3 files changed, 59 insertions, 0 deletions

diff --git a/tests/data/lexer/0001_hello.rs b/tests/data/lexer/0001_hello.rs
new file mode 100644
index 000000000..95d09f2b1
--- /dev/null
+++ b/tests/data/lexer/0001_hello.rs
@@ -0,0 +1 @@
+hello world
\ No newline at end of file
diff --git a/tests/data/lexer/0001_hello.txt b/tests/data/lexer/0001_hello.txt
new file mode 100644
index 000000000..5bec9be80
--- /dev/null
+++ b/tests/data/lexer/0001_hello.txt
@@ -0,0 +1,3 @@
+IDENT 5
+WHITESPACE 1
+IDENT 5
\ No newline at end of file
diff --git a/tests/lexer.rs b/tests/lexer.rs
new file mode 100644
index 000000000..de76f0a15
--- /dev/null
+++ b/tests/lexer.rs
@@ -0,0 +1,55 @@
+extern crate file;
+#[macro_use(assert_diff)]
+extern crate difference;
+
+use std::path::{PathBuf, Path};
+use std::fs::read_dir;
+
+#[test]
+fn lexer_tests() {
+    for test_case in lexer_test_cases() {
+        lexer_test_case(&test_case);
+    }
+}
+
+fn lexer_test_dir() -> PathBuf {
+    let dir = env!("CARGO_MANIFEST_DIR");
+    PathBuf::from(dir).join("tests/data/lexer")
+}
+
+fn lexer_test_cases() -> Vec<PathBuf> {
+    let mut acc = Vec::new();
+    let dir = lexer_test_dir();
+    for file in read_dir(&dir).unwrap() {
+        let file = file.unwrap();
+        let path = file.path();
+        if path.extension().unwrap_or_default() == "rs" {
+            acc.push(path);
+        }
+    }
+    acc
+}
+
+fn lexer_test_case(path: &Path) {
+    let actual = {
+        let text = file::get_text(path).unwrap();
+        let tokens = tokenize(&text);
+        dump_tokens(&tokens)
+    };
+    let expected = file::get_text(&path.with_extension("txt")).unwrap();
+
+    assert_diff!(
+        expected.as_str(),
+        actual.as_str(),
+        "\n",
+        0
+    )
+}
+
+fn tokenize(text: &str) -> Vec<()> {
+    Vec::new()
+}
+
+fn dump_tokens(tokens: &[()]) -> String {
+    "IDENT 5\nKEYWORD 1\nIDENT 5\n".to_string()
+}
\ No newline at end of file