fix(lpb-config): status reported ahead as behind (swapped is-ancestor check)

cmd_status used 'merge-base --is-ancestor HEAD origin/<ref>': exit 0 means
local is BEHIND (or equal) but was reported 'up to date (or ahead)', while
local AHEAD fell into the 'behind remote' branch. Replace with
'rev-list --left-right --count' so status distinguishes up-to-date /
ahead / behind / diverged with exact counts.

Also use 'rev-parse --verify' for origin/<ref> in status/update/reset/merge:
plain rev-parse echoes the ref name to stdout on failure, producing a
fake remote head ('origin/main' string) that bypassed the empty guards.

Tests: status ahead/behind/up-to-date/diverged + missing-ref regression.

Author: lpb-docs

scripts/lpb-config

@@ -298,7 +298,7 @@ def cmd_status(agent_dir: str | Path, remote: str, ref: str, cons: Console) -> i
         cons.warn("No remote configured")
         return 0
 
-    remote_head = git(agent_dir, "rev-parse", f"origin/{ref}")[0].strip()
+    remote_head = git(agent_dir, "rev-parse", "--verify", f"origin/{ref}")[0].strip()
     if remote_head:
         cons.info(f"Remote:      {remote_head[:8]} origin/{ref} (last fetch)")
 
@@ -311,11 +311,28 @@ def cmd_status(agent_dir: str | Path, remote: str, ref: str, cons: Console) -> i
         cons.info("Working tree: clean")
 
     if remote_head:
-        _, _, code = git(agent_dir, "merge-base", "--is-ancestor", cur, remote_head)
-        if code == 0:
-            cons.info("Status:      up to date (or ahead)")
+        out, _, code = git(agent_dir, "rev-list", "--left-right", "--count",
+                           f"HEAD...origin/{ref}")
+        if code:
+            cons.warn(f"Status:      could not compare with origin/{ref}")
         else:
-            cons.warn("Status:      behind remote — run 'lpb-config update' to fetch")
+            parts = out.split()
+            ahead_n = int(parts[0]) if len(parts) > 0 else 0
+            behind_n = int(parts[1]) if len(parts) > 1 else 0
+            if ahead_n == 0 and behind_n == 0:
+                cons.info(f"Status:      up to date with origin/{ref}")
+            elif ahead_n == 0:
+                cons.warn(f"Status:      behind origin/{ref} by {behind_n} — "
+                          f"run 'lpb-config update' to fetch")
+            elif behind_n == 0:
+                cons.info(f"Status:      ahead of origin/{ref} by {ahead_n} "
+                          f"(unpushed commit(s))")
+            else:
+                cons.warn(f"Status:      diverged from origin/{ref} (ahead {ahead_n}, "
+                          f"behind {behind_n}) — run 'lpb-config merge'")
+    else:
+        cons.warn(f"Status:      origin/{ref} not found locally — "
+                  f"run 'lpb-config update' to fetch")
     return 0
 
 
@@ -334,7 +351,7 @@ def cmd_update(agent_dir: str | Path, remote: str, ref: str, cons: Console) -> i
         cons.error(f"Failed to fetch from {remote}: {err.strip() or out.strip()}")
         return 1
 
-    remote_head = git(agent_dir, "rev-parse", f"origin/{ref}")[0].strip()
+    remote_head = git(agent_dir, "rev-parse", "--verify", f"origin/{ref}")[0].strip()
     cur_head = git(agent_dir, "rev-parse", "HEAD")[0].strip()
     if remote_head == cur_head:
         cons.info("Already up to date.")
@@ -387,7 +404,7 @@ def cmd_reset(
 
     cons.warn(f"This will destroy ALL local changes in {agent_dir}.")
     cons.raw(f"  Current: {head_short(agent_dir)}")
-    remote_head = git(agent_dir, "rev-parse", f"origin/{ref}")[0].strip()[:8]
+    remote_head = git(agent_dir, "rev-parse", "--verify", f"origin/{ref}")[0].strip()[:8]
     cons.raw(f"  Remote:  {remote_head}")
 
     if not force and not confirm("  Continue?", default=False, inp=inp):
@@ -422,7 +439,7 @@ def cmd_merge(agent_dir: str | Path, remote: str, ref: str, cons: Console) -> in
     cons.info(f"Fetching latest from {remote}...")
     git(agent_dir, "fetch", "origin", ref)
 
-    remote_head = git(agent_dir, "rev-parse", f"origin/{ref}")[0].strip()
+    remote_head = git(agent_dir, "rev-parse", "--verify", f"origin/{ref}")[0].strip()
     cur_head = git(agent_dir, "rev-parse", "HEAD")[0].strip()
     if remote_head == cur_head:
         cons.info("Already up to date.")

scripts/test_localpibox_config.py

@@ -141,6 +141,79 @@ def test_lpb_config_status_states(tmpdir):
     assert "No config repo" in (out2.getvalue() + err2.getvalue())
 
 
+def _status_text(tmpdir, agent, remote):
+    out, err = io.StringIO(), io.StringIO()
+    cons = log_mod.Console(color=False, out=out, err=err)
+    assert lc.cmd_status(agent, str(remote), "main", cons) == 0
+    return out.getvalue() + err.getvalue()
+
+
+def test_lpb_config_status_ahead_not_behind(tmpdir):
+    """Local commits not pushed must report ahead, not 'behind remote'."""
+    remote = _setup_git_remote(tmpdir)
+    agent = tmpdir / "agent"
+    lc.cmd_update(agent, str(remote), "main", _quiet_console())
+    (agent / "f").write_text("local only")
+    subprocess.run(["git", "-C", str(agent), "config", "user.email", "t@t"], check=True)
+    subprocess.run(["git", "-C", str(agent), "config", "user.name", "t"], check=True)
+    subprocess.run(["git", "-C", str(agent), "commit", "-qam", "local"], check=True)
+    text = _status_text(tmpdir, agent, remote)
+    assert "ahead of origin/main by 1" in text
+    assert "behind" not in text
+
+
+def test_lpb_config_status_behind(tmpdir):
+    remote = _setup_git_remote(tmpdir)
+    agent = tmpdir / "agent"
+    lc.cmd_update(agent, str(remote), "main", _quiet_console())
+    _push_commit(tmpdir / "work", "two", "two")
+    subprocess.run(["git", "-C", str(agent), "fetch", "-q", "origin", "main"], check=True)
+    text = _status_text(tmpdir, agent, remote)
+    assert "behind origin/main by 1" in text
+    assert "run 'lpb-config update'" in text
+    assert "ahead" not in text
+
+
+def test_lpb_config_status_up_to_date(tmpdir):
+    remote = _setup_git_remote(tmpdir)
+    agent = tmpdir / "agent"
+    lc.cmd_update(agent, str(remote), "main", _quiet_console())
+    text = _status_text(tmpdir, agent, remote)
+    assert "up to date with origin/main" in text
+
+
+def test_lpb_config_status_missing_remote_ref(tmpdir):
+    """origin/<ref> not fetched locally: no fake remote head, no crash, no 'behind'."""
+    remote = _setup_git_remote(tmpdir)
+    agent = tmpdir / "agent"
+    # .git present but no origin ref at all (ref name the remote doesn't have)
+    agent.mkdir()
+    subprocess.run(["git", "-C", str(agent), "init", "-q", "-b", "main"], check=True)
+    subprocess.run(["git", "-C", str(agent), "remote", "add", "origin", str(remote)], check=True)
+    subprocess.run(["git", "-C", str(agent), "config", "user.email", "t@t"], check=True)
+    subprocess.run(["git", "-C", str(agent), "config", "user.name", "t"], check=True)
+    (agent / "f").write_text("x")
+    subprocess.run(["git", "-C", str(agent), "add", "."], check=True)
+    subprocess.run(["git", "-C", str(agent), "commit", "-qm", "x"], check=True)
+    text = _status_text(tmpdir, agent, remote)
+    assert "behind" not in text
+    assert "not found locally" in text
+
+
+def test_lpb_config_status_diverged(tmpdir):
+    remote = _setup_git_remote(tmpdir)
+    agent = tmpdir / "agent"
+    lc.cmd_update(agent, str(remote), "main", _quiet_console())
+    (agent / "f").write_text("local only")
+    subprocess.run(["git", "-C", str(agent), "config", "user.email", "t@t"], check=True)
+    subprocess.run(["git", "-C", str(agent), "config", "user.name", "t"], check=True)
+    subprocess.run(["git", "-C", str(agent), "commit", "-qam", "local"], check=True)
+    _push_commit(tmpdir / "work", "remote", "remote")
+    subprocess.run(["git", "-C", str(agent), "fetch", "-q", "origin", "main"], check=True)
+    text = _status_text(tmpdir, agent, remote)
+    assert "diverged" in text and "ahead 1" in text and "behind 1" in text
+
+
 def test_lpb_config_merge_uptodate(tmpdir):
     remote = _setup_git_remote(tmpdir)
     agent = tmpdir / "agent"