feat(check): add --strip flag when checking from stdin

Removes leading and trailing newlines and comments and trailing whitespace from the commit message read from stdin. It also colapses multiple empty lines into one.

Refs: #114

src/cli.rs

@@ -87,6 +87,10 @@ pub struct CheckCommand {
     /// Read a single commit message from stdin
     #[clap(long)]
     pub from_stdin: bool,
+    /// String comments and whitespace from commit message
+    /// This is similar to `git commit --cleanup=strip`
+    #[clap(long, requires("from_stdin"))]
+    pub strip: bool,
 }
 
 #[derive(Debug, Parser)]

src/cmd/check.rs

@@ -8,6 +8,7 @@ use crate::{
     cmd::Command,
     conventional::{self, Type},
     git::{filter_merge_commits, filter_revert_commits},
+    strip::Strip,
     Error,
 };
 
@@ -67,6 +68,9 @@ impl Command for CheckCommand {
             let mut stdin = stdin().lock();
             let mut commit_msg = String::new();
             stdin.read_to_string(&mut commit_msg)?;
+            if self.strip {
+                commit_msg = commit_msg.strip();
+            }
             parser.parse(&commit_msg)?;
             return Ok(());
         }

src/cmd/commit.rs

@@ -7,6 +7,7 @@ use serde::Serialize;
 use crate::{
     cli::CommitCommand,
     conventional::{config::Type, CommitParser, Config, ParseError},
+    strip::Strip,
     Command, Error,
 };
 
@@ -82,12 +83,7 @@ fn edit_message(msg: &str) -> Result<String, Error> {
         .require_save(false)
         .edit(msg)?
         .unwrap_or_default()
-        .lines()
-        .filter(|line| !line.starts_with('#'))
-        .collect::<Vec<&str>>()
-        .join("\n")
-        .trim()
-        .to_owned())
+        .strip())
 }
 
 #[derive(Serialize)]

src/main.rs

@@ -4,6 +4,7 @@ mod conventional;
 mod error;
 mod git;
 mod semver;
+mod strip;
 
 use std::process::exit;
 

src/strip.rs

@@ -0,0 +1,43 @@
+pub trait Strip {
+    fn strip(&self) -> String;
+}
+
+impl<T> Strip for T
+where
+    T: AsRef<str>,
+{
+    fn strip(&self) -> String {
+        fn strip(s: &str) -> String {
+            let iter = s
+                .lines()
+                .filter(|line| !line.starts_with('#'))
+                .map(|line| line.trim_end());
+            let mut lines: Vec<&str> = iter.collect();
+            lines.dedup_by(|a, b| a.trim().is_empty() && b.trim().is_empty());
+            lines.join("\n").trim().to_string()
+        }
+        strip(self.as_ref())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_name() {
+        let s = "#
+
+
+1
+2  
+3 
+
+
+4
+# 5
+
+";
+        assert_eq!("1\n2\n3\n\n4", s.strip());
+    }
+}