message: Added debug coveralls report file save.
diff: @@ -5,6 +5,8 @@ use coveralls_api::*;
  use log::{info, warn};
  use std::collections::HashMap;
  use std::path::Path;
  +use std::fs;
  +
  fn get_git_info(manifest_path: &Path) -> Result<GitInfo, String> {
  let dir_path = manifest_path
  @@ -52,6 +54,7 @@ fn get_git_info(manifest_path: &Path) -> Result<GitInfo, String> {
  })
  }
  +
  pub fn export(coverage_data: &TraceMap, config: &Config) -> Result<(), RunError> {
  if let Some(ref key) = config.coveralls {
  let id = match config.ci_tool {
  @@ -110,7 +113,14 @@ pub fn export(coverage_data: &TraceMap, config: &Config) -> Result<(), RunError>
  report.send_to_coveralls()
  }
  };
  -
  + if config.debug {
  + if let Ok(text) = serde_json::to_string(&report) {
  + info!("Attempting to write coveralls report to coveralls.json");
  + let _ = fs::write("coveralls.json", text);
  + } else {
  + warn!("Failed to serialise coverage report");
  + }
  + }
  match res {
  Ok(_) => Ok(()),
  Err(e) => Err(RunError::CovReport(format!("Coveralls send failed. {}", e))),
  