
+    defer writer.deinit();
+
+    const output = try writer.generate(module, params);
+    defer output.deinit();
+
+    return allocator.dupe(u32, output.getCode());
+}
+
+pub const case = struct {
+    pub fn expectOutput(comptime T: type, source: []const u32, output_name: []const u8, comptime expected: []const T) !void {
+        const allocator = std.testing.allocator;
+
+        var module = try spv.Module.init(allocator, source);
+        defer module.deinit(allocator);
+
+        var rt = try spv.Runtime.init(allocator, &module);
+        defer rt.deinit(allocator);
+
+        try rt.callEntryPoint(allocator, try rt.getEntryPointByName("main"));
+        var output: [expected.len]T = undefined;
+        try rt.readOutput(T, output[0..output.len], try rt.getResultByName(output_name));
+
+        try std.testing.expectEqualSlices(T, expected, &output);
+    }
+};
+
+test {
+    std.testing.refAllDecls(@import("basics.zig"));
+    std.testing.refAllDecls(@import("maths.zig"));
+}