configparser: sniff identity when loading config

Summary:
Now configparser::hg::load will sniff the identity from either the repo_path, if provided, or else the environment.

This only means that it will load the repo config from .sl instead of .hg as appropriate.

I also tweaked eagerepo to sniff the identity instead of assuming ".hg" to aid in testing.

Reviewed By: DurhamG

Differential Revision: D39040645

fbshipit-source-id: fce46d1537028634b644bfd3dc4de684b9f88410

Author: Muir Manders

eden/scm/lib/configparser/Cargo.toml

@@ -21,6 +21,7 @@ hgtime = { version = "0.1.0", path = "../hgtime", optional = true }
 hostcaps = { version = "0.1.0", git = "https://github.com/facebookexperimental/rust-shed.git", branch = "main" }
 hostname = "0.3"
 http-client = { version = "0.1.0", path = "../http-client", optional = true }
+identity = { version = "0.1.0", path = "../identity" }
 indexmap = { version = "1.8.0", features = ["rayon", "serde-1"] }
 minibytes = { version = "0.1.0", path = "../minibytes" }
 pest-hgrc = { version = "0.1.0", path = "pest-hgrc" }

eden/scm/lib/configparser/src/hg.rs

@@ -262,7 +262,12 @@ impl ConfigSetHgExt for ConfigSet {
     ) -> Result<SupersetVerification, Errors> {
         tracing::info!(?repo_path, "loading config");
 
-        let repo_path = repo_path.map(|p| p.join(".hg"));
+        let ident = repo_path
+            .map(|p| identity::must_sniff_dir(p).map_err(|e| Errors(vec![Error::Other(e)])))
+            .transpose()?;
+        let ident = ident.unwrap_or_else(identity::sniff_env);
+
+        let repo_path = repo_path.map(|p| p.join(ident.dot_dir()));
 
         let mut errors = vec![];
 

eden/scm/lib/eagerepo/Cargo.toml

@@ -13,6 +13,7 @@ edenapi_trait = { version = "0.1.0", path = "../edenapi/trait" }
 fail = { version = "0.4", features = ["failpoints"] }
 futures = { version = "0.3.13", features = ["async-await", "compat"] }
 http = "0.2"
+identity = { version = "0.1.0", path = "../identity" }
 metalog = { version = "0.1.0", path = "../metalog" }
 minibytes = { version = "0.1.0", path = "../minibytes" }
 nonblocking = { version = "0.1.0", path = "../nonblocking" }

eden/scm/lib/eagerepo/src/eager_repo.rs

@@ -128,8 +128,9 @@ impl EagerRepoStore {
 impl EagerRepo {
     /// Open an [`EagerRepo`] at the given directory. Create an empty repo on demand.
     pub fn open(dir: &Path) -> Result<Self> {
+        let ident = identity::sniff_dir(dir)?.unwrap_or_else(identity::sniff_env);
         // Attempt to match directory layout of a real client repo.
-        let hg_dir = dir.join(".hg");
+        let hg_dir = dir.join(ident.dot_dir());
         let store_dir = hg_dir.join("store");
         let dag = Dag::open(store_dir.join("segments/v1"))?;
         let store = EagerRepoStore::open(&store_dir.join("hgcommits/v1"))?;

eden/scm/lib/identity/src/lib.rs

@@ -11,6 +11,8 @@ use std::io;
 use std::path::Path;
 use std::path::PathBuf;
 
+use anyhow::Context;
+use anyhow::Error;
 use anyhow::Result;
 use once_cell::sync::Lazy;
 use parking_lot::RwLock;
@@ -118,7 +120,9 @@ pub fn sniff_dir(path: &Path) -> Result<Option<Identity>> {
                 // don't infer the wrong identity. Ideally this would
                 // be an allowlist of errors, but unstable errors like
                 // NotADirectory are unmatchable for now.
-                return Err(err.into());
+                return Err::<_, Error>(err.into()).with_context(|| {
+                    format!("error sniffing {} for identity", test_path.display())
+                });
             }
             _ => {}
         };
@@ -127,6 +131,11 @@ pub fn sniff_dir(path: &Path) -> Result<Option<Identity>> {
     Ok(None)
 }
 
+/// Like sniff_dir, but returns an error instead of None.
+pub fn must_sniff_dir(path: &Path) -> Result<Identity> {
+    sniff_dir(path)?.with_context(|| format!("repo {} missing dot dir", path.display()))
+}
+
 /// Recursively sniff path and its ancestors for the first directory
 ///  containing a ".hg" or ".sl" directory. The ancestor directory and
 ///  corresponding Identity are returned, if any. Only permission

eden/scm/tests/test-identity.t

@@ -7,42 +7,42 @@
   $ newrepo
   $ mv .hg .sl
 
-Command doesn't work, but we don't get "not inside a repository error":
-  $ LOG=identity=debug hg root
-  DEBUG identity: sniffing for repo root start=$TESTTMP/repo1
-  DEBUG identity: sniffed repo dir id=sl path=$TESTTMP/repo1
-  DEBUG identity: sniffed repo dir id=sl path=$TESTTMP/repo1
-  hg: parse errors: required config not found at $TESTTMP/repo1/.hg/hgrc.dynamic
-  
-  [255]
+"root" works in a .sl repo.
+  $ hg root
+  $TESTTMP/repo1
 
   $ cd ..
 
 
   $ mkdir sapling
   $ cd sapling
-Doesn't work yet, but we create a .sl directory.
-  $ HGIDENTITY=sl hg init 2>&1 | grep error
-  error.RustError: required config not found at $TESTTMP/sapling/.hg/hgrc.dynamic
+Init can create a ".sl" repo.
+  $ HGIDENTITY=sl hg init
   $ ls .hg
   $ ls .sl
   00changelog.i
+  hgrc.dynamic
   reponame
   requires
   store
 
   $ cd ..
 
-  $ newrepo clone_me
+  $ newremoterepo clone_me
+  $ setconfig paths.default=test:clone_me
   $ touch foo
-  $ hg commit -A -m foo -q
-  $ cd ..
-Doesn't work yet, but tries to create a .sl repo.
-  $ HGIDENTITY=sl LOG=identity=debug hg clone eager:clone_me cloned
-  DEBUG identity: sniffing for repo root start=$TESTTMP
-  Cloning reponame-default into $TESTTMP/cloned
-   INFO identity: sniffed identity from env identity="sl"
-  DEBUG identity: sniffed repo dir id=sl path=$TESTTMP/cloned
-  hg: parse errors: required config not found at $TESTTMP/cloned/.hg/hgrc.dynamic
-  
-  [255]
+  $ hg commit -Aq -m foo
+  $ hg push -r . --to master --create -q
+
+Clone can create a ".sl" repo.
+  $ HGIDENTITY=sl hg clone -Uq eager:clone_me cloned
+  $ ls cloned/.hg
+  $ ls cloned/.sl
+  00changelog.i
+  dirstate
+  hgrc
+  hgrc.dynamic
+  reponame
+  requires
+  store
+  treestate