feat(issue-4): make error reporting more user friendly (#11)

* feat(issue-444): make error reporting more user friendly

Intercept error `Result`s and log them properly, in red, printing only
the description.

This looks a lot better, to a final user, than the
json dump we used to have.

* add debug logging to the `BumpType` parser

src/bumping.rs

@@ -6,6 +6,7 @@ use std::str::FromStr;
 use git2::Commit;
 use semver::Version;
 use simple_error::SimpleError;
+use log::debug;
 
 /// Extension methods for `&str`, useful for handling conventional commits
 pub trait FirstLine<'a> {
@@ -80,7 +81,7 @@ impl<'a> TryFrom<Commit<'a>> for LogEntry<'a> {
 /// The different types of version bumps that one can do
 ///
 /// Can be created from a commit message.
-#[derive(Debug, Eq, Ord, PartialOrd, PartialEq)]
+#[derive(Copy, Clone, Debug, Eq, Ord, PartialOrd, PartialEq)]
 pub enum BumpType {
     None,
     Patch,
@@ -147,19 +148,21 @@ impl BumpType {
         let first_line = commit_msg.first_line();
         let conventional_prefix = first_line.prefix();
         let breaking = conventional_prefix.contains('!') || commit_msg.contains("\nBREAKING CHANGE");
-
-        if breaking {
-            BumpType::Major
-        } else if conventional_prefix.starts_with("fix") {
-            BumpType::Patch
-        } else if conventional_prefix.starts_with("feat") {
-            BumpType::Minor
-        } else {
-            if !OTHER_TYPES.contains(&conventional_prefix.as_str()) {
-                error_observer.on_error(commit_msg, first_line);
-            }
-            BumpType::None
-        }
+        let result =
+            if breaking {
+                BumpType::Major
+            } else if conventional_prefix.starts_with("fix") {
+                BumpType::Patch
+            } else if conventional_prefix.starts_with("feat") {
+                BumpType::Minor
+            } else {
+                if !OTHER_TYPES.contains(&conventional_prefix.as_str()) {
+                    error_observer.on_error(commit_msg, first_line);
+                }
+                BumpType::None
+            };
+        debug!(r#"parsed "{}" into {} bump"#, first_line, result);
+        result
     }
 }
 

src/main.rs

@@ -5,7 +5,7 @@ use fallible_iterator::FallibleIterator;
 use semver::Version;
 use simple_error::SimpleError;
 use structopt::StructOpt;
-use log::warn;
+use log::{warn, error};
 
 use crate::bumping::{Bump, BumpType};
 use crate::changelog::ChangeLog;
@@ -78,9 +78,25 @@ impl bumping::ObserveParseError for Vec<ParseError> {
     }
 }
 
-fn main() -> Result<(), Box<dyn Error>> {
+fn main() {
     let config: Config = Config::from_args();
-    stderrlog::new().module(module_path!()).verbosity(config.verbose + 2).init().unwrap();
+
+    if let Err(e) = what_bump(config) {
+        error!("{}", e);
+        print_error_cause(e.as_ref());
+        std::process::exit(1);
+    }
+}
+
+fn print_error_cause(error: &dyn Error) {
+    if let Some(error) = error.source() {
+        error!("caused by {}", error);
+        print_error_cause(error);
+    }
+}
+
+fn what_bump(config: Config) -> Result<(), Box<dyn Error>> {
+    stderrlog::new().module(module_path!()).verbosity(config.verbose + 2).init()?;
 
     match (config.bump, &config.from) {
         (Some(ref bump_type), Some(ref version)) => {