cli: Clarify user facing patch message

Now logic for parsing and supporting user facing Patch messages is
shared for creation and editing, refactor and move supporting code to
terminal::patch.

This fixes a bug where the title may be incorrectly parsed, resulting in
it containing multiple lines.

radicle-cli/src/commands/patch/common.rs

@@ -11,18 +11,6 @@ use crate::terminal::args::Error;
 
 use super::Options;
 
-pub const PATCH_MSG: &str = r#"
-<!--
-Please enter a patch message for your changes. An empty
-message aborts the patch proposal.
-
-The first line is the patch title. The patch description
-follows, and must be separated with a blank line, just
-like a commit message. Markdown is supported in the title
-and description.
--->
-"#;
-
 /// Give the name of the branch or an appropriate error.
 #[inline]
 pub fn branch_name<'a>(branch: &'a git::raw::Branch) -> anyhow::Result<&'a str> {

radicle-cli/src/commands/patch/create.rs

@@ -12,28 +12,6 @@ use crate::terminal as term;
 use super::common::*;
 use super::Options;
 
-pub fn handle_patch_message(
-    message: term::patch::Message,
-    storage: &Repository,
-    head_branch: &git::raw::Branch,
-) -> anyhow::Result<(String, String)> {
-    let head_oid = branch_oid(head_branch)?;
-    let head_commit = storage.backend.find_commit(*head_oid)?;
-    let commit_message = head_commit
-        .message()
-        .ok_or(anyhow!("commit summary is not valid UTF-8; aborting"))?;
-    let message = message.get(&format!("{commit_message}{PATCH_MSG}"))?;
-    let message = message.replace(PATCH_MSG.trim(), ""); // Delete help message.
-    let (title, description) = message.split_once("\n\n").unwrap_or((&message, ""));
-    let (title, description) = (title.trim(), description.trim());
-
-    if title.is_empty() {
-        anyhow::bail!("a patch title must be provided");
-    }
-
-    Ok((title.to_string(), description.to_owned()))
-}
-
 fn show_patch_commit_info(
     storage: &Repository,
     node_id: &NodeId,
@@ -102,8 +80,13 @@ pub fn run(
 
     // TODO: List matching working copy refs for all targets.
 
-    let (title, description) = handle_patch_message(message, storage, &head_branch)?;
     let head_oid = branch_oid(&head_branch)?;
+    let head_commit = storage.backend.find_commit(*head_oid)?;
+    let head_commit_msg = head_commit
+        .message()
+        .ok_or(anyhow!("commit summary is not valid UTF-8; aborting"))?;
+    let (title, description) = term::patch::get_message(message, head_commit_msg)?;
+
     let base_oid = storage.backend.merge_base(*target_oid, *head_oid)?;
     let signer = term::signer(profile)?;
     let patch = if draft {

radicle-cli/src/commands/patch/edit.rs

@@ -1,10 +1,11 @@
-use super::common::*;
 use super::*;
 
 use radicle::cob::patch;
 use radicle::prelude::*;
 use radicle::storage::git::Repository;
 
+use crate::terminal as term;
+
 pub fn run(
     repository: &Repository,
     profile: &Profile,
@@ -17,26 +18,14 @@ pub fn run(
         anyhow::bail!("Patch `{patch_id}` not found");
     };
 
-    let title = patch.title();
-    let description = patch.description();
-    let message = message.get(&format!("{title}\n\n{description}\n\n{PATCH_MSG}"))?;
-    let message = message.replace(PATCH_MSG.trim(), ""); // Delete help message.
-    let (title, description) = message.split_once("\n\n").unwrap_or((&message, ""));
-    let (title, description) = (title.trim(), description.trim());
+    let default_msg = term::patch::message(patch.title(), patch.description());
+    let (title, description) = term::patch::get_message(message, &default_msg)?;
 
-    if title.is_empty() {
-        anyhow::bail!("a patch title must be provided");
-    } else if title == patch.title() && description == patch.description() {
+    if title == patch.title() && description == patch.description() {
         // Nothing to do
         return Ok(());
     }
-
-    patch.edit(
-        title.to_string(),
-        description.to_string(),
-        patch.target(),
-        &signer,
-    )?;
+    patch.edit(title, description, patch.target(), &signer)?;
 
     Ok(())
 }

radicle-cli/src/terminal/patch.rs

@@ -43,6 +43,47 @@ impl Default for Message {
     }
 }
 
+pub const PATCH_MSG: &str = r#"
+<!--
+Please enter a patch message for your changes. An empty
+message aborts the patch proposal.
+
+The first line is the patch title. The patch description
+follows, and must be separated with a blank line, just
+like a commit message. Markdown is supported in the title
+and description.
+-->
+"#;
+
+/// Combine the title and description fields to display to the user.
+#[inline]
+pub fn message(title: &str, description: &str) -> String {
+    format!("{title}\n\n{description}").trim().to_string()
+}
+
+/// Get the Patch title and description from the command line arguments, or request it from the
+/// user.
+///
+/// The user can bail out if an empty title is entered.
+pub fn get_message(
+    message: term::patch::Message,
+    default_msg: &str,
+) -> anyhow::Result<(String, String)> {
+    let display_msg = default_msg.trim_end();
+
+    let message = message.get(&format!("{display_msg}\n{PATCH_MSG}"))?;
+    let message = message.replace(PATCH_MSG.trim(), ""); // Delete help message.
+
+    let (title, description) = message.split_once('\n').unwrap_or((&message, ""));
+    let (title, description) = (title.trim().to_string(), description.trim().to_string());
+
+    if title.is_empty() {
+        anyhow::bail!("a patch title must be provided");
+    }
+
+    Ok((title, description))
+}
+
 /// List the given commits in a table.
 pub fn list_commits(commits: &[git::raw::Commit]) -> anyhow::Result<()> {
     let mut table = term::Table::default();
@@ -80,3 +121,38 @@ pub fn print_commits_ahead_behind(
     );
     Ok(())
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_get_message() {
+        let res = get_message(
+            Message::Text("title\n\ndescription".to_string()),
+            "default text",
+        )
+        .unwrap();
+        assert_eq!(("title".to_string(), "description".to_string()), res);
+
+        let res = get_message(
+            Message::Text("title\ndescription\nsecond description".to_string()),
+            "default text",
+        )
+        .unwrap();
+        assert_eq!(
+            (
+                "title".to_string(),
+                "description\nsecond description".to_string()
+            ),
+            res
+        );
+
+        let res = get_message(
+            Message::Text(" title \ndescription  \n \n ".to_string()),
+            "default text",
+        )
+        .unwrap();
+        assert_eq!(("title".to_string(), "description".to_string()), res);
+    }
+}