Add eyre for simple backtrace reporting

Add eyre for simple backtrace reporting. Since gfold relies on speed and
efficiency, and sports a relatively small codebase, eyre provides a
simple backtrace report when an error is encountered. Specifically, the
filename and line are the most important parts.
Unrelated, add a cargo doc command to the release Make target.
Adjust existing docs comments to match style.
Change some private definitions to be public.

5 files changed, 45 insertions, 19 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 2b1afd6..2daebc1 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -166,6 +166,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a357d28ed41a50f9c765dbfe56cbc04a64e53e5fc58ba79fbc34c10ef3df831f"
 
 [[package]]
+name = "eyre"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f4c5cb4dc433c59f09df4b4450f649cbfed61e8a3505abe32e4154066439157e"
+dependencies = [
+ "indenter",
+ "once_cell",
+]
+
+[[package]]
 name = "getrandom"
 version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -180,6 +190,7 @@ dependencies = [
 name = "gfold"
 version = "0.5.2"
 dependencies = [
+ "eyre",
  "git2",
  "prettytable-rs",
  "structopt",
@@ -230,6 +241,12 @@ dependencies = [
 ]
 
 [[package]]
+name = "indenter"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e0bd112d44d9d870a6819eb505d04dd92b5e4d94bb8c304924a0872ae7016fb5"
+
+[[package]]
 name = "itoa"
 version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -318,6 +335,12 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3728d817d99e5ac407411fa471ff9800a778d88a24685968b36824eaf4bee400"
 
 [[package]]
+name = "once_cell"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "260e51e7efe62b592207e9e13a68e43692a7a279171d6ba57abd208bf23645ad"
+
+[[package]]
 name = "openssl-probe"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
diff --git a/Cargo.toml b/Cargo.toml
index 7381ef0..dd67037 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -5,6 +5,7 @@ authors = ["Nick Gerace <nickagerace@gmail.com>"]
 edition = "2018"

 

 [dependencies]

+eyre = "0.6"

 structopt = "0.3"

 git2 = "0.13"

 prettytable-rs = "0.8"

diff --git a/Makefile b/Makefile
index 30b9645..a7f814e 100644
--- a/Makefile
+++ b/Makefile
@@ -49,12 +49,14 @@ fixme:
 		FIXME $(MAKEPATH)
 
 release:
-	@printf "Change version at the following locations...\n"
+	@printf "[1] Change version at the following locations...\n"
 	@printf "    Makefile: $(shell grep $(VERSION) $(MAKEPATH)/Makefile)\n"
 	@printf "    README.md: $(shell grep $(VERSION) $(MAKEPATH)/README.md)\n"
 	@printf "    CHANGELOG.md: $(shell grep $(VERSION) $(MAKEPATH)/CHANGELOG.md)\n"
 	@printf "    Cargo.toml: $(shell grep $(VERSION) $(MAKEPATH)/Cargo.toml)\n"
-	@printf "Uncomment the unreleased string in CHANGELOG.md...\n"
+	@printf "[2] Uncomment the unreleased string in CHANGELOG.md...\n"
 	@printf "    <!--The latest version contains all changes.-->\n"
-	@printf "Then, run the following command...\n"
+	@printf "[3] Run the following command to check documentation...\n"
+	@printf "    cargo doc --open\n"
+	@printf "[4] Then, run the following command...\n"
 	@printf "    time make build-release\n"
diff --git a/src/lib.rs b/src/lib.rs
index 674a75a..9f8d6da 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -9,18 +9,19 @@
 extern crate prettytable;
 
 use std::cmp::Ordering;
-use std::error::Error;
 use std::fs;
 use std::path::Path;
 use std::path::PathBuf;
 
+use eyre::Result;
+
 /// Creating a ```Results``` object requires using this ```struct``` as a pre-requisite.
-struct Config {
+pub struct Config {
     recursive: bool,
     skip_sort: bool,
 }
 
-/// This ```struct``` is a wrapper around the ```prettytable::Table``` object.
+/// This private ```struct``` is a wrapper around the ```prettytable::Table``` object.
 /// It exists to provide a label for the table.
 struct TableWrapper {
     path_string: String,
@@ -28,11 +29,11 @@ struct TableWrapper {
 }
 
 /// Contains all tables with results for each directory.
-struct Results(Vec<TableWrapper>);
+pub struct Results(Vec<TableWrapper>);
 
 impl Results {
     /// Create a new ```Results``` object with a given path and config.
-    fn new(path: &Path, config: &Config) -> Result<Results, Box<dyn Error>> {
+    pub fn new(path: &Path, config: &Config) -> Result<Results> {
         let mut results = Results(Vec::new());
         results.execute_in_directory(&config, path)?;
         if !&config.skip_sort {
@@ -42,8 +43,8 @@ impl Results {
     }
 
     /// Load results into the calling ```Results``` object via a given path and config.
-    /// This function may be called recursively.
-    fn execute_in_directory(&mut self, config: &Config, dir: &Path) -> Result<(), Box<dyn Error>> {
+    /// This private function may be called recursively.
+    fn execute_in_directory(&mut self, config: &Config, dir: &Path) -> Result<()> {
         // FIXME: find ways to add concurrent programming (tokio, async, etc.) to this section.
         let path_entries = fs::read_dir(dir)?;
         let mut repos = Vec::new();
@@ -72,7 +73,7 @@ impl Results {
 
     /// Sort the results alphabetically using ```sort_by_key```.
     /// This function will only perform the sort if there are at least two ```TableWrapper``` objects.
-    fn sort_results(&mut self) {
+    pub fn sort_results(&mut self) {
         if self.0.len() >= 2 {
             // FIXME: find a way to do this without "clone()".
             self.0.sort_by_key(|table| table.path_string.clone());
@@ -81,7 +82,7 @@ impl Results {
 
     /// Iterate through every table and print each to STDOUT.
     /// If there is only one table, this function avoids using a loop.
-    fn print_results(self) {
+    pub fn print_results(self) {
         match self.0.len().cmp(&1) {
             Ordering::Greater => {
                 for table_wrapper in self.0 {
@@ -100,6 +101,7 @@ impl Results {
 }
 
 /// Create a ```TableWrapper``` object from a given vector of paths (```Vec<PathBuf>```).
+/// This is a private helper function for ```execute_in_directory```.
 fn create_table_from_paths(repos: Vec<PathBuf>, path: &Path) -> Option<TableWrapper> {
     // For every path, we will create a mutable Table containing its results.
     let mut table = prettytable::Table::new();
@@ -181,7 +183,7 @@ fn create_table_from_paths(repos: Vec<PathBuf>, path: &Path) -> Option<TableWrap
 }
 
 /// This function is the primary driver for this file, ```lib.rs```.
-pub fn run(path: &Path, recursive: bool, skip_sort: bool) -> Result<(), Box<dyn Error>> {
+pub fn run(path: &Path, recursive: bool, skip_sort: bool) -> Result<()> {
     let config = Config {
         recursive,
         skip_sort,
diff --git a/src/main.rs b/src/main.rs
index 887bfc8..d13c1ff 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -7,8 +7,8 @@
 
 use std::env;
 use std::path::PathBuf;
-use std::process;
 
+use eyre::Result;
 use structopt::StructOpt;
 
 #[derive(StructOpt, Debug)]
@@ -30,7 +30,7 @@ struct Opt {
 
 /// This file, ```main.rs```, serves as the primary driver for the ```gfold``` library.
 /// It is intended to be used as a command-line interface.
-fn main() {
+fn main() -> Result<()> {
     let mut path = env::current_dir().expect("failed to get CWD");
 
     let opt = Opt::from_args();
@@ -39,8 +39,6 @@ fn main() {
     };
     path = path.canonicalize().expect("failed to canonicalize path");
 
-    if let Err(error) = gfold::run(&path, opt.recursive, opt.skip_sort) {
-        eprintln!("Encountered fatal error: {}", error);
-        process::exit(1);
-    };
+    gfold::run(&path, opt.recursive, opt.skip_sort)?;
+    Ok(())
 }