Merge pull request #170 from Nadrieril/custom-harness

1 files changed, 713 insertions, 0 deletions

diff --git a/dhall/tests/spec.rs b/dhall/tests/spec.rs
new file mode 100644
index 0000000..a423435
--- /dev/null
+++ b/dhall/tests/spec.rs
@@ -0,0 +1,713 @@
+use anyhow::Result;
+use std::env;
+use std::ffi::OsString;
+use std::fmt::{Debug, Display};
+use std::fs::{create_dir_all, read_to_string, File};
+use std::io::{Read, Write};
+use std::path::{Path, PathBuf};
+use std::rc::Rc;
+
+use libtest_mimic::{Arguments, Outcome, Test};
+use walkdir::WalkDir;
+
+use dhall::error::Error as DhallError;
+use dhall::error::ErrorKind;
+use dhall::syntax::{binary, Expr};
+use dhall::{Normalized, Parsed, Resolved, Typed};
+
+static LOCAL_TEST_PATH: &str = "tests/";
+static TEST_PATHS: &[&str] = &["../dhall-lang/tests/", LOCAL_TEST_PATH];
+
+#[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 construct(self, path: &str) -> TestFile {
+        let file = format!("{}.{}", path, self.to_ext());
+        match self {
+            FileType::Text => TestFile::Source(file),
+            FileType::Binary => TestFile::Binary(file),
+            FileType::Hash => TestFile::Binary(file),
+            FileType::UI => TestFile::UI(file),
+        }
+    }
+}
+
+// Custom assert_eq macro that returns an Error and prints pretty diffs.
+macro_rules! assert_eq {
+    (@@make_str, debug, $x:expr) => {
+        format!("{:#?}", $x)
+    };
+    (@@make_str, display, $x:expr) => {
+        $x.to_string()
+    };
+
+    (@$style:ident, $left:expr, $right:expr) => {
+        match (&$left, &$right) {
+            (left_val, right_val) => {
+                if *left_val != *right_val {
+                    let left_val = assert_eq!(@@make_str, $style, left_val);
+                    let right_val = assert_eq!(@@make_str, $style, right_val);
+                    let msg = format!(
+                        "assertion failed: `(left == right)`\n\n{}\n",
+                        colored_diff::PrettyDifference {
+                            expected: &left_val,
+                            actual: &right_val
+                        }
+                    );
+                    return Err(TestError(msg).into());
+                }
+            }
+        }
+    };
+    ($left:expr, $right:expr) => {
+        assert_eq!(@debug, $left, $right)
+    };
+}
+
+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> {
+        Ok(match self {
+            TestFile::Source(_) => Parsed::parse_file(&self.path())?,
+            TestFile::Binary(_) => Parsed::parse_binary_file(&self.path())?,
+            TestFile::UI(_) => {
+                Err(TestError(format!("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(_) => Err(TestError(format!(
+                "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(_) => {}
+            _ => Err(TestError(format!(
+                "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!(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(_) => {}
+            _ => Err(TestError(format!("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!(
+                    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 expected = expected.replace("\r\n", "\n"); // Normalize line endings
+        let msg = format!("{}\n", x);
+        // TODO: git changes newlines on windows
+        let msg = msg.replace("\r\n", "\n");
+        if msg != expected {
+            if Self::force_update() {
+                self.write_ui(x)?;
+            } else {
+                assert_eq!(@display, 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::SpecTestKind`
+    variant: SpecTestKind,
+    /// 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
+    output_type: FileType,
+}
+
+#[derive(Clone, Copy)]
+enum SpecTestKind {
+    ParserSuccess,
+    ParserFailure,
+    Printer,
+    BinaryEncoding,
+    BinaryDecodingSuccess,
+    BinaryDecodingFailure,
+    ImportSuccess,
+    ImportFailure,
+    SemanticHash,
+    TypeInferenceSuccess,
+    TypeInferenceFailure,
+    Normalization,
+    AlphaNormalization,
+}
+
+#[derive(Clone)]
+struct SpecTest {
+    kind: SpecTestKind,
+    input: TestFile,
+    output: TestFile,
+}
+
+#[derive(Debug, Clone)]
+struct TestError(String);
+
+impl std::fmt::Display for TestError {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{}", &self.0)
+    }
+}
+impl std::error::Error for TestError {}
+
+fn dhall_files_in_dir<'a>(
+    dir: &'a Path,
+    take_ab_suffix: bool,
+    filetype: FileType,
+) -> impl Iterator<Item = 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()
+            };
+            Some(path)
+        })
+}
+
+fn discover_tests_for_feature(feature: TestFeature) -> Vec<Test<SpecTest>> {
+    let take_ab_suffix =
+        feature.output_type != FileType::UI || feature.module_name == "printer";
+    let input_suffix = if take_ab_suffix { "A" } else { "" };
+    let output_suffix = if take_ab_suffix { "B" } else { "" };
+
+    let mut tests = Vec::new();
+    for base_path in TEST_PATHS {
+        let base_path = Path::new(base_path);
+        let tests_dir = base_path.join(feature.directory);
+        for path in
+            dhall_files_in_dir(&tests_dir, take_ab_suffix, feature.input_type)
+        {
+            let normalized_path = path.replace("\\", "/");
+            if (feature.exclude_path)(&normalized_path) {
+                continue;
+            }
+            if (feature.too_slow_path)(&normalized_path)
+                && cfg!(debug_assertions)
+            {
+                continue;
+            }
+            let path = tests_dir.join(path);
+            let path = path.to_string_lossy();
+
+            let output_path = match feature.output_type {
+                FileType::UI => {
+                    // All ui outputs are in the local tests directory.
+                    let path = PathBuf::from(LOCAL_TEST_PATH).join(
+                        PathBuf::from(path.as_ref())
+                            .strip_prefix(base_path)
+                            .unwrap(),
+                    );
+                    path.to_str().unwrap().to_owned()
+                }
+                _ => path.as_ref().to_owned(),
+            };
+
+            // Transform path into a valid Rust identifier
+            let name = normalized_path.replace("/", "_").replace("-", "_");
+            let input = feature
+                .input_type
+                .construct(&format!("{}{}", path, input_suffix));
+            let output = feature
+                .output_type
+                .construct(&format!("{}{}", output_path, output_suffix));
+
+            tests.push(Test {
+                name: format!("{}::{}", feature.module_name, name),
+                kind: "".into(),
+                is_ignored: false,
+                is_bench: false,
+                data: SpecTest {
+                    input,
+                    output,
+                    kind: feature.variant,
+                },
+            });
+        }
+    }
+    tests
+}
+
+fn define_features() -> Vec<TestFeature> {
+    let default_feature = TestFeature {
+        module_name: "",
+        directory: "",
+        variant: SpecTestKind::ParserSuccess, // Dummy
+        too_slow_path: Rc::new(|_path: &str| false),
+        exclude_path: Rc::new(|_path: &str| false),
+        input_type: FileType::Text,
+        output_type: FileType::Text,
+    };
+
+    #[allow(clippy::nonminimal_bool)]
+    vec![
+        TestFeature {
+            module_name: "parser_success",
+            directory: "parser/success/",
+            variant: SpecTestKind::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: FileType::Binary,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "parser_failure",
+            directory: "parser/failure/",
+            variant: SpecTestKind::ParserFailure,
+            output_type: FileType::UI,
+            exclude_path: Rc::new(|_path: &str| {
+                // TODO: git changes newlines on windows
+                cfg!(windows)
+            }),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "printer",
+            directory: "parser/success/",
+            variant: SpecTestKind::Printer,
+            too_slow_path: Rc::new(|path: &str| path == "largeExpression"),
+            output_type: FileType::UI,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_encoding",
+            directory: "parser/success/",
+            variant: SpecTestKind::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: FileType::Binary,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_decoding_success",
+            directory: "binary-decode/success/",
+            variant: SpecTestKind::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,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "binary_decoding_failure",
+            directory: "binary-decode/failure/",
+            variant: SpecTestKind::BinaryDecodingFailure,
+            input_type: FileType::Binary,
+            output_type: FileType::UI,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "import_success",
+            directory: "import/success/",
+            variant: SpecTestKind::ImportSuccess,
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // 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"
+                    // TODO: git changes newlines on windows
+                    || (cfg!(windows) && path == "unit/AsText")
+                    // TODO: paths on windows have backslashes; this breaks all the `as Location` tests
+                    // See https://github.com/dhall-lang/dhall-lang/issues/1032
+                    || (cfg!(windows) && path.contains("asLocation"))
+            }),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "import_failure",
+            directory: "import/failure/",
+            variant: SpecTestKind::ImportFailure,
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // TODO: paths on windows have backslashes; this breaks many things
+                    || cfg!(windows)
+                    // TODO: import headers
+                    || path == "customHeadersUsingBoundVariable"
+            }),
+            output_type: FileType::UI,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "semantic_hash",
+            directory: "semantic-hash/success/",
+            variant: SpecTestKind::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: FileType::Hash,
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "beta_normalize",
+            directory: "normalization/success/",
+            variant: SpecTestKind::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"
+            }),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "alpha_normalize",
+            directory: "alpha-normalization/success/",
+            variant: SpecTestKind::AlphaNormalization,
+            exclude_path: Rc::new(|path: &str| {
+                // This test is designed to not typecheck
+                path == "unit/FunctionNestedBindingXXFree"
+            }),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "type_inference_success",
+            directory: "type-inference/success/",
+            variant: SpecTestKind::TypeInferenceSuccess,
+            too_slow_path: Rc::new(|path: &str| path == "prelude"),
+            ..default_feature.clone()
+        },
+        TestFeature {
+            module_name: "type_inference_failure",
+            directory: "type-inference/failure/",
+            variant: SpecTestKind::TypeInferenceFailure,
+            exclude_path: Rc::new(|path: &str| {
+                false
+                    // TODO: enable free variable checking
+                    || path == "unit/MergeHandlerFreeVar"
+                    // TODO: git changes newlines on windows
+                    || cfg!(windows)
+            }),
+            output_type: FileType::UI,
+            ..default_feature
+        },
+    ]
+}
+
+fn run_test_stringy_error(test: &SpecTest) -> std::result::Result<(), String> {
+    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)
+    };
+    res.map_err(|e| e.to_string())
+}
+
+fn run_test(test: &SpecTest) -> Result<()> {
+    use self::SpecTestKind::*;
+    // Setup current directory to the root of the repository. Important for `as Location` tests.
+    let root_dir = PathBuf::from(env!("CARGO_MANIFEST_DIR"))
+        .parent()
+        .unwrap()
+        .to_path_buf();
+    env::set_current_dir(root_dir.as_path())?;
+    // Set environment variable for import tests.
+    env::set_var("DHALL_TEST_VAR", "6 * 7");
+
+    let SpecTest {
+        input: expr,
+        output: expected,
+        ..
+    } = test;
+    match test.kind {
+        ParserSuccess => {
+            let expr = expr.parse()?;
+            // This exercices both parsing and binary decoding
+            expected.compare_debug(expr)?;
+        }
+        ParserFailure => {
+            use std::io;
+            let err = expr.parse().unwrap_err();
+            match err.downcast_ref::<DhallError>() {
+                Some(err) => match err.kind() {
+                    ErrorKind::Parse(_) => {}
+                    ErrorKind::IO(e)
+                        if e.kind() == io::ErrorKind::InvalidData => {}
+                    e => Err(TestError(format!(
+                        "Expected parse error, got: {:?}",
+                        e
+                    )))?,
+                },
+                None => {}
+            }
+            expected.compare_ui(err)?;
+        }
+        BinaryEncoding => {
+            let expr = expr.parse()?;
+            expected.compare_binary(expr)?;
+        }
+        BinaryDecodingSuccess => {
+            let expr = expr.parse()?;
+            expected.compare_debug(expr)?;
+        }
+        BinaryDecodingFailure => {
+            let err = expr.parse().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        Printer => {
+            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 => {
+            // Configure cache for import tests
+            env::set_var(
+                "XDG_CACHE_HOME",
+                root_dir
+                    .join("dhall-lang")
+                    .join("tests")
+                    .join("import")
+                    .join("cache")
+                    .as_path(),
+            );
+            let expr = expr.normalize()?;
+            expected.compare(expr)?;
+        }
+        ImportFailure => {
+            let err = expr.resolve().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        SemanticHash => {
+            let expr = expr.normalize()?.to_expr_alpha();
+            let hash = hex::encode(expr.hash()?);
+            expected.compare_ui(format!("sha256:{}", hash))?;
+        }
+        TypeInferenceSuccess => {
+            let ty = expr.typecheck()?.get_type()?;
+            expected.compare(ty)?;
+        }
+        TypeInferenceFailure => {
+            let err = expr.typecheck().unwrap_err();
+            expected.compare_ui(err)?;
+        }
+        Normalization => {
+            let expr = expr.normalize()?;
+            expected.compare(expr)?;
+        }
+        AlphaNormalization => {
+            let expr = expr.normalize()?.to_expr_alpha();
+            expected.compare(expr)?;
+        }
+    }
+
+    Ok(())
+}
+
+fn main() {
+    let tests = define_features()
+        .into_iter()
+        .flat_map(discover_tests_for_feature)
+        .collect();
+
+    libtest_mimic::run_tests(&Arguments::from_args(), tests, |test| {
+        match run_test_stringy_error(&test.data) {
+            Ok(_) => Outcome::Passed,
+            Err(e) => Outcome::Failed { msg: Some(e) },
+        }
+    })
+    .exit();
+}