impl importing from package lib, file, directory, and star

ast/src/leo.pest

@@ -299,7 +299,7 @@ package_access = {
     | import_symbol
 }
 
-multiple_package_access = _{ "(" ~ NEWLINE* ~ package_access ~ ("," ~ NEWLINE* ~ package_access)* ~ NEWLINE* ~ ")"}
+multiple_package_access = _{ "(" ~ NEWLINE* ~ package_access ~ ("," ~ NEWLINE* ~ package_access)* ~ ","? ~ NEWLINE* ~ ")"}
 
 // Declared in imports/star.rs
 star = {"*"}

compiler/src/constraints/import/import_symbol.rs

@@ -8,7 +8,10 @@ use leo_ast::LeoParser;
 use leo_types::{ImportSymbol, Program, Span};
 
 use snarkos_models::curves::{Field, PrimeField};
-use std::fs::DirEntry;
+use std::{
+    ffi::OsString,
+    fs::{read_dir, DirEntry},
+};
 
 static LIBRARY_FILE: &str = "src/lib.leo";
 
@@ -27,7 +30,10 @@ fn parse_import_file(entry: &DirEntry, span: &Span) -> Result<Program, ImportErr
         file_path.push(LIBRARY_FILE);
 
         if !file_path.exists() {
-            return Err(ImportError::expected_file(file_name, span.clone()));
+            return Err(ImportError::expected_lib_file(
+                format!("{:?}", file_path.as_path()),
+                span.clone(),
+            ));
         }
     }
 
@@ -41,13 +47,35 @@ fn parse_import_file(entry: &DirEntry, span: &Span) -> Result<Program, ImportErr
 
 impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
     pub fn enforce_import_star(&mut self, scope: String, entry: &DirEntry, span: Span) -> Result<(), ImportError> {
-        let mut program = parse_import_file(entry, &span)?;
+        // import star from a file
+        if entry.path().is_file() {
+            // only parse `.leo` files
+            if let Some(extension) = entry.path().extension() {
+                if extension.eq(&OsString::from("leo")) {
+                    let mut program = parse_import_file(entry, &span)?;
 
-        // Use same namespace as calling function for imported symbols
-        program = program.name(scope);
+                    // Use same namespace as calling function for imported symbols
+                    program = program.name(scope);
 
-        // * -> import all imports, circuits, functions in the current scope
-        self.resolve_definitions(program)
+                    // * -> import all imports, circuits, functions in the current scope
+                    self.resolve_definitions(program)
+                } else {
+                    Ok(())
+                }
+            } else {
+                Ok(())
+            }
+        } else {
+            // import star for every file in the directory
+            for entry in read_dir(entry.path()).map_err(|error| ImportError::directory_error(error, span.clone()))? {
+                match entry {
+                    Ok(entry) => self.enforce_import_star(scope.clone(), &entry, span.clone())?,
+                    Err(error) => return Err(ImportError::directory_error(error, span.clone())),
+                }
+            }
+
+            Ok(())
+        }
     }
 
     pub fn enforce_import_symbol(

compiler/src/constraints/import/package.rs

@@ -31,14 +31,23 @@ impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
         }
     }
 
-    pub fn enforce_package(&mut self, scope: String, path: PathBuf, package: Package) -> Result<(), ImportError> {
+    pub fn enforce_package(&mut self, scope: String, mut path: PathBuf, package: Package) -> Result<(), ImportError> {
         let package_name = package.name;
 
-        // search for package name in local src directory
+        // search for package name in local directory
         let mut source_directory = path.clone();
         source_directory.push(SOURCE_DIRECTORY_NAME);
 
-        let entries = fs::read_dir(source_directory)
+        // search for package name in `imports` directory
+        let mut imports_directory = path.clone();
+        imports_directory.push(IMPORTS_DIRECTORY_NAME);
+
+        // read from local `src` directory or the current path
+        if source_directory.exists() {
+            path = source_directory
+        }
+
+        let entries = fs::read_dir(path)
             .map_err(|error| ImportError::directory_error(error, package_name.span.clone()))?
             .into_iter()
             .collect::<Result<Vec<_>, std::io::Error>>()
@@ -53,10 +62,6 @@ impl<F: Field + PrimeField, G: GroupType<F>> ConstrainedProgram<F, G> {
                 .eq(&package_name.name)
         });
 
-        // search for package name in imports directory
-        let mut imports_directory = path.clone();
-        imports_directory.push(IMPORTS_DIRECTORY_NAME);
-
         if imports_directory.exists() {
             let entries = fs::read_dir(imports_directory)
                 .map_err(|error| ImportError::directory_error(error, package_name.span.clone()))?

compiler/src/errors/constraints/import.rs

@@ -35,8 +35,11 @@ impl ImportError {
         Self::new_from_span(message, span)
     }
 
-    pub fn expected_file(entry: String, span: Span) -> Self {
-        let message = format!("cannot import symbol `{}` from directory `{}`", span.text, entry);
+    pub fn expected_lib_file(entry: String, span: Span) -> Self {
+        let message = format!(
+            "expected library file`{}` when looking for symbol `{}`",
+            entry, span.text
+        );
 
         Self::new_from_span(message, span)
     }

compiler/tests/import/imports/bar/.gitignore

@@ -0,0 +1 @@
+outputs/

compiler/tests/import/imports/bar/Leo.toml

@@ -0,0 +1,3 @@
+[package]
+name = "bar"
+version = "0.1.0"

compiler/tests/import/imports/bar/src/bat/bat.leo

@@ -0,0 +1,3 @@
+circuit Bat {
+    t: u32
+}

compiler/tests/import/imports/bar/src/baz.leo

@@ -0,0 +1,3 @@
+circuit Baz {
+    z: u32
+}

compiler/tests/import/imports/bar/src/lib.leo

@@ -0,0 +1,3 @@
+circuit Bar {
+    r: u32
+}

compiler/tests/import/imports/car/.gitignore

@@ -0,0 +1 @@
+outputs/

compiler/tests/import/imports/car/Leo.toml

@@ -0,0 +1,3 @@
+[package]
+name = "car"
+version = "0.1.0"

compiler/tests/import/imports/car/src/lib.leo

@@ -0,0 +1,3 @@
+circuit Car {
+    c: u32
+}

compiler/tests/import/many_import.leo

@@ -0,0 +1,25 @@
+import test_import.( // local import
+    Point,
+    foo,
+);
+
+import bar.( // imports directory import
+    Bar,
+    baz.Baz,
+    bat.bat.Bat,
+);
+
+import car.Car; // imports directory import
+
+function main() -> u32 {
+    // const point = Point { x: 1u32, y: 1u32 };
+    // const foo = foo();
+
+    const bar = Bar { r: 1u32 };
+    const bat = Bat { t: 1u32 };
+    const baz = Baz { z: 1u32 };
+
+    const car = Car { c: 1u32 };
+
+    return car.c
+}

compiler/tests/import/many_import_star.leo

@@ -0,0 +1,16 @@
+import test_import.*; // local import
+import bar.*; // imports directory import
+import car.*; // imports directory import
+
+function main() -> u32 {
+    const point = Point { x: 1u32, y: 1u32 };
+    const foo = foo();
+
+    const bar = Bar { r: 1u32 };
+    const bat = Bat { t: 1u32 };
+    const baz = Baz { z: 1u32 };
+
+    const car = Car { c: 1u32 };
+
+    return car.c
+}

compiler/tests/import/mod.rs

@@ -56,3 +56,26 @@ fn test_alias() {
 
     output_one(program);
 }
+
+// more complex tests
+#[test]
+#[ignore]
+fn test_many_import() {
+    let bytes = include_bytes!("many_import.leo");
+    let program = parse_program(bytes).unwrap();
+
+    set_local_dir();
+
+    output_one(program);
+}
+
+#[test]
+#[ignore]
+fn test_many_import_star() {
+    let bytes = include_bytes!("many_import_star.leo");
+    let program = parse_program(bytes).unwrap();
+
+    set_local_dir();
+
+    output_one(program);
+}

leo/files/lib.rs

@@ -46,8 +46,8 @@ impl LibFile {
     fn template(&self) -> String {
         format!(
             r#"// The '{}' lib function.
-circuit Circ {{
-    c: field
+circuit Foo {{
+    a: field
 }}
 "#,
             self.package_name