test-debugrevset: fix debugruntest compat

Summary:
The test requires the Rust implementation of `debugrevset`. However by setting
`workingcopy.use-rust` to False (default) the `clidispatch` would request
falling back to a Python implementation of `debugrevset`, which does not exist.

Fix it by setting `workingcopy.use-rust` to True. We should make sure
`run-tests.py` and `debugruntest` has a same view of default hgrc. But that
is a potentially breaking change and would be done separately.

Reviewed By: zzl0

Differential Revision: D42825820

fbshipit-source-id: db537c0226d205f9fc5d1a464a6ef4b4d8793185

eden/scm/edenscm/dispatch.py

@@ -1141,6 +1141,12 @@ def _dispatch(req):
         msg = _formatargs(fullargs)
         with perftrace.trace("Main Python Command"):
             repo = None
+            # Right now Rust `hgcommands` (undesirably) sets `func` to the
+            # command description, not a callable function.
+            if not callable(func):
+                raise error.ProgrammingError(
+                    f"'{cmd}' only has a Rust implementation but it wants to fallback to Python."
+                )
             if func.cmdtemplate:
                 templ = cmdtemplatestate(ui, cmdoptions)
                 args.insert(0, templ)

eden/scm/lib/clidispatch/src/dispatch.rs

@@ -406,6 +406,7 @@ impl Dispatcher {
 
         let res = || -> Result<u8> {
             add_global_flag_derived_configs(&mut self.optional_repo, parsed.clone().try_into()?);
+            tracing::debug!("command handled by a Rust function");
             match handler.func() {
                 CommandFunc::Repo(f) => f(parsed, io, self.repo_mut()?),
                 CommandFunc::OptionalRepo(f) => f(parsed, io, &mut self.optional_repo),
@@ -416,6 +417,9 @@ impl Dispatcher {
                 CommandFunc::WorkingCopy(f) => {
                     let repo = self.repo_mut()?;
                     if !repo.config().get_or_default("workingcopy", "use-rust")? {
+                        tracing::warn!(
+                            "command requires working copy but Rust working copy is disabled"
+                        );
                         // TODO(T131699257): Migrate all tests to use Rust
                         // workingcopy and removed fallback to Python.
                         return Err(errors::FallbackToPython("requested command that uses working copy but workingcopy.use-rust not set to True".to_owned()).into());

eden/scm/tests/test-debugrevset.t

@@ -1,6 +1,7 @@
-#chg-compatible
+#debugruntest-compatible
 
   $ configure modern
+  $ setconfig workingcopy.use-rust=True
 
 Setup repo:
   $ newclientrepo repo1

eden/scm/tests/test-eager-exchange.t

@@ -184,7 +184,7 @@ Read file content:
 Make a commit on tip, and amend. They do not trigger remote lookups:
 
   $ echo Z > Z
-  $ LOG=warn hg up -q tip
+  $ LOG=error hg up -q tip
   $ LOG=dag::protocol=debug,dag::cache=trace hg commit -Am Z Z
   TRACE dag::cache: cached missing ae226a63078b2a472fa38ec61318bb37e8c10bfb (definitely missing)
   DEBUG dag::cache: reusing cache (1 missing)