added basic tests

mers/tests/return_true.mers

@@ -0,0 +1 @@
+true

mers/tests/test_in_mers.rs

@@ -0,0 +1,24 @@
+use std::{fs, path::Path};
+
+use mers_libs::file::File;
+use mers_libs::{parse, VDataEnum};
+
+#[test]
+fn run_all() {
+    for file in fs::read_dir(Path::new(file!()).parent().unwrap())
+        .unwrap()
+        .filter_map(|v| v.ok())
+    {
+        if let Some(file_name) = file.file_name().to_str() {
+            if file_name.ends_with(".mers") {
+                eprintln!("Checking {}", file_name);
+                let mut file = File::new(fs::read_to_string(file.path()).unwrap(), file.path());
+                // has to return true, otherwise the test will fail
+                assert!(matches!(
+                    parse::parse(&mut file).unwrap().run(vec![]).data,
+                    VDataEnum::Bool(true)
+                ));
+            }
+        }
+    }
+}

mers/tests/type_syntax.mers

@@ -0,0 +1,3 @@
+var: [string ...] = [...]
+&var.push("a string")
+var.len().eq(1)