bug fixes and performance improvements

src/pipeline/error/not_exported.rs

@@ -0,0 +1,36 @@
+use std::rc::Rc;
+
+use crate::{utils::BoxedIter, representations::location::Location};
+
+use super::{ProjectError, ErrorPosition};
+
+#[derive(Debug)]
+pub struct NotExported {
+  pub file: Vec<String>,
+  pub subpath: Vec<String>,
+  pub referrer_file: Vec<String>,
+  pub referrer_subpath: Vec<String>,
+}
+impl ProjectError for NotExported {
+  fn description(&self) -> &str {
+    "An import refers to a symbol that exists but isn't exported"
+  }
+  fn positions(&self) -> BoxedIter<ErrorPosition> {
+    Box::new([
+      ErrorPosition{
+        location: Location::File(Rc::new(self.file.clone())),
+        message: Some(format!(
+          "{} isn't exported",
+          self.subpath.join("::")
+        )),
+      },
+      ErrorPosition{
+        location: Location::File(Rc::new(self.referrer_file.clone())),
+        message: Some(format!(
+          "{} cannot see this symbol",
+          self.referrer_subpath.join("::")
+        )),
+      }
+    ].into_iter())
+  }
+}