pr: commit worktree changes before push; fix merge/pr order docs

POST /tasks/{id}/pr used to push the branch as-is, so uncommitted
worktree changes never reached the PR (empty diff). Now, after all
skip checks pass, the endpoint commits the worktree on host/<task>
(guarded: refuses when the worktree is on another branch), cleans
__pycache__/*.pyc like host.py merge does, and falls back to the
cloud identity when no git identity is configured. Nothing-to-commit
proceeds. Docs corrected: PR comes after status-merge and before
any local git merge (which deletes branch+worktree).

cloud/tests/test_cloud_dispatch_pr.py

@@ -140,6 +140,12 @@ class _ServerCase(unittest.TestCase):
                 if remote_fail:
                     return _result(1, "", "no remote")
                 return _result(0, "https://example.com/repo.git\n")
+            if "branch" in cmd:
+                # 假 worktree 正好在自己的 host/<任务名> 分支上：
+                # worktree 目录名就是任务 id（见 _worktree）。
+                return _result(0, "host/%s\n" % os.path.basename(cwd or ""))
+            if "add" in cmd or "commit" in cmd:
+                return _result(0, "")
             if "push" in cmd:
                 if push_fail:
                     return _result(1, "", "push rejected")

cloud/tests/test_pr_commit.py

@@ -0,0 +1,158 @@
+"""pr.py 提交步骤单测：push 之前先把 worktree 改动提交到分支。
+
+只用标准库，不联网、不跑真实 git/gh：git/gh 一律用假 runner
+注入；worktree 用真实临时目录，只为验证 __pycache__ / *.pyc
+清理（可再生的缓存）真的删、普通文件不动。
+"""
+
+import os
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+from types import SimpleNamespace
+
+try:
+    from cloud.pr import PrStepError, create_task_pr
+except ImportError:
+    sys.path.insert(0, str(Path(__file__).resolve().parents[2]))
+    from cloud.pr import PrStepError, create_task_pr
+
+
+def _result(returncode=0, stdout="", stderr=""):
+    return SimpleNamespace(returncode=returncode, stdout=stdout,
+                           stderr=stderr)
+
+
+class _Rec:
+    """记录命令的假 runner：git/gh 分开注入，commit 行为可配。"""
+
+    def __init__(self, branch="host/t1", commit="ok"):
+        self.calls = []
+        self.branch = branch
+        self.commit = commit  # ok | nothing | fail | no-identity | add-fail
+
+    def git(self, cmd, cwd):
+        self.calls.append(list(cmd))
+        if "remote" in cmd:
+            return _result(0, "https://example.com/repo.git\n")
+        if "branch" in cmd:
+            return _result(0, self.branch + "\n")
+        if "add" in cmd:
+            if self.commit == "add-fail":
+                return _result(1, "", "add failed")
+            return _result(0, "")
+        if "commit" in cmd:
+            if "-c" in cmd:
+                return _result(0, "")
+            if self.commit == "nothing":
+                return _result(1, "",
+                               "nothing to commit, working tree clean")
+            if self.commit == "fail":
+                return _result(1, "", "fatal: commit exploded")
+            if self.commit == "no-identity":
+                return _result(1, "",
+                               "Please tell me who you are")
+            return _result(0, "")
+        if "push" in cmd:
+            return _result(0, "")
+        return _result(0, "")
+
+    def gh(self, cmd, cwd):
+        self.calls.append(list(cmd))
+        if cmd[:2] == ["gh", "auth"]:
+            return _result(0, "", "")
+        if cmd[:2] == ["gh", "pr"]:
+            return _result(0, "https://example.com/repo/pull/7\n")
+        return _result(0, "")
+
+    def kinds(self):
+        """git 命令按出现顺序归类：branch/add/commit/push。"""
+        out = []
+        for cmd in self.calls:
+            if cmd[:1] == ["git"]:
+                for k in ("branch", "add", "commit", "push"):
+                    if k in cmd:
+                        out.append(k)
+                        break
+        return out
+
+
+class PrCommitTestCase(unittest.TestCase):
+    def setUp(self):
+        self.tmp = tempfile.TemporaryDirectory()
+        self.wt = os.path.join(self.tmp.name, "t1")
+        os.makedirs(self.wt)
+
+    def tearDown(self):
+        self.tmp.cleanup()
+
+    def _run(self, rec):
+        return create_task_pr(
+            "t1", 1, worktrees_root=self.tmp.name,
+            git_runner=rec.git, gh_runner=rec.gh, gh_which="gh")
+
+    def test_commit_before_push_and_pycache_cleaned(self):
+        with open(os.path.join(self.wt, "file.txt"), "w") as f:
+            f.write("x")
+        cache = os.path.join(self.wt, "__pycache__")
+        os.makedirs(cache)
+        with open(os.path.join(cache, "x.pyc"), "wb") as f:
+            f.write(b"\0")
+        with open(os.path.join(self.wt, "stale.pyc"), "wb") as f:
+            f.write(b"\0")
+        rec = _Rec()
+        res = self._run(rec)
+        self.assertEqual(res["pr_url"], "https://example.com/repo/pull/7")
+        self.assertEqual(res["branch"], "host/t1")
+        kinds = rec.kinds()
+        self.assertLess(kinds.index("branch"), kinds.index("add"))
+        self.assertLess(kinds.index("add"), kinds.index("commit"))
+        self.assertLess(kinds.index("commit"), kinds.index("push"))
+        commit_cmd = [c for c in rec.calls if "commit" in c][0]
+        self.assertIn("cloud: t1", commit_cmd)
+        self.assertFalse(os.path.exists(cache))
+        self.assertFalse(os.path.exists(os.path.join(self.wt, "stale.pyc")))
+        self.assertTrue(os.path.exists(os.path.join(self.wt, "file.txt")))
+
+    def test_nothing_to_commit_proceeds_to_push(self):
+        rec = _Rec(commit="nothing")
+        res = self._run(rec)
+        self.assertEqual(res["pr_number"], 7)
+        self.assertIn("push", rec.kinds())
+
+    def test_wrong_branch_fails_commit_without_push(self):
+        rec = _Rec(branch="main")
+        with self.assertRaises(PrStepError) as ctx:
+            self._run(rec)
+        self.assertEqual(ctx.exception.step, "commit")
+        self.assertNotIn("push", rec.kinds())
+        self.assertNotIn("commit", rec.kinds())
+
+    def test_commit_failure_is_commit_step_without_push(self):
+        rec = _Rec(commit="fail")
+        with self.assertRaises(PrStepError) as ctx:
+            self._run(rec)
+        self.assertEqual(ctx.exception.step, "commit")
+        self.assertNotIn("push", rec.kinds())
+
+    def test_add_failure_is_commit_step_without_push(self):
+        rec = _Rec(commit="add-fail")
+        with self.assertRaises(PrStepError) as ctx:
+            self._run(rec)
+        self.assertEqual(ctx.exception.step, "commit")
+        self.assertNotIn("push", rec.kinds())
+
+    def test_identity_fallback_retries_with_cloud_identity(self):
+        rec = _Rec(commit="no-identity")
+        res = self._run(rec)
+        self.assertEqual(res["pr_number"], 7)
+        commits = [c for c in rec.calls if "commit" in c]
+        self.assertEqual(len(commits), 2)
+        self.assertIn("-c", commits[1])
+        self.assertIn("user.name=cloud", commits[1])
+        self.assertIn("push", rec.kinds())
+
+
+if __name__ == "__main__":
+    unittest.main()