bug: Fix silent failures in file I/O operations #211

New issue

Closed

opened 2026-01-09 04:42:53 +00:00 by navicore · 1 comment

navicore commented

2026-01-09 04:42:53 +00:00

(Migrated from github.com)

Problem

File I/O operations silently swallow errors using .unwrap_or_default(), hiding failures from users and making debugging difficult.

Example from `crates/repl/src/app.rs` (lines 156-162):

let content = if !path.exists() {
    // ... create new file
} else {
    fs::read_to_string(&path).unwrap_or_default()  // SILENT FAILURE!
};

If the file exists but cannot be read (permissions, corruption, etc.), this returns an empty string instead of reporting the error.

Impact

Users lose data without knowing why
Debugging becomes difficult ("why is my session empty?")
Corruption or permission issues go unnoticed
Violates principle of least surprise

Affected Locations

crates/repl/src/app.rs:161 - Session file reading
Other potential locations with .unwrap_or_default() on I/O operations

Proposed Solution

For recoverable errors (display warning, continue):

let content = match fs::read_to_string(&path) {
    Ok(c) => c,
    Err(e) => {
        eprintln!("Warning: Could not read session file: {}", e);
        String::new()  // Start fresh, but user knows why
    }
};

For critical errors (propagate):

fn load_session(&mut self) -> Result<(), SessionError> {
    let content = fs::read_to_string(&self.session_file)
        .map_err(|e| SessionError::ReadFailed(e))?;
    // ...
}

Acceptance Criteria

Audit all .unwrap_or_default() calls on I/O operations
Replace with explicit error handling (warning or propagation)
Users see meaningful messages when files cannot be read
Add tests for I/O error conditions

Labels

bug, ux, medium-priority

## Problem File I/O operations silently swallow errors using `.unwrap_or_default()`, hiding failures from users and making debugging difficult. ### Example from `crates/repl/src/app.rs` (lines 156-162): ```rust let content = if !path.exists() { // ... create new file } else { fs::read_to_string(&path).unwrap_or_default() // SILENT FAILURE! }; ``` If the file exists but cannot be read (permissions, corruption, etc.), this returns an empty string instead of reporting the error. ## Impact - Users lose data without knowing why - Debugging becomes difficult ("why is my session empty?") - Corruption or permission issues go unnoticed - Violates principle of least surprise ## Affected Locations 1. `crates/repl/src/app.rs:161` - Session file reading 2. Other potential locations with `.unwrap_or_default()` on I/O operations ## Proposed Solution ### For recoverable errors (display warning, continue): ```rust let content = match fs::read_to_string(&path) { Ok(c) => c, Err(e) => { eprintln!("Warning: Could not read session file: {}", e); String::new() // Start fresh, but user knows why } }; ``` ### For critical errors (propagate): ```rust fn load_session(&mut self) -> Result<(), SessionError> { let content = fs::read_to_string(&self.session_file) .map_err(|e| SessionError::ReadFailed(e))?; // ... } ``` ## Acceptance Criteria - [ ] Audit all `.unwrap_or_default()` calls on I/O operations - [ ] Replace with explicit error handling (warning or propagation) - [ ] Users see meaningful messages when files cannot be read - [ ] Add tests for I/O error conditions ## Labels bug, ux, medium-priority

navicore commented

2026-01-10 17:53:13 +00:00

(Migrated from github.com)

https://github.com/navicore/patch-seq/pull/224