error reporting

packages/mdbook_trpl/src/config/mod.rs

@@ -1,4 +1,4 @@
-//! Get any `preprocessor.trpl` config.
+//! Get any `preprocessor.trpl-*` config.
 
 use mdbook::preprocess::PreprocessorContext;
 
@@ -45,7 +45,7 @@ pub struct ParseErr;
 impl TryFrom<&str> for Mode {
     type Error = ParseErr;
 
-    fn try_from(value: &str) -> std::prelude::v1::Result<Self, Self::Error> {
+    fn try_from(value: &str) -> Result<Self, Self::Error> {
         match value {
             "default" => Ok(Mode::Default),
             "simple" => Ok(Mode::Simple),
@@ -57,7 +57,7 @@ impl TryFrom<&str> for Mode {
 #[derive(Debug, thiserror::Error)]
 pub enum Error {
     #[error(transparent)]
-    Mdbook(mdbook::errors::Error),
+    Mdbook(#[from] mdbook::errors::Error),
 
     #[error("No config for '{0}'")]
     NoConfig(String),

packages/mdbook_trpl/src/error.rs

@@ -0,0 +1,32 @@
+pub struct Report(Box<dyn std::error::Error>);
+
+#[derive(Debug, thiserror::Error)]
+#[error("{0}")]
+struct Simple(String);
+
+impl Report {
+    pub fn simple(s: impl Into<String>) -> Report {
+        Report(Box::new(Simple(s.into())))
+    }
+}
+
+impl<E> From<E> for Report
+where
+    E: std::error::Error + 'static,
+{
+    fn from(value: E) -> Self {
+        Report(Box::new(value))
+    }
+}
+
+impl std::fmt::Debug for Report {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        writeln!(f, "{:?}", self.0)?;
+        let mut current_err = self.0.as_ref();
+        while let Some(source_err) = current_err.source() {
+            writeln!(f, "Caused by: {:?}", source_err)?;
+            current_err = source_err;
+        }
+        Ok(())
+    }
+}