error: add MultiError for batch error aggregation

Signed-off-by: NotAShelf <raf@notashelf.dev>
Change-Id: I468289d7a5c3956fc410b6af1a8d070d6a6a6964

src/error.rs

@@ -2,6 +2,76 @@ use thiserror::Error;
 
 pub type Result<T> = std::result::Result<T, PakkerError>;
 
+/// Severity level for errors
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default)]
+pub enum ErrorSeverity {
+  /// Fatal error - operation cannot continue
+  #[default]
+  Error,
+  /// Warning - operation can continue but may have issues
+  Warning,
+  /// Info - informational message
+  Info,
+}
+
+/// Container for multiple errors that occurred during an operation
+#[derive(Debug)]
+pub struct MultiError {
+  errors: Vec<PakkerError>,
+}
+
+impl MultiError {
+  pub const fn new() -> Self {
+    Self { errors: Vec::new() }
+  }
+
+  pub fn push(&mut self, error: PakkerError) {
+    self.errors.push(error);
+  }
+
+  pub fn extend(&mut self, errors: impl IntoIterator<Item = PakkerError>) {
+    self.errors.extend(errors);
+  }
+
+  pub const fn is_empty(&self) -> bool {
+    self.errors.is_empty()
+  }
+
+  pub const fn len(&self) -> usize {
+    self.errors.len()
+  }
+
+  pub fn into_result<T>(self, success_value: T) -> Result<T> {
+    if self.is_empty() {
+      Ok(success_value)
+    } else {
+      Err(PakkerError::Multiple(self.errors))
+    }
+  }
+
+  pub fn errors(&self) -> &[PakkerError] {
+    &self.errors
+  }
+
+  pub fn into_errors(self) -> Vec<PakkerError> {
+    self.errors
+  }
+}
+
+impl Default for MultiError {
+  fn default() -> Self {
+    Self::new()
+  }
+}
+
+impl FromIterator<PakkerError> for MultiError {
+  fn from_iter<I: IntoIterator<Item = PakkerError>>(iter: I) -> Self {
+    Self {
+      errors: iter.into_iter().collect(),
+    }
+  }
+}
+
 #[derive(Error, Debug)]
 pub enum PakkerError {
   // Network errors
@@ -95,6 +165,21 @@ pub enum PakkerError {
 
   #[error("IPC error: {0}")]
   IpcError(String),
+
+  #[error("{}", format_multiple_errors(.0))]
+  Multiple(Vec<Self>),
+}
+
+fn format_multiple_errors(errors: &[PakkerError]) -> String {
+  if errors.len() == 1 {
+    return errors[0].to_string();
+  }
+
+  let mut msg = format!("{} errors occurred:\n", errors.len());
+  for (idx, error) in errors.iter().enumerate() {
+    msg.push_str(&format!("  {}. {}\n", idx + 1, error));
+  }
+  msg
 }
 
 impl From<git2::Error> for PakkerError {
@@ -108,3 +193,96 @@ impl From<crate::ipc::IpcError> for PakkerError {
     Self::IpcError(err.to_string())
   }
 }
+
+#[cfg(test)]
+mod tests {
+  use super::*;
+
+  #[test]
+  fn test_multi_error_empty() {
+    let multi = MultiError::new();
+    assert!(multi.is_empty());
+    assert_eq!(multi.len(), 0);
+  }
+
+  #[test]
+  fn test_multi_error_push() {
+    let mut multi = MultiError::new();
+    multi.push(PakkerError::ProjectNotFound("mod1".to_string()));
+    multi.push(PakkerError::ProjectNotFound("mod2".to_string()));
+
+    assert!(!multi.is_empty());
+    assert_eq!(multi.len(), 2);
+  }
+
+  #[test]
+  fn test_multi_error_into_result_empty() {
+    let multi = MultiError::new();
+    let result: Result<i32> = multi.into_result(42);
+    assert!(result.is_ok());
+    assert_eq!(result.unwrap(), 42);
+  }
+
+  #[test]
+  fn test_multi_error_into_result_with_errors() {
+    let mut multi = MultiError::new();
+    multi.push(PakkerError::ProjectNotFound("mod1".to_string()));
+
+    let result: Result<i32> = multi.into_result(42);
+    assert!(result.is_err());
+  }
+
+  #[test]
+  fn test_multi_error_from_iterator() {
+    let errors = vec![
+      PakkerError::ProjectNotFound("mod1".to_string()),
+      PakkerError::ProjectNotFound("mod2".to_string()),
+    ];
+    let multi: MultiError = errors.into_iter().collect();
+    assert_eq!(multi.len(), 2);
+  }
+
+  #[test]
+  fn test_multi_error_extend() {
+    let mut multi = MultiError::new();
+    multi.push(PakkerError::ProjectNotFound("mod1".to_string()));
+
+    let more_errors = vec![
+      PakkerError::ProjectNotFound("mod2".to_string()),
+      PakkerError::ProjectNotFound("mod3".to_string()),
+    ];
+    multi.extend(more_errors);
+
+    assert_eq!(multi.len(), 3);
+  }
+
+  #[test]
+  fn test_multiple_errors_formatting() {
+    let errors = vec![
+      PakkerError::ProjectNotFound("mod1".to_string()),
+      PakkerError::ProjectNotFound("mod2".to_string()),
+    ];
+    let error = PakkerError::Multiple(errors);
+    let msg = error.to_string();
+
+    assert!(msg.contains("2 errors occurred"));
+    assert!(msg.contains("mod1"));
+    assert!(msg.contains("mod2"));
+  }
+
+  #[test]
+  fn test_single_multiple_error_formatting() {
+    let errors = vec![PakkerError::ProjectNotFound("mod1".to_string())];
+    let error = PakkerError::Multiple(errors);
+    let msg = error.to_string();
+
+    // Single error should just display the error itself
+    assert!(msg.contains("mod1"));
+    assert!(!msg.contains("errors occurred"));
+  }
+
+  #[test]
+  fn test_error_severity_default() {
+    assert_eq!(ErrorSeverity::default(), ErrorSeverity::Error);
+  }
+}