drop legacy .harmont support entirely (clean break)

Remove the ~/.harmont config/credential forward-migration and the legacy
.harmont/ project-dir detection hint — no point keeping the old directory
alive. Keeps the HARMONT_* env-var plumbing and the api_url->env move.

- hm-util: drop legacy_hm_config_dir()
- hm-config: drop creds legacy_path fallback; drop the legacy config layer
  (collapse load_layered back into load_from_paths, env layering retained)
- hm-dsl-engine: detect bails plainly when .hm/ is absent (no .harmont hint)

Author: markovejnovic

crates/hm-config/src/creds.rs

@@ -20,30 +20,14 @@ fn path() -> Result<PathBuf> {
     Ok(dir.join("credentials.toml"))
 }
 
-/// Pre-rename (v0.0.5) credential file at `~/.harmont/credentials.toml`.
-///
-/// The on-disk format is unchanged across the rename, so we read it through
-/// as a fallback when the new location is empty. Writes always target the new
-/// [`path`], so the first `hm cloud login`/`set` after upgrade migrates the
-/// store forward.
-fn legacy_path() -> Option<PathBuf> {
-    hm_util::dirs::legacy_hm_config_dir().map(|d| d.join("credentials.toml"))
-}
-
 fn load() -> CredentialFile {
-    if let Ok(p) = path()
-        && let Ok(contents) = std::fs::read_to_string(&p)
-    {
-        return toml::from_str(&contents).unwrap_or_default();
-    }
-    // New location absent/unreadable: fall back to the legacy store so tokens
-    // and the active org written by the pre-rename CLI survive an upgrade.
-    if let Some(legacy) = legacy_path()
-        && let Ok(contents) = std::fs::read_to_string(&legacy)
-    {
-        return toml::from_str(&contents).unwrap_or_default();
-    }
-    CredentialFile::default()
+    let Ok(p) = path() else {
+        return CredentialFile::default();
+    };
+    let Ok(contents) = std::fs::read_to_string(&p) else {
+        return CredentialFile::default();
+    };
+    toml::from_str(&contents).unwrap_or_default()
 }
 
 fn save(file: &CredentialFile) -> Result<()> {

crates/hm-config/src/lib.rs

@@ -96,33 +96,15 @@ impl Config {
     /// figment extraction fails (malformed TOML, type mismatches).
     pub fn load(project_root: Option<&Path>) -> Result<Self> {
         let user_path = Self::user_config_path()?;
-        let legacy_user_path = hm_util::dirs::legacy_hm_config_dir().map(|d| d.join("config.toml"));
         let project_path = project_root.map(Self::project_config_path);
-        Self::load_layered(
-            legacy_user_path.as_deref(),
-            Some(&user_path),
-            project_path.as_deref(),
-        )
-        .context("loading configuration")
+        Self::load_from_paths(Some(&user_path), project_path.as_deref())
+            .context("loading configuration")
     }
 
     /// Testable core: build a `Config` from explicit file paths.
     ///
-    /// # Errors
-    ///
-    /// Returns an error if figment extraction fails (malformed TOML, type mismatches).
-    pub fn load_from_paths(user_path: Option<&Path>, project_path: Option<&Path>) -> Result<Self> {
-        Self::load_layered(None, user_path, project_path)
-    }
-
-    /// Build a `Config` from explicit file paths with an optional legacy
-    /// (`~/.harmont/`) user layer at the bottom.
-    ///
-    /// Layering, lowest to highest precedence: defaults -> legacy user file
-    /// -> user file -> project file -> env. The legacy layer means a custom
-    /// `[cloud] api_url`/`org` written by the pre-rename CLI survives an
-    /// upgrade even when the user never re-runs `hm cloud login`; an explicit
-    /// value in the new `~/.config/hm/config.toml` always wins over it.
+    /// Layering, lowest to highest precedence: defaults -> user file ->
+    /// project file -> env.
     ///
     /// Env precedence (highest): both the `HM_`-prefixed split form
     /// (`HM_CLOUD__ORG`, `HM_CLOUD__API_URL`) and the documented
@@ -132,16 +114,9 @@ impl Config {
     /// # Errors
     ///
     /// Returns an error if figment extraction fails (malformed TOML, type mismatches).
-    pub fn load_layered(
-        legacy_user_path: Option<&Path>,
-        user_path: Option<&Path>,
-        project_path: Option<&Path>,
-    ) -> Result<Self> {
+    pub fn load_from_paths(user_path: Option<&Path>, project_path: Option<&Path>) -> Result<Self> {
         let mut figment = Figment::new().merge(Serialized::defaults(Self::default()));
 
-        if let Some(p) = legacy_user_path {
-            figment = figment.merge(Toml::file(p));
-        }
         if let Some(p) = user_path {
             figment = figment.merge(Toml::file(p));
         }
@@ -353,50 +328,6 @@ org = "project-org"
         assert_eq!(loaded.preferences.format, "human");
     }
 
-    #[test]
-    fn legacy_user_file_carried_forward_when_new_absent() {
-        let _g = env_guard();
-        // Pre-rename ~/.harmont/config.toml exists; new ~/.config/hm absent.
-        let legacy_toml = r#"
-[cloud]
-org = "legacy-org"
-api_url = "https://legacy.api"
-"#;
-        let mut legacy_file = tempfile::NamedTempFile::new().unwrap();
-        legacy_file.write_all(legacy_toml.as_bytes()).unwrap();
-
-        let absent_user = Path::new("/tmp/harmont-test-absent-user-cfg/config.toml");
-
-        let cfg = Config::load_layered(Some(legacy_file.path()), Some(absent_user), None).unwrap();
-        assert_eq!(cfg.cloud.org.as_deref(), Some("legacy-org"));
-        assert_eq!(cfg.cloud.api_url, "https://legacy.api");
-    }
-
-    #[test]
-    fn new_user_file_wins_over_legacy() {
-        let _g = env_guard();
-        let legacy_toml = r#"
-[cloud]
-org = "legacy-org"
-api_url = "https://legacy.api"
-"#;
-        let new_toml = r#"
-[cloud]
-org = "new-org"
-"#;
-        let mut legacy_file = tempfile::NamedTempFile::new().unwrap();
-        legacy_file.write_all(legacy_toml.as_bytes()).unwrap();
-        let mut new_file = tempfile::NamedTempFile::new().unwrap();
-        new_file.write_all(new_toml.as_bytes()).unwrap();
-
-        let cfg =
-            Config::load_layered(Some(legacy_file.path()), Some(new_file.path()), None).unwrap();
-        // Explicit value in the new file overrides the legacy one...
-        assert_eq!(cfg.cloud.org.as_deref(), Some("new-org"));
-        // ...while keys absent from the new file still fall through to legacy.
-        assert_eq!(cfg.cloud.api_url, "https://legacy.api");
-    }
-
     #[test]
     #[allow(clippy::result_large_err)] // figment::Error is the Jail closure's error type.
     fn harmont_env_overrides_cloud_keys() {

crates/hm-dsl-engine/src/detect.rs

@@ -15,7 +15,7 @@ use crate::DslLanguage;
 pub fn detect_language(repo_root: &Path) -> anyhow::Result<DslLanguage> {
     let harmont_dir = repo_root.join(".hm");
     if !harmont_dir.is_dir() {
-        missing_hm_dir(repo_root)?;
+        bail!("no .hm/ directory found in {}", repo_root.display());
     }
     match scan_extensions(repo_root)? {
         // When both languages are present, prefer TypeScript.
@@ -40,7 +40,7 @@ pub fn detect_language(repo_root: &Path) -> anyhow::Result<DslLanguage> {
 pub fn detect_language_python_first(repo_root: &Path) -> anyhow::Result<DslLanguage> {
     let harmont_dir = repo_root.join(".hm");
     if !harmont_dir.is_dir() {
-        missing_hm_dir(repo_root)?;
+        bail!("no .hm/ directory found in {}", repo_root.display());
     }
     match scan_extensions(repo_root)? {
         (true, _) => Ok(DslLanguage::Python),
@@ -49,21 +49,6 @@ pub fn detect_language_python_first(repo_root: &Path) -> anyhow::Result<DslLangu
     }
 }
 
-/// Bail with a doctrine-shaped error when `.hm/` is absent.
-///
-/// If the repo still carries a pre-rename `.harmont/` pipeline directory, the
-/// message points precisely at the rename and the one-line fix instead of the
-/// bare "no .hm/ directory found", which left upgrading users stranded.
-fn missing_hm_dir(repo_root: &Path) -> anyhow::Result<()> {
-    if repo_root.join(".harmont").is_dir() {
-        bail!(
-            "found a legacy .harmont/ pipeline directory in {} — it was renamed to .hm/ in this release\n  \u{2192} rename it: mv .harmont .hm",
-            repo_root.display()
-        );
-    }
-    bail!("no .hm/ directory found in {}", repo_root.display());
-}
-
 /// True when `.hm/` exists and holds at least one `.py` or `.ts` file.
 ///
 /// The backend fans pipeline discovery out across every repo in an
@@ -148,23 +133,6 @@ mod tests {
         assert!(msg.contains("no .hm/ directory"), "unexpected error: {msg}");
     }
 
-    #[test]
-    fn legacy_harmont_dir_emits_migration_hint() {
-        let tmp = TempDir::new().unwrap();
-        // Pre-rename layout: `.harmont/` present, `.hm/` absent.
-        fs::create_dir(tmp.path().join(".harmont")).unwrap();
-        let err = detect_language(tmp.path()).unwrap_err();
-        let msg = err.to_string();
-        assert!(msg.contains("legacy .harmont/"), "unexpected error: {msg}");
-        assert!(msg.contains("mv .harmont .hm"), "unexpected error: {msg}");
-        // The same hint flows through the python-first path.
-        let err2 = detect_language_python_first(tmp.path()).unwrap_err();
-        assert!(
-            err2.to_string().contains("mv .harmont .hm"),
-            "unexpected error: {err2}"
-        );
-    }
-
     #[test]
     fn empty_harmont_dir_is_error() {
         let tmp = TempDir::new().unwrap();

crates/hm-util/src/dirs.rs

@@ -17,16 +17,6 @@ pub fn hm_config_dir() -> Option<PathBuf> {
     platform::config_dir().map(|c| c.join("hm"))
 }
 
-/// `~/.harmont/` — the pre-rename (v0.0.5) user config root.
-///
-/// The config/credential format is unchanged across the rename, so callers
-/// use this as a best-effort fallback/migration source when the new
-/// `~/.config/hm/` location is empty. Returns `None` when the home directory
-/// cannot be determined.
-pub fn legacy_hm_config_dir() -> Option<PathBuf> {
-    platform::home_dir().map(|h| h.join(".harmont"))
-}
-
 /// `~/.cache/hm/` — local build cache root (regenerable).
 pub fn hm_cache_dir() -> Option<PathBuf> {
     platform::cache_dir().map(|c| c.join("hm"))
@@ -66,15 +56,6 @@ mod tests {
         );
     }
 
-    #[test]
-    fn legacy_hm_config_dir_is_dot_harmont() {
-        let p = legacy_hm_config_dir().unwrap();
-        assert!(
-            p.ends_with(".harmont"),
-            "expected path ending in '.harmont', got {p:?}"
-        );
-    }
-
     #[test]
     fn hm_cache_dir_under_cache() {
         let p = hm_cache_dir().unwrap();