feat: let a configured project state its bead prefix

docs/configuration.md

@@ -27,6 +27,7 @@ path = "/home/you/arkham"
 name = "dunwich"
 path = "/srv/work/dunwich"
 environment_command = "nix develop -c"
+prefix = "dun"
 
 [[projects]]
 name = "kadath"
@@ -127,6 +128,15 @@ says why.
 It runs inside the project's environment, and its output is captured rather
 than passed on a command line, so the password never shows in `ps`.
 
+**`prefix`** is the prefix the project's tracker gives its beads, written as
+`bd init --prefix` takes it: `prefix = "dun"` for beads named `dun-7`. `bdi`
+learns a prefix from the beads a tracker answers with, so this only matters
+for a project it has not read. With it, a blocker
+carrying the prefix is drawn as this project's bead, which was not read, and a
+blocker carrying another prefix is never put down to this project. A project
+stating none may hold any blocker whose prefix no answer carries, so the line
+lists it among the projects not read.
+
 **`poll = false`** stops polling this project and relies on something
 [telling `bdi` when it changed](#telling-bdi-a-project-changed). Nothing then
 covers for a producer that dies, so the project's mark turns to `?` once

docs/design.md

@@ -951,12 +951,15 @@ that project's trees.
 tracker's beads carry its prefix, the id up to its first `-` as bd reads one,
 so the prefix says whose the bead would be. The line names the projects whose
 answers carry the prefix and hold no bead by that id, or the projects that
-each hold one. Where no answer carries the prefix, it names the configured
+each hold one. Where no answer carries the prefix, it falls to the configured
 projects that gave no answer, whether refused, unreachable or left out of the
 run, because nothing can learn the prefix of a tracker that did not answer.
-Where every configured project answered, the bead is in a project `bdi` is
-not configured to read. A parent no answer holds gets no such line, because
-it would have been drawn above the bead rather than beneath it. The tree's
+Only a project's config can state it. Where one of them states the prefix,
+the line says the bead is in that project, which was not read. Otherwise it
+names the ones that may hold it: those stating the prefix, or failing any,
+those stating none. Where no configured project may hold it, the bead is in a
+project `bdi` is not configured to read. A parent no answer holds gets no such
+line, because it would have been drawn above the bead rather than beneath it. The tree's
 note still counts every bead waiting on something missing, because a fold
 can hide the line.
 
@@ -2045,8 +2048,10 @@ refusing conflict as `refused`, and one it did not omits the field.
 `orphaned_dependencies` is every blocker the bead waits on that no tracker
 holds, `[]` where there is none, each an `id` and a `reason`: `not-held` with
 the `projects` whose beads carry its prefix, `held-by-several` with the
-`projects` that each hold a bead by it, `not-read` with the configured
-`projects` that gave no answer, or `unconfigured` with none. `agents`
+`projects` that each hold a bead by it, `held-by-unread` with the one
+configured `project` that gave no answer and whose config states its prefix,
+`not-read` with the configured `projects` that gave no answer and may hold it,
+or `unconfigured` with none. `agents`
 says which agent provider was asked and how that went, so a consumer knows
 which tier it is reading and which program answered for it: `state` is
 `answering`, `not-answering` where the provider is there and did not — which

src/app/collection.rs

@@ -274,11 +274,11 @@ impl Collection {
         now: DateTime<Utc>,
     ) -> Snapshot {
         let answered: Vec<(&str, &ProjectWork)> = self.that_answered(cfg).collect();
-        let not_read: Vec<&str> = cfg
+        let not_read: Vec<(&str, Option<&str>)> = cfg
             .projects
             .iter()
-            .map(|project| project.name.as_str())
-            .filter(|project| !answered.iter().any(|(answering, _)| answering == project))
+            .map(|project| (project.name.as_str(), project.prefix.as_deref()))
+            .filter(|(project, _)| !answered.iter().any(|(answering, _)| answering == project))
             .collect();
         let drawn = reaching_across(&answered, &not_read);
 
@@ -481,10 +481,11 @@ type Drawn<'a> = (&'a str, &'a str, Result<Cow<'a, Assembled>, &'a RootUnread>);
 /// bead waiting on work that answer does not hold is one each tree already
 /// names as an orphaned dependency. So only a tree naming one is assembled again, across
 /// every answer, and a run with none reads nothing twice. `not_read` is the
-/// configured projects that gave no answer, whichever bead they might hold.
+/// configured projects that gave no answer, each with the prefix its config
+/// states.
 fn reaching_across<'a>(
     answered: &[(&'a str, &'a ProjectWork)],
-    not_read: &[&'a str],
+    not_read: &[(&'a str, Option<&'a str>)],
 ) -> Vec<Drawn<'a>> {
     let waits_elsewhere = |read: &Result<Assembled, RootUnread>| {
         read.as_ref()

src/cli.rs

@@ -1144,6 +1144,7 @@ detached
             path: PathBuf::from("/srv/work/dunwich"),
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll,
             badges: Vec::new(),
             worktrees: Vec::new(),

src/collect/bd.rs

@@ -1025,6 +1025,7 @@ mod tests {
             path: project_dir(),
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),

src/collect/discovery.rs

@@ -75,6 +75,7 @@ pub fn from_the_current_directory(
             path: root,
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees,
@@ -342,6 +343,7 @@ detached
                 path: PathBuf::from("/srv/work/dunwich"),
                 environment_command: None,
                 credential_command: None,
+                prefix: None,
                 poll: true,
                 badges: Vec::new(),
                 worktrees: vec![PathBuf::from("/srv/work/dunwich")],
@@ -1172,6 +1174,7 @@ path = "/tmp/seat-b/wt/crates/dish"
                 path: PathBuf::from("/srv/loose"),
                 environment_command: None,
                 credential_command: None,
+                prefix: None,
                 poll: true,
                 badges: Vec::new(),
                 worktrees: Vec::new(),

src/collect/environment.rs

@@ -288,6 +288,7 @@ mod tests {
             path: project_dir(),
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),
@@ -528,6 +529,7 @@ mod tests {
             path: project_dir(),
             environment_command: None,
             credential_command: Some("op read the/password".to_string()),
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),
@@ -629,6 +631,7 @@ mod tests {
             path: project_dir(),
             environment_command: None,
             credential_command: Some("op read the/password".to_string()),
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),
@@ -688,6 +691,7 @@ mod tests {
             path: project_dir(),
             environment_command: None,
             credential_command: Some(command.to_string()),
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),

src/config.rs

@@ -114,6 +114,12 @@ pub struct Project {
     /// to `ps`, so it stays rather than folding into one.
     #[serde(default)]
     pub credential_command: Option<String>,
+    /// The prefix this project's tracker gives its beads, as `bd init
+    /// --prefix` takes it. It says which project holds a bead id before that
+    /// project's tracker has answered, where nothing can learn the prefix
+    /// from its beads.
+    #[serde(default)]
+    pub prefix: Option<String>,
     /// Whether this project asks for itself every interval, or leaves saying
     /// its work has moved to whatever reports for it on the inbound channel.
     ///
@@ -1079,6 +1085,7 @@ credential_command = "secret-tool lookup tracker arkham"
 name = "kadath"
 path = "/home/user/dev/kadath"
 credential_command = "cat /home/user/dev/kadath/.beads-password"
+prefix = "kad"
 
 [[projects.badges]]
 key    = "metadata.delivery_pr"
@@ -1165,6 +1172,7 @@ path = "/home/user/dev/cinder"
                     path: PathBuf::from("/home/user/arkham"),
                     environment_command: None,
                     credential_command: Some("secret-tool lookup tracker arkham".to_string()),
+                    prefix: None,
                     poll: true,
                     badges: Vec::new(),
                     worktrees: Vec::new(),
@@ -1176,6 +1184,7 @@ path = "/home/user/dev/cinder"
                     credential_command: Some(
                         "cat /home/user/dev/kadath/.beads-password".to_string()
                     ),
+                    prefix: Some("kad".to_string()),
                     poll: true,
                     badges: vec![Badge {
                         key: "metadata.delivery_pr".to_string(),
@@ -1458,6 +1467,7 @@ title = ["title", "badge.metadata.jira", "badges"]
             path: PathBuf::from("/home/user").join(name),
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll: true,
             badges,
             worktrees: Vec::new(),
@@ -1731,6 +1741,15 @@ path = "/home/user/dev/kadath"
         assert_eq!(cfg.projects[0].environment_command, None);
     }
 
+    /// A config written before a project could state its prefix still
+    /// parses, and says nothing about whose a bead is.
+    #[test]
+    fn a_project_saying_nothing_about_its_prefix_states_none() {
+        let cfg = Config::from_toml(ONE_PROJECT).expect("parses");
+
+        assert_eq!(cfg.projects[0].prefix, None);
+    }
+
     const ONE_ENTERED_WITH_DIRENV: &str = r#"
 [[projects]]
 name = "kadath"

src/model/join.rs

@@ -454,6 +454,7 @@ mod tests {
             path: path.into(),
             environment_command: None,
             credential_command: None,
+            prefix: None,
             poll: true,
             badges: Vec::new(),
             worktrees: Vec::new(),