Better error handling (fixes #15)

src/report.rs

@@ -1,6 +1,5 @@
 use std::borrow::Cow;
 use std::collections::HashMap;
-use std::process::ExitStatus;
 
 pub type Report = HashMap<String, bool>;
 
@@ -8,9 +7,30 @@ pub trait Reporter {
     fn report<'a, M: Into<Cow<'a, str>>>(&self, key: M, report: &mut Report);
 }
 
-impl Reporter for ExitStatus {
+impl<T, E> Reporter for Result<T, E>
+where
+    T: Reporter,
+{
     fn report<'a, M: Into<Cow<'a, str>>>(&self, key: M, report: &mut Report) {
-        report.insert(key.into().into_owned(), self.success());
+        match self {
+            Err(_) => {
+                report.insert(key.into().into_owned(), false);
+            }
+            Ok(item) => {
+                item.report(key, report);
+            }
+        }
+    }
+}
+
+impl<T> Reporter for Option<T>
+where
+    T: Reporter,
+{
+    fn report<'a, M: Into<Cow<'a, str>>>(&self, key: M, report: &mut Report) {
+        if let Some(item) = self {
+            item.report(key, report);
+        }
     }
 }
 
@@ -19,3 +39,9 @@ impl Reporter for bool {
         report.insert(key.into().into_owned(), *self);
     }
 }
+
+impl Reporter for () {
+    fn report<'a, M: Into<Cow<'a, str>>>(&self, key: M, report: &mut Report) {
+        report.insert(key.into().into_owned(), true);
+    }
+}