fix: headless login URL + friendly next/show with no attempt

tanco/driver.py

@@ -2,25 +2,25 @@
 """
 command-line driver for tanco client.
 """
 import argparse
 import asyncio
 import cmd as cmdlib
 import os
 import shlex
 import sqlite3
 import subprocess
 import sys
 import webbrowser
 import pprint
 
 import jwt as jwtlib
 import websockets as w
 
 from . import database as db
 from . import model as m
 from . import orgtest, runner
 from .client import TancoClient
 from .model import Config, TestDescription
 
 class TancoDriver(cmdlib.Cmd):
     prompt = 'tanco> '
@@ -46,7 +46,12 @@
             return
         sid = db.get_server_id(self.client.url)
         pre = self.client.get_pre_token()
-        webbrowser.open(self.client.url + 'auth/login?pre=' + pre)
+        url = self.client.url + 'auth/login?pre=' + pre
+        # Always print the URL so headless / remote users can open it manually.
+        print('Open this URL to log in:')
+        print(url)
+        if not webbrowser.open(url):
+            print('(No browser available; open the URL above in any browser.)')
         jwt = self.client.get_jwt(pre=pre)
         data = jwtlib.JWT().decode(jwt, do_verify=False)  # TODO: verify
         uid = db.uid_from_tokendata(sid, data['authid'], data['username'])
@@ -154,18 +159,18 @@
         num_desc_removed = sum(1 for line in lines if line.strip().startswith(': '))
 
         # Show summary
         has_todo = any(l.strip().lower().startswith('#+todo:') for l in lines)
         print(f'{"Would migrate" if args.check else "Migrating"}: {args.file}')
         print(f'Changes:')
         print(f'  - Add #+tanco-format: 0.2 directive')
         if not has_todo:
             print(f'  - Add #+todo: TODO | DONE TEST directive')
         print(f'  - Migrate {num_tests} tests')
         print(f'  - Remove {num_name_removed} #+name: directives')
         print(f'  - Remove TODO/DONE from test headlines')
         print(f'  - Remove {num_title_removed} = title lines')
         print(f'  - Remove {num_desc_removed} : description lines')
         print(f'  - Move description text to test bodies')
         print()
 
         if args.check:
@@ -229,7 +234,7 @@
             try:
                 arg = self.result[int(arg)]['name']
             except IndexError:
                 print(f"Sorry, challenge number {arg} not found.")
                 return
         if arg == '--local':
             print('starting local challenge.')
@@ -267,7 +272,16 @@
     def do_show(self, arg=None):
         """Show a description of the current test."""
         cfg = runner.load_config()
-        state = db.current_state(cfg.attempt)
+        if not cfg.attempt:
+            print('No active attempt.')
+            print('Use `tanco init` to start a new attempt.')
+            return
+        try:
+            state = db.current_state(cfg.attempt)
+        except IndexError:
+            print('No active attempt.')
+            print('Use `tanco init` to start a new attempt.')
+            return
         if state == 'start':
             print('You have not started the challenge yet.')
             print('Use `tanco check` to make sure your program runs.')
@@ -321,7 +335,16 @@
         # TODO:  double check that all tests pass and repo is clean
 
         cfg = runner.load_config()
-        state = db.current_state(cfg.attempt)
+        if not cfg.attempt:
+            print('No active attempt.')
+            print('Use `tanco init` to start a new attempt.')
+            return
+        try:
+            state = db.current_state(cfg.attempt)
+        except IndexError:
+            print('No active attempt.')
+            print('Use `tanco init` to start a new attempt.')
+            return
         if state == 'done':
             print('You have already completed the challenge!')
             return
@@ -359,13 +382,15 @@
         self.do_show()
 
     def do_spawn(self, _arg):
+        """Spawn the target program as a persistent process"""
         self.target = runner.spawn(runner.load_config())
 
     def ensure_target(self):
         if not self.target:
             self.do_spawn('')
 
     def do_send(self, msg, suppress=False):
+        """Send a message to the target program and print its output"""
         self.ensure_target()
         if msg.endswith(self.end_cmd): msg = msg[:-1]
         self.target.stdin.write(msg + f'\n{self.end_cmd}\n')

tests/test_basic.py

@@ -73,3 +73,79 @@ def test_valid_test_names_accepted(self):
         self.assertEqual(len(c.tests), 2)
         self.assertEqual(c.tests[0].name, 'foo.bar-1')
         self.assertEqual(c.tests[1].name, 'baz_2.A')
+
+
+
+class DriverNextTest(unittest.TestCase):
+    """Regression: tanco next/show must not IndexError when no attempt is active."""
+
+    def setUp(self) -> None:
+        TANCO_SDB_PATH.unlink(missing_ok=True)
+        tanco.database.ensure_sdb()
+        with tanco.database.begin() as conn:
+            cur = conn.execute(
+                'insert into servers (url, name, info) values (?, ?, ?)',
+                (TANCO_SERVER, 'fakeserver', 'fake'))
+            sid = cur.lastrowid
+            cur = conn.execute(
+                'insert into users (sid, authid, username) values (?, ?, ?)',
+                (sid, 'fakeauthid', 'fakeuser'))
+            uid = cur.lastrowid
+            conn.execute('insert into tokens (uid, jwt) values (?, ?)', (uid, 'fakejwt'))
+        self._old_cwd = os.getcwd()
+
+    def tearDown(self) -> None:
+        os.chdir(self._old_cwd)
+        TANCO_SDB_PATH.unlink(missing_ok=True)
+
+    def _run_in_empty_project(self, method_name: str) -> str:
+        import io
+        from contextlib import redirect_stdout
+
+        import tanco.driver
+
+        buf = io.StringIO()
+        with tempfile.TemporaryDirectory() as tmp:
+            os.chdir(tmp)
+            d = tanco.driver.TancoDriver()
+            with redirect_stdout(buf):
+                getattr(d, method_name)('')
+            os.chdir(self._old_cwd)
+        return buf.getvalue()
+
+    def test_next_no_active_attempt_prints_friendly_message(self) -> None:
+        out = self._run_in_empty_project('do_next')
+        self.assertIn('No active attempt', out)
+        self.assertIn('tanco init', out)
+
+    def test_show_no_active_attempt_prints_friendly_message(self) -> None:
+        out = self._run_in_empty_project('do_show')
+        self.assertIn('No active attempt', out)
+        self.assertIn('tanco init', out)
+
+    def test_login_prints_oauth_url(self) -> None:
+        import io
+        from contextlib import redirect_stdout
+        from unittest.mock import MagicMock, patch
+
+        import tanco.driver
+
+        d = tanco.driver.TancoDriver()
+        d.client = MagicMock()
+        d.client.whoami.return_value = None
+        d.client.url = 'https://example.test/'
+        d.client.get_pre_token.return_value = 'PRETOKEN'
+        d.client.get_jwt.side_effect = RuntimeError('stop-after-print')
+
+        buf = io.StringIO()
+        with patch('tanco.driver.webbrowser.open', return_value=False) as open_mock, \
+             patch('tanco.driver.db.get_server_id', return_value=1):
+            with redirect_stdout(buf):
+                try:
+                    d.do_login('')
+                except RuntimeError as e:
+                    self.assertEqual(str(e), 'stop-after-print')
+
+        out = buf.getvalue()
+        self.assertIn('https://example.test/auth/login?pre=PRETOKEN', out)
+        open_mock.assert_called_once_with('https://example.test/auth/login?pre=PRETOKEN')