test: write custom test harness for tests

3 files changed, 695 insertions, 2 deletions

diff --git a/dhall/Cargo.toml b/dhall/Cargo.toml
index 9a30d24..ecb68eb 100644
--- a/dhall/Cargo.toml
+++ b/dhall/Cargo.toml
@@ -11,6 +11,10 @@ edition = "2018"
 build = "build.rs"
 include = ["src/**/*", "README.md", "build.rs"]
 
+[[test]]
+name = "spec"
+harness = false
+
 [dependencies]
 annotate-snippets = "0.7.0"
 hex = "0.4.2"
@@ -31,9 +35,12 @@ url = "2.1"
 reqwest = { version = "0.10", features = ["blocking"] }
 
 [dev-dependencies]
+# Latest master allows tests to be run in parallel.
+libtest-mimic = { version = "0.2.0", git = "https://github.com/LukasKalbertodt/libtest-mimic" }
 pretty_assertions = "0.6.1"
-version-sync = "0.9"
 rand = "0.7"
+version-sync = "0.9"
+walkdir = "2"
 
 [build-dependencies]
 walkdir = "2"
diff --git a/dhall/src/tests.rs b/dhall/src/tests.rs
index 08a4a4a..c9ba377 100644
--- a/dhall/src/tests.rs
+++ b/dhall/src/tests.rs
@@ -356,5 +356,5 @@ mod spec {
     }
 
     // See build.rs
-    include!(concat!(env!("OUT_DIR"), "/spec_tests.rs"));
+    // include!(concat!(env!("OUT_DIR"), "/spec_tests.rs"));
 }
diff --git a/dhall/tests/spec.rs b/dhall/tests/spec.rs
new file mode 100644
index 0000000..3521f6a
--- /dev/null
+++ b/dhall/tests/spec.rs
@@ -0,0 +1,686 @@
+use std::env;
+use std::ffi::OsString;
+use std::fs::{create_dir_all, read_to_string, File};
+use std::io::{Read, BufRead, BufReader, Write};
+use std::path::{Path, PathBuf};
+use std::rc::Rc;
+use std::fmt::Display;
+
+use walkdir::WalkDir;
+use libtest_mimic::{Arguments, Outcome, Test, run_tests};
+#[cfg(not(test))]
+use assert_eq as assert_eq_pretty;
+#[cfg(test)]
+use pretty_assertions::assert_eq as assert_eq_pretty;
+
+use dhall::error::{ErrorKind, Result};
+use dhall::syntax::{binary, Expr};
+use dhall::{Normalized, Parsed, Resolved, Typed};
+
+macro_rules! assert_eq_display {
+    ($left:expr, $right:expr) => {{
+        match (&$left, &$right) {
+            (left_val, right_val) => {
+                if !(*left_val == *right_val) {
+                    panic!(
+                        r#"assertion failed: `(left == right)`
+ left: `{}`,
+right: `{}`"#,
+                        left_val, right_val
+                    )
+                }
+            }
+        }
+    }};
+}
+
+/// Wrapper around string slice that makes debug output `{:?}` to print string same way as `{}`.
+/// Used in different `assert*!` macros in combination with `pretty_assertions` crate to make
+/// test failures to show nice diffs.
+#[derive(PartialEq, Eq)]
+#[doc(hidden)]
+pub struct PrettyString(String);
+
+/// Make diff to display string as multi-line string
+impl std::fmt::Debug for PrettyString {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        f.write_str(&self.0)
+    }
+}
+
+macro_rules! assert_eq_pretty_str {
+    ($left:expr, $right:expr) => {
+        assert_eq_pretty!(
+            PrettyString($left.to_string()),
+            PrettyString($right.to_string())
+        );
+    };
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+enum FileType {
+    /// Dhall source file
+    Text,
+    /// Dhall binary file
+    Binary,
+    /// Text file with hash
+    Hash,
+    /// Text file with expected text output
+    UI,
+}
+
+#[derive(Clone)]
+enum TestFile {
+    Source(String),
+    Binary(String),
+    UI(String),
+}
+
+impl FileType {
+    fn to_ext(self) -> &'static str {
+        match self {
+            FileType::Text => "dhall",
+            FileType::Binary => "dhallb",
+            FileType::Hash => "hash",
+            FileType::UI => "txt",
+        }
+    }
+    fn constructor(self) -> &'static str {
+        match self {
+            FileType::Text => "TestFile::Source",
+            FileType::Binary => "TestFile::Binary",
+            FileType::Hash => "TestFile::Binary",
+            FileType::UI => "TestFile::UI",
+        }
+    }
+    fn construct(self, path: &str) -> TestFile {
+        match self {
+            FileType::Text => TestFile::Source(format!("{}.{}", path, self.to_ext())),
+            FileType::Binary => TestFile::Binary(format!("{}.{}", path, self.to_ext())),
+            FileType::Hash => TestFile::Binary(format!("{}.{}", path, self.to_ext())),
+            FileType::UI => TestFile::UI(format!("{}.{}", path, self.to_ext())),
+        }
+    }
+}
+
+impl TestFile {
+    pub fn path(&self) -> PathBuf {
+        match self {
+            TestFile::Source(path)
+            | TestFile::Binary(path)
+            | TestFile::UI(path) => PathBuf::from("dhall").join(path),
+        }
+    }
+
+    /// Parse the target file
+    pub fn parse(&self) -> Result<Parsed> {
+        match self {
+            TestFile::Source(_) => Parsed::parse_file(&self.path()),
+            TestFile::Binary(_) => Parsed::parse_binary_file(&self.path()),
+            TestFile::UI(_) => panic!("Can't parse a UI test file"),
+        }
+    }
+    /// Parse and resolve the target file
+    pub fn resolve(&self) -> Result<Resolved> {
+        Ok(self.parse()?.resolve()?)
+    }
+    /// Parse, resolve and tck the target file
+    pub fn typecheck(&self) -> Result<Typed> {
+        Ok(self.resolve()?.typecheck()?)
+    }
+    /// Parse, resolve, tck and normalize the target file
+    pub fn normalize(&self) -> Result<Normalized> {
+        Ok(self.typecheck()?.normalize())
+    }
+
+    /// If UPDATE_TEST_FILES=1, we overwrite the output files with our own output.
+    fn force_update() -> bool {
+        env::var("UPDATE_TEST_FILES") == Ok("1".to_string())
+    }
+    /// Write the provided expression to the pointed file.
+    fn write_expr(&self, expr: impl Into<Expr>) -> Result<()> {
+        let expr = expr.into();
+        let path = self.path();
+        create_dir_all(path.parent().unwrap())?;
+        let mut file = File::create(path)?;
+        match self {
+            TestFile::Source(_) => {
+                writeln!(file, "{}", expr)?;
+            }
+            TestFile::Binary(_) => {
+                let expr_data = binary::encode(&expr)?;
+                file.write_all(&expr_data)?;
+            }
+            TestFile::UI(_) => panic!("Can't write an expression to a UI file"),
+        }
+        Ok(())
+    }
+    /// Write the provided string to the pointed file.
+    fn write_ui(&self, x: impl Display) -> Result<()> {
+        match self {
+            TestFile::UI(_) => {}
+            _ => panic!("Can't write a ui string to a dhall file"),
+        }
+        let path = self.path();
+        create_dir_all(path.parent().unwrap())?;
+        let mut file = File::create(path)?;
+        writeln!(file, "{}", x)?;
+        Ok(())
+    }
+
+    /// Check that the provided expression matches the file contents.
+    pub fn compare(&self, expr: impl Into<Expr>) -> Result<()> {
+        let expr = expr.into();
+        if !self.path().is_file() {
+            return self.write_expr(expr);
+        }
+
+        let expected = self.parse()?.to_expr();
+        if expr != expected {
+            if Self::force_update() {
+                self.write_expr(expr)?;
+            } else {
+                assert_eq_display!(expr, expected);
+            }
+        }
+        Ok(())
+    }
+    /// Check that the provided expression matches the file contents.
+    pub fn compare_debug(&self, expr: impl Into<Expr>) -> Result<()> {
+        let expr = expr.into();
+        if !self.path().is_file() {
+            return self.write_expr(expr);
+        }
+
+        let expected = self.parse()?.to_expr();
+        if expr != expected {
+            if Self::force_update() {
+                self.write_expr(expr)?;
+            } else {
+                assert_eq_pretty!(expr, expected);
+            }
+        }
+        Ok(())
+    }
+    /// Check that the provided expression matches the file contents.
+    pub fn compare_binary(&self, expr: impl Into<Expr>) -> Result<()> {
+        let expr = expr.into();
+        match self {
+            TestFile::Binary(_) => {}
+            _ => panic!("This is not a binary file"),
+        }
+        if !self.path().is_file() {
+            return self.write_expr(expr);
+        }
+
+        let expr_data = binary::encode(&expr)?;
+        let expected_data = {
+            let mut data = Vec::new();
+            File::open(&self.path())?.read_to_end(&mut data)?;
+            data
+        };
+
+        // Compare bit-by-bit
+        if expr_data != expected_data {
+            if Self::force_update() {
+                self.write_expr(expr)?;
+            } else {
+                use serde_cbor::de::from_slice;
+                use serde_cbor::value::Value;
+                // Pretty-print difference
+                assert_eq_pretty!(
+                    from_slice::<Value>(&expr_data).unwrap(),
+                    from_slice::<Value>(&expected_data).unwrap()
+                );
+                // If difference was not visible in the cbor::Nir, compare normally.
+                assert_eq!(expr_data, expected_data);
+            }
+        }
+        Ok(())
+    }
+    /// Check that the provided string matches the file contents. Writes to the corresponding file
+    /// if it is missing.
+    pub fn compare_ui(&self, x: impl Display) -> Result<()> {
+        if !self.path().is_file() {
+            return self.write_ui(x);
+        }
+
+        let expected = read_to_string(self.path())?;
+        let msg = format!("{}\n", x);
+        if msg != expected {
+            if Self::force_update() {
+                self.write_ui(x)?;
+            } else {
+                assert_eq_pretty_str!(expected, msg);
+            }
+        }
+        Ok(())
+    }
+}
+
+#[derive(Clone)]
+struct TestFeature {
+    /// Name of the module, used in the output of `cargo test`
+    module_name: &'static str,
+    /// Directory containing the tests files, relative to the base tests directory
+    directory: &'static str,
+    /// Relevant variant of `dhall::tests::Test`
+    variant: Rc<dyn Fn(TestFile, TestFile) -> SpecTest>,
+    /// Given a file name, whether to only include it in release tests
+    too_slow_path: Rc<dyn Fn(&str) -> bool>,
+    /// Given a file name, whether to exclude it
+    exclude_path: Rc<dyn Fn(&str) -> bool>,
+    /// Type of the input file
+    input_type: FileType,
+    /// Type of the output file, if any
+    output_type: Option<FileType>,
+}
+
+#[derive(Clone)]
+enum SpecTest {
+    ParserSuccess(TestFile, TestFile),
+    ParserFailure(TestFile, TestFile),
+    Printer(TestFile, TestFile),
+    BinaryEncoding(TestFile, TestFile),
+    BinaryDecodingSuccess(TestFile, TestFile),
+    BinaryDecodingFailure(TestFile, TestFile),
+    ImportSuccess(TestFile, TestFile),
+    ImportFailure(TestFile, TestFile),
+    SemanticHash(TestFile, TestFile),
+    TypeInferenceSuccess(TestFile, TestFile),
+    TypeInferenceFailure(TestFile, TestFile),
+    Normalization(TestFile, TestFile),
+    AlphaNormalization(TestFile, TestFile),
+}
+
+fn define_features() -> Vec<TestFeature> {
+    let default_feature = TestFeature {
+        module_name: "",
+        directory: "",
+        variant: Rc::new(|_, _| panic!()),
+        too_slow_path: Rc::new(|_path: &str| false),
+        exclude_path: Rc::new(|_path: &str| false),
+        input_type: FileType::Text,
+        output_type: None,
+    };
+
+    #[allow(clippy::nonminimal_bool)]
+    vec![
+        TestFeature {
+            module_name: "parser_success",
+            directory: "parser/success/",
+            variant: Rc::new(SpecTest::ParserSuccess),
+            too_slow_path: Rc::new(|path: &str| path == "largeExpression"),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // Pretty sure the test is incorrect
+                    || path == "unit/import/urls/quotedPathFakeUrlEncode"
+            }),
+            output_type: Some(FileType::Binary),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "parser_failure",
+            directory: "parser/failure/",
+            variant: Rc::new(SpecTest::ParserFailure),
+            output_type: Some(FileType::UI),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "printer",
+            directory: "parser/success/",
+            variant: Rc::new(SpecTest::Printer),
+            too_slow_path: Rc::new(|path: &str| path == "largeExpression"),
+            output_type: Some(FileType::UI),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_encoding",
+            directory: "parser/success/",
+            variant: Rc::new(SpecTest::BinaryEncoding),
+            too_slow_path: Rc::new(|path: &str| path == "largeExpression"),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // Pretty sure the test is incorrect
+                    || path == "unit/import/urls/quotedPathFakeUrlEncode"
+                    // See https://github.com/pyfisch/cbor/issues/109
+                    || path == "double"
+                    || path == "unit/DoubleLitExponentNoDot"
+                    || path == "unit/DoubleLitSecretelyInt"
+            }),
+            output_type: Some(FileType::Binary),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_decoding_success",
+            directory: "binary-decode/success/",
+            variant: Rc::new(SpecTest::BinaryDecodingSuccess),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // We don't support bignums
+                    || path == "unit/IntegerBigNegative"
+                    || path == "unit/IntegerBigPositive"
+                    || path == "unit/NaturalBig"
+            }),
+            input_type: FileType::Binary,
+            output_type: Some(FileType::Text),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_decoding_failure",
+            directory: "binary-decode/failure/",
+            variant: Rc::new(SpecTest::BinaryDecodingFailure),
+            input_type: FileType::Binary,
+            output_type: Some(FileType::UI),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "import_success",
+            directory: "import/success/",
+            variant: Rc::new(SpecTest::ImportSuccess),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // TODO: import hash
+                    || path == "hashFromCache"
+                    // TODO: the standard does not respect https://tools.ietf.org/html/rfc3986#section-5.2
+                    || path == "unit/asLocation/RemoteCanonicalize4"
+                    // TODO: import headers
+                    || path == "customHeaders"
+                    || path == "headerForwarding"
+                    || path == "noHeaderForwarding"
+            }),
+            output_type: Some(FileType::Text),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "import_failure",
+            directory: "import/failure/",
+            variant: Rc::new(SpecTest::ImportFailure),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // TODO: import headers
+                    || path == "customHeadersUsingBoundVariable"
+            }),
+            output_type: Some(FileType::UI),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "semantic_hash",
+            directory: "semantic-hash/success/",
+            variant: Rc::new(SpecTest::SemanticHash),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // We don't support bignums
+                    || path == "simple/integerToDouble"
+                    // See https://github.com/pyfisch/cbor/issues/109
+                    || path == "prelude/Integer/toDouble/0"
+                    || path == "prelude/Integer/toDouble/1"
+                    || path == "prelude/Natural/toDouble/0"
+            }),
+            output_type: Some(FileType::Hash),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "beta_normalize",
+            directory: "normalization/success/",
+            variant: Rc::new(SpecTest::Normalization),
+            too_slow_path: Rc::new(|path: &str| path == "remoteSystems"),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // Cannot typecheck
+                    || path == "unit/Sort"
+                    // We don't support bignums
+                    || path == "simple/integerToDouble"
+                    // TODO: fix Double/show
+                    || path == "prelude/JSON/number/1"
+            }),
+            output_type: Some(FileType::Text),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "alpha_normalize",
+            directory: "alpha-normalization/success/",
+            variant: Rc::new(SpecTest::AlphaNormalization),
+            exclude_path: Rc::new(|path: &str| {
+                // This test is designed to not typecheck
+                path == "unit/FunctionNestedBindingXXFree"
+            }),
+            output_type: Some(FileType::Text),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "type_inference_success",
+            directory: "type-inference/success/",
+            variant: Rc::new(SpecTest::TypeInferenceSuccess),
+            too_slow_path: Rc::new(|path: &str| path == "prelude"),
+            output_type: Some(FileType::Text),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "type_inference_failure",
+            directory: "type-inference/failure/",
+            variant: Rc::new(SpecTest::TypeInferenceFailure),
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // TODO: enable free variable checking
+                    || path == "unit/MergeHandlerFreeVar"
+            }),
+            output_type: Some(FileType::UI),
+            ..default_feature
+        },
+    ]
+}
+
+fn run_test_or_panic(test: &SpecTest) {
+    let res = if env::var("CI_GRCOV").is_ok() {
+        let test: SpecTest = test.clone();
+        // Augment stack size when running with 0 inlining to avoid overflows
+        std::thread::Builder::new()
+            .stack_size(128 * 1024 * 1024)
+            .spawn(move || run_test(&test))
+            .unwrap()
+            .join()
+            .unwrap()
+    } else {
+        run_test(test)
+    };
+    match res {
+        Ok(_) => {}
+        Err(e) => panic!(e.to_string()),
+    }
+}
+
+fn run_test(test: &SpecTest) -> Result<()> {
+    use self::SpecTest::*;
+    // Setup current directory to the root of the repository. Important for `as Location` tests.
+    env::set_current_dir(
+        PathBuf::from(env!("CARGO_MANIFEST_DIR")).parent().unwrap(),
+    )?;
+    // Set environment variable for import tests.
+    env::set_var("DHALL_TEST_VAR", "6 * 7");
+
+    match test {
+        ParserSuccess(expr, expected) => {
+            let expr = expr.parse()?;
+            // This exercices both parsing and binary decoding
+            expected.compare_debug(expr)?;
+        }
+        ParserFailure(expr, expected) => {
+            use std::io;
+            let err = expr.parse().unwrap_err();
+            match err.kind() {
+                ErrorKind::Parse(_) => {}
+                ErrorKind::IO(e) if e.kind() == io::ErrorKind::InvalidData => {}
+                e => panic!("Expected parse error, got: {:?}", e),
+            }
+            expected.compare_ui(err)?;
+        }
+        BinaryEncoding(expr, expected) => {
+            let expr = expr.parse()?;
+            expected.compare_binary(expr)?;
+        }
+        BinaryDecodingSuccess(expr, expected) => {
+            let expr = expr.parse()?;
+            expected.compare_debug(expr)?;
+        }
+        BinaryDecodingFailure(expr, expected) => {
+            let err = expr.parse().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        Printer(expr, expected) => {
+            let parsed = expr.parse()?;
+            // Round-trip pretty-printer
+            let reparsed = Parsed::parse_str(&parsed.to_string())?;
+            assert_eq!(reparsed, parsed);
+            expected.compare_ui(parsed)?;
+        }
+        ImportSuccess(expr, expected) => {
+            let expr = expr.normalize()?;
+            expected.compare(expr)?;
+        }
+        ImportFailure(expr, expected) => {
+            let err = expr.resolve().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        SemanticHash(expr, expected) => {
+            let expr = expr.normalize()?.to_expr_alpha();
+            let hash = hex::encode(expr.hash()?);
+            expected.compare_ui(format!("sha256:{}", hash))?;
+        }
+        TypeInferenceSuccess(expr, expected) => {
+            let ty = expr.typecheck()?.get_type()?;
+            expected.compare(ty)?;
+        }
+        TypeInferenceFailure(expr, expected) => {
+            let err = expr.typecheck().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        Normalization(expr, expected) => {
+            let expr = expr.normalize()?;
+            expected.compare(expr)?;
+        }
+        AlphaNormalization(expr, expected) => {
+            let expr = expr.normalize()?.to_expr_alpha();
+            expected.compare(expr)?;
+        }
+    }
+
+    Ok(())
+}
+
+fn dhall_files_in_dir<'a>(
+    dir: &'a Path,
+    take_ab_suffix: bool,
+    filetype: FileType,
+) -> impl Iterator<Item = (String, String)> + 'a {
+    WalkDir::new(dir)
+        .into_iter()
+        .filter_map(|e| e.ok())
+        .filter_map(move |path| {
+            let path = path.path().strip_prefix(dir).unwrap();
+            let ext = path.extension()?;
+            if *ext != OsString::from(filetype.to_ext()) {
+                return None;
+            }
+            let path = path.to_string_lossy();
+            let path = &path[..path.len() - 1 - ext.len()];
+            let path = if take_ab_suffix && &path[path.len() - 1..] != "A" {
+                return None;
+            } else if take_ab_suffix {
+                path[..path.len() - 1].to_owned()
+            } else {
+                path.to_owned()
+            };
+            // Transform path into a valid Rust identifier
+            let name = path.replace("/", "_").replace("-", "_");
+            Some((name, path))
+        })
+}
+
+fn make_test_module(
+    tests: &mut Vec<Test<SpecTest>>,
+    base_paths: &[&Path],
+    feature: TestFeature,
+) -> std::io::Result<()> {
+    let take_ab_suffix = feature.output_type.is_some()
+        && (feature.output_type != Some(FileType::UI)
+            || feature.module_name == "printer");
+    let input_suffix = if take_ab_suffix { "A" } else { "" };
+    let output_suffix = if take_ab_suffix { "B" } else { "" };
+
+    for base_path in base_paths {
+        let tests_dir = base_path.join(feature.directory);
+        for (name, path) in
+            dhall_files_in_dir(&tests_dir, take_ab_suffix, feature.input_type)
+        {
+            if (feature.exclude_path)(&path) {
+                continue;
+            }
+            if (feature.too_slow_path)(&path) {
+                #[cfg(debug_assertions)]
+                continue;
+            }
+            let path = tests_dir.join(path);
+            let path = path.to_string_lossy();
+
+            let input = feature
+                .input_type
+                .construct(&format!("{}{}", path, input_suffix));
+            let output = match feature.output_type {
+                None => None,
+                Some(output_type @ FileType::UI) => {
+                    // All ui outputs are in the local `tests/` directory.
+                    let path = PathBuf::from("tests/").join(
+                        PathBuf::from(path.as_ref())
+                            .strip_prefix(base_path)
+                            .unwrap(),
+                    );
+                    let path = path.to_str().unwrap();
+                    let output = output_type
+                        .construct(&format!("{}{}", path, output_suffix));
+                    Some(output)
+                }
+                Some(output_type) => {
+                    let output = output_type
+                        .construct(&format!("{}{}", path, output_suffix));
+                    Some(output)
+                }
+            };
+
+            let test = match output {
+                None => panic!(),
+                Some(output) => {
+                    (feature.variant)(input, output)
+                }
+            };
+            tests.push(Test {
+                name: format!("{}::{}", feature.module_name, name),
+                kind: "".into(),
+                is_ignored: false,
+                is_bench: false,
+                data: test,
+            });
+        }
+    }
+    Ok(())
+}
+
+fn generate_tests() -> Vec<Test<SpecTest>> {
+    let spec_tests_dirs =
+        vec![Path::new("../dhall-lang/tests/"), Path::new("tests/")];
+
+    let features = define_features();
+
+    let mut tests = Vec::new();
+    for feature in features {
+        make_test_module(&mut tests, &spec_tests_dirs, feature).unwrap();
+    }
+    tests
+}
+
+fn main() {
+    let tests = generate_tests();
+
+    let args = Arguments::from_args();
+    run_tests(&args, tests, |test| { run_test_or_panic(&test.data); Outcome::Passed }).exit();
+}