Unify `skip_resolve_expr` with normal resolution

8 files changed, 94 insertions, 40 deletions

diff --git a/dhall/src/builtins.rs b/dhall/src/builtins.rs
index 39cc4ef..123e03d 100644
--- a/dhall/src/builtins.rs
+++ b/dhall/src/builtins.rs
@@ -2,15 +2,13 @@ use std::collections::{BTreeMap, HashMap};
 use std::convert::TryInto;
 
 use crate::operations::{BinOp, OpKind};
-use crate::semantics::{
-    nze, skip_resolve_expr, typecheck, Hir, HirKind, Nir, NirKind, NzEnv,
-    VarEnv,
-};
+use crate::semantics::{nze, Hir, HirKind, Nir, NirKind, NzEnv, VarEnv};
 use crate::syntax::Const::Type;
 use crate::syntax::{
     Const, Expr, ExprKind, InterpolatedText, InterpolatedTextContents, Label,
     NaiveDouble, NumKind, Span, UnspannedExpr, V,
 };
+use crate::{Ctxt, Parsed};
 
 /// Built-ins
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
@@ -178,7 +176,7 @@ macro_rules! make_type {
     };
 }
 
-pub fn type_of_builtin<'cx>(b: Builtin) -> Hir<'cx> {
+pub fn type_of_builtin<'cx>(cx: Ctxt<'cx>, b: Builtin) -> Hir<'cx> {
     use Builtin::*;
     let expr = match b {
         Bool | Natural | Integer | Double | Text => make_type!(Type),
@@ -253,7 +251,10 @@ pub fn type_of_builtin<'cx>(b: Builtin) -> Hir<'cx> {
             forall (A: Type) -> Optional A
         ),
     };
-    skip_resolve_expr(&expr).unwrap()
+    Parsed::from_expr_without_imports(expr)
+        .resolve(cx)
+        .unwrap()
+        .0
 }
 
 // Ad-hoc macro to help construct closures
@@ -323,8 +324,12 @@ fn apply_builtin<'cx>(
         DoneAsIs,
     }
     let make_closure = |e| {
-        typecheck(cx, &skip_resolve_expr(&e).unwrap())
+        Parsed::from_expr_without_imports(e)
+            .resolve(cx)
+            .unwrap()
+            .typecheck(cx)
             .unwrap()
+            .as_hir()
             .eval(env.clone())
     };
 
diff --git a/dhall/src/lib.rs b/dhall/src/lib.rs
index 7f77334..c27b633 100644
--- a/dhall/src/lib.rs
+++ b/dhall/src/lib.rs
@@ -58,6 +58,11 @@ pub struct ToExprOptions {
 }
 
 impl Parsed {
+    /// Construct from an `Expr`. This `Expr` will have imports disabled.
+    pub fn from_expr_without_imports(e: Expr) -> Self {
+        Parsed(e, ImportLocation::dhall_code_without_imports())
+    }
+
     pub fn parse_file(f: &Path) -> Result<Parsed, Error> {
         parse::parse_file(f)
     }
@@ -78,8 +83,11 @@ impl Parsed {
     pub fn resolve<'cx>(self, cx: Ctxt<'cx>) -> Result<Resolved<'cx>, Error> {
         resolve::resolve(cx, self)
     }
-    pub fn skip_resolve<'cx>(self) -> Result<Resolved<'cx>, Error> {
-        resolve::skip_resolve(self)
+    pub fn skip_resolve<'cx>(
+        self,
+        cx: Ctxt<'cx>,
+    ) -> Result<Resolved<'cx>, Error> {
+        resolve::skip_resolve(cx, self)
     }
 
     /// Converts a value back to the corresponding AST expression.
@@ -122,6 +130,9 @@ impl<'cx> Typed<'cx> {
         self.hir.to_expr(cx, ToExprOptions { alpha: false })
     }
 
+    pub fn as_hir(&self) -> &Hir<'cx> {
+        &self.hir
+    }
     pub fn ty(&self) -> &Type<'cx> {
         &self.ty
     }
diff --git a/dhall/src/semantics/resolve/cache.rs b/dhall/src/semantics/resolve/cache.rs
index 9a5e835..1fc8dd3 100644
--- a/dhall/src/semantics/resolve/cache.rs
+++ b/dhall/src/semantics/resolve/cache.rs
@@ -94,7 +94,7 @@ fn read_cache_file<'cx>(
         }
     }
 
-    Ok(parse_binary(&data)?.skip_resolve()?.typecheck(cx)?)
+    Ok(parse_binary(&data)?.resolve(cx)?.typecheck(cx)?)
 }
 
 /// Write a file to the cache.
diff --git a/dhall/src/semantics/resolve/hir.rs b/dhall/src/semantics/resolve/hir.rs
index cfde47e..3e282b4 100644
--- a/dhall/src/semantics/resolve/hir.rs
+++ b/dhall/src/semantics/resolve/hir.rs
@@ -1,5 +1,5 @@
 use crate::error::TypeError;
-use crate::semantics::{type_with, NameEnv, Nir, NzEnv, Tir, TyEnv};
+use crate::semantics::{type_with, typecheck, NameEnv, Nir, NzEnv, Tir, TyEnv};
 use crate::syntax::{Expr, ExprKind, Span, V};
 use crate::{Ctxt, ImportId, ToExprOptions};
 
@@ -81,7 +81,7 @@ impl<'cx> Hir<'cx> {
         &'hir self,
         cx: Ctxt<'cx>,
     ) -> Result<Tir<'cx, 'hir>, TypeError> {
-        self.typecheck(&TyEnv::new(cx))
+        typecheck(cx, self)
     }
 
     /// Eval the Hir. It will actually get evaluated only as needed on demand.
diff --git a/dhall/src/semantics/resolve/resolve.rs b/dhall/src/semantics/resolve/resolve.rs
index 011ed45..e040cf4 100644
--- a/dhall/src/semantics/resolve/resolve.rs
+++ b/dhall/src/semantics/resolve/resolve.rs
@@ -29,8 +29,10 @@ enum ImportLocationKind {
     Remote(Url),
     /// Environment variable
     Env(String),
-    /// Data without a location
+    /// Data without a location; chaining will start from current directory.
     Missing,
+    /// Token to signal that thi sfile should contain no imports.
+    NoImport,
 }
 
 /// The location of some data.
@@ -101,6 +103,7 @@ impl ImportLocationKind {
                 url = url.join(&path.file_path.join("/"))?;
                 ImportLocationKind::Remote(url)
             }
+            ImportLocationKind::NoImport => unreachable!(),
         })
     }
 
@@ -120,6 +123,7 @@ impl ImportLocationKind {
             ImportLocationKind::Missing => {
                 return Err(ImportError::Missing.into())
             }
+            ImportLocationKind::NoImport => unreachable!(),
         })
     }
 
@@ -134,6 +138,7 @@ impl ImportLocationKind {
             ImportLocationKind::Missing => {
                 return Err(ImportError::Missing.into())
             }
+            ImportLocationKind::NoImport => unreachable!(),
         })
     }
 
@@ -149,6 +154,7 @@ impl ImportLocationKind {
                 ("Environment", Some(name.clone()))
             }
             ImportLocationKind::Missing => ("Missing", None),
+            ImportLocationKind::NoImport => unreachable!(),
         };
 
         let asloc_ty = make_aslocation_uniontype();
@@ -171,6 +177,12 @@ impl ImportLocation {
             mode: ImportMode::Code,
         }
     }
+    pub fn dhall_code_without_imports() -> Self {
+        ImportLocation {
+            kind: ImportLocationKind::NoImport,
+            mode: ImportMode::Code,
+        }
+    }
     pub fn local_dhall_code(path: PathBuf) -> Self {
         ImportLocation {
             kind: ImportLocationKind::Local(path),
@@ -191,6 +203,10 @@ impl ImportLocation {
     fn chain(&self, import: &Import) -> Result<ImportLocation, Error> {
         // Makes no sense to chain an import if the current file is not a dhall file.
         assert!(matches!(self.mode, ImportMode::Code));
+        if matches!(self.kind, ImportLocationKind::NoImport) {
+            Err(ImportError::UnexpectedImport(import.clone()))?;
+        }
+
         let kind = match &import.location {
             ImportTarget::Local(prefix, path) => {
                 self.kind.chain_local(*prefix, path)?
@@ -232,30 +248,37 @@ impl ImportLocation {
         env: &mut ImportEnv<'cx>,
         span: Span,
     ) -> Result<Typed<'cx>, Error> {
-        let (hir, ty) = match self.mode {
+        let cx = env.cx();
+        let typed = match self.mode {
             ImportMode::Code => {
                 let parsed = self.kind.fetch_dhall()?;
-                let typed =
-                    resolve_with_env(env, parsed)?.typecheck(env.cx())?;
-                let hir = typed.normalize(env.cx()).to_hir();
-                (hir, typed.ty)
+                let typed = resolve_with_env(env, parsed)?.typecheck(cx)?;
+                Typed {
+                    // TODO: manage to keep the Nir around. Will need fixing variables.
+                    hir: typed.normalize(cx).to_hir(),
+                    ty: typed.ty,
+                }
             }
             ImportMode::RawText => {
                 let text = self.kind.fetch_text()?;
-                let hir = Hir::new(
-                    HirKind::Expr(ExprKind::TextLit(text.into())),
-                    span,
-                );
-                (hir, Type::from_builtin(env.cx(), Builtin::Text))
+                Typed {
+                    hir: Hir::new(
+                        HirKind::Expr(ExprKind::TextLit(text.into())),
+                        span,
+                    ),
+                    ty: Type::from_builtin(cx, Builtin::Text),
+                }
             }
             ImportMode::Location => {
                 let expr = self.kind.to_location();
-                let hir = skip_resolve_expr(&expr)?;
-                let ty = hir.typecheck_noenv(env.cx())?.ty().clone();
-                (hir, ty)
+                Parsed::from_expr_without_imports(expr)
+                    .resolve(cx)
+                    .unwrap()
+                    .typecheck(cx)
+                    .unwrap()
             }
         };
-        Ok(Typed { hir, ty })
+        Ok(typed)
     }
 }
 
@@ -476,16 +499,12 @@ pub fn resolve<'cx>(
     resolve_with_env(&mut ImportEnv::new(cx), parsed)
 }
 
-pub fn skip_resolve_expr<'cx>(expr: &Expr) -> Result<Hir<'cx>, Error> {
-    traverse_resolve_expr(&mut NameEnv::new(), expr, &mut |import, _span| {
-        Err(ImportError::UnexpectedImport(import).into())
-    })
-}
-
-pub fn skip_resolve<'cx>(parsed: Parsed) -> Result<Resolved<'cx>, Error> {
-    let Parsed(expr, _) = parsed;
-    let resolved = skip_resolve_expr(&expr)?;
-    Ok(Resolved(resolved))
+pub fn skip_resolve<'cx>(
+    cx: Ctxt<'cx>,
+    parsed: Parsed,
+) -> Result<Resolved<'cx>, Error> {
+    let parsed = Parsed::from_expr_without_imports(parsed.0);
+    Ok(resolve(cx, parsed)?)
 }
 
 pub trait Canonicalize {
diff --git a/dhall/src/semantics/tck/typecheck.rs b/dhall/src/semantics/tck/typecheck.rs
index f47563e..5a44c9c 100644
--- a/dhall/src/semantics/tck/typecheck.rs
+++ b/dhall/src/semantics/tck/typecheck.rs
@@ -62,8 +62,8 @@ fn type_one_layer<'cx>(
             },
         ),
         ExprKind::Builtin(b) => {
-            let t_hir = type_of_builtin(b);
-            typecheck(env.cx(), &t_hir)?.eval_to_type(env)?
+            let t_hir = type_of_builtin(cx, b);
+            typecheck(cx, &t_hir)?.eval_to_type(env)?
         }
         ExprKind::TextLit(interpolated) => {
             let text_type = Type::from_builtin(cx, Builtin::Text);
diff --git a/serde_dhall/src/options/de.rs b/serde_dhall/src/options/de.rs
index fc8c6dc..30846a2 100644
--- a/serde_dhall/src/options/de.rs
+++ b/serde_dhall/src/options/de.rs
@@ -243,7 +243,7 @@ impl<'a, A> Deserializer<'a, A> {
             let resolved = if self.allow_imports {
                 parsed.resolve(cx)?
             } else {
-                parsed.skip_resolve()?
+                parsed.skip_resolve(cx)?
             };
             let typed = match &T::get_annot(self.annot) {
                 None => resolved.typecheck(cx)?,
diff --git a/serde_dhall/tests/serde.rs b/serde_dhall/tests/serde.rs
index 1181f72..fe0bffb 100644
--- a/serde_dhall/tests/serde.rs
+++ b/serde_dhall/tests/serde.rs
@@ -226,6 +226,25 @@ mod serde {
             Ok(true)
         );
     }
+
+    #[test]
+    fn test_import() {
+        assert_de(
+            "../dhall-lang/tests/parser/success/unit/BoolLitTrueA.dhall",
+            true,
+        );
+        assert_eq!(
+            serde_dhall::from_str(
+                "../dhall-lang/tests/parser/success/unit/BoolLitTrueA.dhall"
+            )
+            .imports(false)
+            .static_type_annotation()
+            .parse::<bool>()
+            .map_err(|e| e.to_string()),
+            Err("UnexpectedImport(Import { mode: Code, location: Local(Parent, FilePath { file_path: [\"dhall-lang\", \"tests\", \"parser\", \"success\", \"unit\", \"BoolLitTrueA.dhall\"] }), hash: None })".to_string())
+        );
+    }
+
     // TODO: test various builder configurations
     // In particular test cloning and reusing builder
 }