feat: use anyhow for error handling of commands

Using anyhow it should be easier to find out what was wrong or improve the error message shown to the user.

Cargo.toml

@@ -18,6 +18,7 @@ include = [
 ]
 
 [dependencies]
+anyhow = { version = "1.0.62", features = ["backtrace"] }
 clap = { version = "3.2.6", features = ["derive"] }
 ctrlc = "3.2.2"
 dialoguer = "0.10.1"

src/cmd.rs

@@ -1,10 +1,10 @@
-use crate::{conventional::Config, Error};
+use crate::conventional::Config;
 
 mod changelog;
 mod check;
 mod commit;
 mod version;
 
 pub(crate) trait Command {
-    fn exec(&self, config: Config) -> Result<(), Error>;
+    fn exec(&self, config: Config) -> anyhow::Result<()>;
 }

src/cmd/changelog.rs

@@ -1,5 +1,6 @@
 use std::{cmp::Ordering, collections::HashMap, io::Write, path::PathBuf, str::FromStr};
 
+use anyhow::Context as _;
 use git2::Time;
 use time::Date;
 
@@ -260,7 +261,7 @@ impl<'a> ChangeLogTransformer<'a> {
 }
 
 impl ChangelogCommand {
-    pub(crate) fn write(&self, mut config: Config, stdout: impl Write) -> Result<(), Error> {
+    pub(crate) fn write(&self, mut config: Config, stdout: impl Write) -> anyhow::Result<()> {
         if self.no_links {
             config.link_references = false;
             config.link_compare = false;
@@ -293,7 +294,10 @@ impl ChangelogCommand {
 
         let transformer =
             ChangeLogTransformer::new(&config, self.include_hidden_sections, &helper, &self.paths)?;
-        match helper.find_last_version(rev)? {
+        match helper
+            .find_last_version(rev)
+            .with_context(|| format!("Could not find the last version for revision {rev}"))?
+        {
             Some(last_version) => {
                 let semver = SemVer::from_str(rev.trim_start_matches(&self.prefix));
                 let from_rev = if let Ok(ref semver) = &semver {
@@ -354,8 +358,9 @@ impl ChangelogCommand {
 }
 
 impl Command for ChangelogCommand {
-    fn exec(&self, config: Config) -> Result<(), Error> {
+    fn exec(&self, config: Config) -> anyhow::Result<()> {
         let stdout = std::io::stdout().lock();
-        self.write(config, stdout)
+        self.write(config, stdout)?;
+        Ok(())
     }
 }

src/cmd/check.rs

@@ -38,7 +38,7 @@ fn print_check(commit: &Commit<'_>, parser: &conventional::CommitParser, types:
 }
 
 impl Command for CheckCommand {
-    fn exec(&self, mut config: Config) -> Result<(), Error> {
+    fn exec(&self, mut config: Config) -> anyhow::Result<()> {
         if self.merges {
             config.merges = true;
         }
@@ -89,7 +89,7 @@ impl Command for CheckCommand {
             Ok(())
         } else {
             println!("\n{}/{} failed", fail, total);
-            Err(Error::Check)
+            Err(Error::Check)?
         }
     }
 }

src/cmd/commit.rs

@@ -196,7 +196,7 @@ impl Dialog {
 }
 
 impl Command for CommitCommand {
-    fn exec(&self, config: Config) -> Result<(), Error> {
+    fn exec(&self, config: Config) -> anyhow::Result<()> {
         let r#type = match (
             self.feat,
             self.fix,

src/cmd/version.rs

@@ -145,7 +145,7 @@ impl VersionCommand {
 }
 
 impl Command for VersionCommand {
-    fn exec(&self, config: Config) -> Result<(), Error> {
+    fn exec(&self, config: Config) -> anyhow::Result<()> {
         let (version, label) = self.get_version(config.scope_regex)?;
         if self.label {
             println!("{label}");

src/main.rs

@@ -28,10 +28,10 @@ fn main() -> Result<(), Error> {
     };
     match res {
         Err(e) => {
-            match e {
-                Error::Check => (),
+            match e.downcast_ref::<Error>() {
+                Some(Error::Check) => (),
                 _ => {
-                    eprintln!("{}", e);
+                    eprintln!("{:?}", e);
                 }
             }
             exit(1)