fix: less fragile dev brain sources revisions

src/app.rs

@@ -67,6 +67,7 @@ pub(crate) struct App {
     config: Config,
     preference_draft: PreferenceDraft,
     preference_error: Option<String>,
+    restore_dev_brain_confirmation: bool,
     selected_project: Option<i32>,
     selected_session: Option<i32>,
     /// Unsaved sessions, keyed by project. A draft only becomes a `sessions` row
@@ -361,6 +362,8 @@ pub(crate) enum Message {
     ChooseDevBrainVault,
     DevBrainVaultPicked(Option<PathBuf>),
     RestoreDevBrainDefaultGuides,
+    ConfirmRestoreDevBrainDefaultGuides,
+    CancelRestoreDevBrainDefaultGuides,
     PreferenceContextChanged(String),
     PreferenceMaxTokensChanged(String),
     PreferenceSystemPromptAction(text_editor::Action),
@@ -526,6 +529,7 @@ impl App {
                         config,
                         preference_draft,
                         preference_error: None,
+                        restore_dev_brain_confirmation: false,
                         selected_project: last_project,
                         selected_session: None,
                         drafts,
@@ -669,6 +673,7 @@ impl App {
             config,
             preference_draft,
             preference_error: None,
+            restore_dev_brain_confirmation: false,
             selected_project: None,
             selected_session: None,
             drafts: HashMap::new(),
@@ -951,6 +956,7 @@ impl App {
             Message::ClosePreferences => {
                 if let Some(id) = self.preferences_window {
                     self.preference_error = None;
+                    self.restore_dev_brain_confirmation = false;
                     return window::close(id);
                 }
             }
@@ -1033,6 +1039,7 @@ impl App {
                 if self.preferences_window == Some(id) {
                     self.preferences_window = None;
                     self.preference_error = None;
+                    self.restore_dev_brain_confirmation = false;
                 }
                 if self.help_window == Some(id) {
                     self.help_window = None;
@@ -1048,6 +1055,10 @@ impl App {
             Message::CancelQuit => self.quit_confirmation = false,
             Message::Escape(id) => {
                 if self.preferences_window == Some(id) {
+                    if self.restore_dev_brain_confirmation {
+                        self.restore_dev_brain_confirmation = false;
+                        return Task::none();
+                    }
                     return self.update(Message::ClosePreferences);
                 }
                 if id == self.main_window {
@@ -1239,11 +1250,19 @@ impl App {
                 }
             }
             Message::RestoreDevBrainDefaultGuides => {
+                self.preference_error = None;
+                self.restore_dev_brain_confirmation = true;
+            }
+            Message::ConfirmRestoreDevBrainDefaultGuides => {
+                self.restore_dev_brain_confirmation = false;
                 self.preference_error = crate::dev_brain::restore_default_guides(Path::new(
                     &self.preference_draft.dev_brain_vault_path,
                 ))
                 .err();
             }
+            Message::CancelRestoreDevBrainDefaultGuides => {
+                self.restore_dev_brain_confirmation = false;
+            }
             Message::PreferenceContextChanged(value) => {
                 self.preference_draft.context_tokens = value;
                 self.preference_error = None;

src/app/preferences.rs

@@ -358,6 +358,7 @@ impl App {
         }
         self.preference_draft = PreferenceDraft::from_saved(&self.config);
         self.preference_error = None;
+        self.restore_dev_brain_confirmation = false;
         let (id, open) = window::open(window::Settings {
             size: Size::new(920.0, 700.0),
             min_size: Some(Size::new(720.0, 480.0)),

src/app/view/preferences.rs

@@ -704,7 +704,7 @@ impl App {
         ]
         .spacing(8);
 
-        container(row![
+        let base: Element<'_, Message> = container(row![
             container(navigation)
                 .width(210)
                 .height(Length::Fill)
@@ -731,6 +731,39 @@ impl App {
         ])
         .width(Length::Fill)
         .height(Length::Fill)
+        .into();
+        if !self.restore_dev_brain_confirmation {
+            return base;
+        }
+        let confirmation = container(
+            column![
+                text("Recreate Dev Brain guidance?").size(22),
+                text("This replaces purpose.md and schema.md in the selected vault with this version's defaults. Topic pages, generated indexes, skills, and log.md are preserved.")
+                    .size(13),
+                row![
+                    Space::new().width(Length::Fill),
+                    action_button("Cancel")
+                        .on_press(Message::CancelRestoreDevBrainDefaultGuides),
+                    danger_button("Recreate files")
+                        .on_press(Message::ConfirmRestoreDevBrainDefaultGuides),
+                ]
+                .spacing(8),
+            ]
+            .spacing(14),
+        )
+        .padding(22)
+        .width(460)
+        .style(overview_style);
+        stack![
+            base,
+            opaque(
+                container(confirmation)
+                    .center_x(Length::Fill)
+                    .center_y(Length::Fill)
+                    .style(|_| container::Style::default()
+                        .background(Color::from_rgba8(0, 0, 0, 0.68)))
+            )
+        ]
         .into()
     }
 }

src/dev_brain.rs

@@ -74,14 +74,14 @@ sources:
   - project: Registered project name
     path: src/example.rs
     symbol: optional_symbol
-    revision: current-project-head-revision
+    revision: latest-commit-containing-this-file-content
-    # Use `git rev-parse HEAD`, or a unique lowercase hex prefix of at least 7 characters,
+    # For a clean tracked file, use `git log -1 --format=%H -- src/example.rs`,
-    # when this source file matches HEAD. Use hash when this file differs from HEAD,
+    # or a unique lowercase hex prefix of at least 7 characters. Use hash when
-    # is untracked, or the registered project is not Git.
+    # this file differs from HEAD, is untracked, or the registered project is not Git.
 ---
 ```
 
-`project` names a registered project, not this Dev Brain vault; `dev_brain_info` lists the exact registered names and folders. Each source `path` is relative to that registered project's folder; never resolve it inside the vault. Cite only files that support the page's claims, not every dirty file in the project. Each source has exactly one evidence version: `revision` or a lowercase SHA-256 `hash`. A revision is the current project HEAD's full object ID or a unique lowercase hexadecimal prefix of at least 7 characters, and is valid when that specific source file matches HEAD even if unrelated files are dirty. Use a hash when that specific file differs from HEAD, is untracked, or its registered project is not Git.
+`project` names a registered project, not this Dev Brain vault; `dev_brain_info` lists the exact registered names and folders. Each source `path` is relative to that registered project's folder; never resolve it inside the vault. Cite only files that support the page's claims, not every dirty file in the project. Each source has exactly one evidence version: `revision` or a lowercase SHA-256 `hash`. A revision is a commit whose version of that source file exactly matches the current clean file, preferably the latest commit returned by `git log -1 --format=%H -- path`; validation compares that file at the cited revision, not the repository's current HEAD. Use a hash when that specific file differs from HEAD, is untracked, or its registered project is not Git.
 
 ## Skills
 
@@ -601,7 +601,6 @@ impl DevBrain {
         )
         .load::<SourceKeyRow>(&mut self.connection)
         .map_err(|error| error.to_string())?;
-        let mut project_names = BTreeSet::new();
         for source in sources {
             let project = self
                 .projects
@@ -626,24 +625,11 @@ impl DevBrain {
                 path: format!("source:{}:{}", source.project, source.source_path),
                 modified_nanos,
                 size: metadata.len(),
-                hash: hash_file(&full)?,
+                hash: format!(
-            });
+                    "{}:{:?}",
-            project_names.insert(source.project);
+                    hash_file(&full)?,
-        }
+                    git_source_is_clean(&project.root, &full)
-        for name in project_names {
+                ),
-            let project = self
-                .projects
-                .iter()
-                .find(|project| project.name == name)
-                .unwrap();
-            let state = git_state(&project.root)
-                .map(|(revision, clean)| format!("{revision}:{clean}"))
-                .unwrap_or_default();
-            fingerprints.push(Fingerprint {
-                path: format!("git:{name}"),
-                modified_nanos: 0,
-                size: 0,
-                hash: state,
             });
         }
         fingerprints.sort_by(|left, right| left.path.cmp(&right.path));
@@ -1246,11 +1232,8 @@ fn validate_source(source: &SourceRecord, projects: &[RegisteredProject]) -> Res
         ));
     }
     if let Some(revision) = &source.revision {
-        return Ok(
+        return Ok(git_source_is_clean(&project.root, &resolved) == Some(true)
-            git_source_state(&project.root, &resolved).is_some_and(|(current, clean)| {
+            && git_revision_matches_source(&project.root, &relative, &resolved, revision));
-                clean && git_revision_matches(&project.root, revision, &current)
-            }),
-        );
     }
     let expected = source.hash.as_deref().unwrap();
     if expected.len() != 64
@@ -1264,64 +1247,46 @@ fn validate_source(source: &SourceRecord, projects: &[RegisteredProject]) -> Res
         ));
     }
     Ok(hash_file(&resolved)? == expected
-        && !git_source_state(&project.root, &resolved).is_some_and(|(_, clean)| clean))
+        && git_source_is_clean(&project.root, &resolved) != Some(true))
 }
 
-fn git_source_state(root: &Path, source: &Path) -> Option<(String, bool)> {
+fn git_source_is_clean(root: &Path, source: &Path) -> Option<bool> {
     let repository = git2::Repository::discover(root).ok()?;
-    let relative = source.strip_prefix(repository.workdir()?).ok()?;
+    let workdir = repository.workdir()?.canonicalize().ok()?;
-    let clean = repository.status_file(relative).ok()? == git2::Status::CURRENT;
+    let relative = source.strip_prefix(workdir).ok()?;
-    let revision = repository
+    Some(repository.status_file(relative).ok()? == git2::Status::CURRENT)
-        .head()
-        .ok()?
-        .peel_to_commit()
-        .ok()?
-        .id()
-        .to_string();
-    Some((revision, clean))
 }
 
-fn git_revision_matches(root: &Path, revision: &str, current: &str) -> bool {
+fn git_revision_matches_source(
-    if revision == current {
+    root: &Path,
-        return true;
+    relative: &Path,
-    }
+    source: &Path,
-    if revision.len() < 7
+    revision: &str,
-        || revision.len() >= current.len()
+) -> bool {
+    if !(7..=40).contains(&revision.len())
         || !revision
             .bytes()
             .all(|byte| byte.is_ascii_digit() || (b'a'..=b'f').contains(&byte))
     {
         return false;
     }
-    git2::Repository::discover(root)
+    let Some(matches) = (|| {
-        .ok()
-        .is_some_and(|repository| {
-            repository
-                .revparse_single(revision)
-                .ok()
-                .and_then(|object| object.peel_to_commit().ok())
-                .is_some_and(|commit| commit.id().to_string() == current)
-        })
-}
-
-fn git_state(root: &Path) -> Option<(String, bool)> {
         let repository = git2::Repository::discover(root).ok()?;
-    let revision = repository
+        let workdir = repository.workdir()?.canonicalize().ok()?;
-        .head()
+        let project = root.canonicalize().ok()?;
+        let path = project.strip_prefix(workdir).ok()?.join(relative);
+        let commit = repository
+            .revparse_single(revision)
             .ok()?
             .peel_to_commit()
-        .ok()?
+            .ok()?;
-        .id()
+        let entry = commit.tree().ok()?.get_path(&path).ok()?;
-        .to_string();
+        let blob = repository.find_blob(entry.id()).ok()?;
-    let mut options = git2::StatusOptions::new();
+        Some(fs::read(source).ok()?.as_slice() == blob.content())
-    options
+    })() else {
-        .include_untracked(true)
+        return false;
-        .recurse_untracked_dirs(true)
+    };
-        .include_ignored(false);
+    matches
-    Some((
-        revision,
-        repository.statuses(Some(&mut options)).ok()?.is_empty(),
-    ))
 }
 
 fn collect_managed_topics(
@@ -1954,21 +1919,23 @@ mod tests {
         index.write().unwrap();
         let tree = repository.find_tree(tree_id).unwrap();
         let signature = git2::Signature::now("DS4Server", "ds4@example.invalid").unwrap();
-        repository
+        let revision = repository
             .commit(Some("HEAD"), &signature, &signature, "Initial", &tree, &[])
-            .unwrap();
+            .unwrap()
+            .to_string();
         drop(tree);
         drop(repository);
-        let revision = git_state(&fixture.project).unwrap().0;
+        assert!(git_revision_matches_source(
-        assert!(git_revision_matches(
             &fixture.project,
-            &revision[..7],
+            Path::new("source.rs"),
-            &revision
+            &fixture.project.join("source.rs"),
+            &revision[..7]
         ));
-        assert!(!git_revision_matches(
+        assert!(!git_revision_matches_source(
             &fixture.project,
-            &revision[..6],
+            Path::new("source.rs"),
-            &revision
+            &fixture.project.join("source.rs"),
+            &revision[..6]
         ));
         let topic = fixture
             .topic("verified", &"0".repeat(64), "Revision-backed knowledge.")
@@ -1984,7 +1951,30 @@ mod tests {
                 .unwrap()
                 .contains("concepts/answer.md")
         );
+        let fingerprint = brain.current_fingerprint().unwrap();
         fs::write(fixture.project.join("unrelated.rs"), "dirty elsewhere\n").unwrap();
+        let repository = git2::Repository::open(&fixture.project).unwrap();
+        let mut index = repository.index().unwrap();
+        index.add_path(Path::new("unrelated.rs")).unwrap();
+        let tree_id = index.write_tree().unwrap();
+        index.write().unwrap();
+        let tree = repository.find_tree(tree_id).unwrap();
+        let parent = repository.head().unwrap().peel_to_commit().unwrap();
+        repository
+            .commit(
+                Some("HEAD"),
+                &signature,
+                &signature,
+                "Unrelated",
+                &tree,
+                &[&parent],
+            )
+            .unwrap();
+        drop(parent);
+        drop(tree);
+        drop(repository);
+        assert!(brain.current_fingerprint().unwrap() == fingerprint);
+        brain.validate().unwrap();
         assert!(
             brain
                 .search("Revision-backed knowledge", 10, true)
@@ -1998,6 +1988,33 @@ mod tests {
                 .unwrap()
                 .contains("status: stale")
         );
+        let repository = git2::Repository::open(&fixture.project).unwrap();
+        let mut index = repository.index().unwrap();
+        index.add_path(Path::new("source.rs")).unwrap();
+        let tree_id = index.write_tree().unwrap();
+        index.write().unwrap();
+        let tree = repository.find_tree(tree_id).unwrap();
+        let parent = repository.head().unwrap().peel_to_commit().unwrap();
+        repository
+            .commit(
+                Some("HEAD"),
+                &signature,
+                &signature,
+                "Source changed",
+                &tree,
+                &[&parent],
+            )
+            .unwrap();
+        drop(parent);
+        drop(tree);
+        drop(repository);
+        assert!(
+            brain
+                .validate()
+                .unwrap_err()
+                .contains("evidence has drifted")
+        );
+        fs::write(fixture.project.join("source.rs"), "dirty again\n").unwrap();
         let topic = fixture.topic(
             "verified",
             &source_hash(&fixture),