bug, refactor, test: make pragma history_length work interactively

history_length could be set interactively, but it was never used to set
readline/pyreadline3's internal state. Using the pragma setting on the
roundup-admin command line did set readline's state.

Also refactored 2 calls to self.readline.get_current_history_length()
into one call and storing in a variable. Also changed method for
creating history strings for printing.

Tests added for history_length pragma on cli and interactive use.

Added test for exiting roundup-admin with EOF on input.

Added test for 'readline nosuchdirective' error case.

Added test to readline with a command directive to set an internal
variable. This last one has no real test to see if it was successful
because I can't emulate a real keyboard/tty which is needed to test.

Author: rouilj

CHANGES.txt

@@ -26,6 +26,9 @@ Fixed:
 - cleaned up repo. Close obsolete branches and close a split head due
   to an identical merge intwo different workicng copies. (John
   Rouillard)
+- in roundup-admin, using 'pragma history_length interactively now
+  sets readline history length. Using -P history_length=10 on the
+  command line always worked. (John Rouillard)
 
 Features:
 

roundup/admin.py

@@ -1821,6 +1821,11 @@ def do_pragma(self, args):
                              type(self.settings[setting]).__name__)
         self.settings[setting] = value
 
+        # history_length has to be pushed to readline to have any effect.
+        if setting == "history_length":
+            self.readline.set_history_length(
+                self.settings['history_length'])
+
     def do_readline(self, args):
         ''"""Usage: readline initrc_line | 'emacs' | 'history' | 'reload' | 'vi'
 
@@ -1881,13 +1886,12 @@ def do_readline(self, args):
                 self.readline.parse_and_bind("set editing-mode emacs")
                 print(_("Enabled emacs mode."))
             elif args[0] == "history":
-                print("history size",
-                      self.readline.get_current_history_length())
+                history_size = self.readline.get_current_history_length()
+                print("history size", history_size)
                 print('\n'.join([
-                    str("%3d " % (i + 1) +
+                    "%3d %s" % ((i + 1),
                         self.readline.get_history_item(i + 1))
-                    for i in range(
-                            self.readline.get_current_history_length())
+                    for i in range(history_size)
                 ]))
             elif args[0] == "reload":
                 try:

test/test_admin.py

@@ -184,6 +184,31 @@ def testBasicInteractive(self):
 
         AdminTool.my_input = orig_input
 
+        # test EOF exit
+        inputs = ["help"]
+        
+        self._monkeypatch.setattr(
+            'sys.stdin',
+            io.StringIO("\n".join(inputs)))
+
+        # preserve directory self.install_init()
+        self.admin=AdminTool()
+
+        # disable all features
+        self.admin.settings['history_features'] = 7
+        sys.argv=['main', '-i', self.dirname]
+        
+        with captured_output() as (out, err):
+            ret = self.admin.main()
+        out = out.getvalue().strip().split('\n')
+        
+        print(ret)
+        self.assertTrue(ret == 0)
+
+        # 4 includes 2 commands in saved history
+        expected = 'roundup> exit...'
+        self.assertIn(expected, out)
+
     def testGet(self):
         ''' Note the tests will fail if you run this under pdb.
             the context managers capture the pdb prompts and this screws
@@ -1947,6 +1972,120 @@ def testReadline(self):
 
         self.assertIn(expected, out)
 
+        # --- test 3,4 - make sure readline gets history_length pragma.
+        #   test CLI and interactive.
+        
+        inputs = ["pragma list", "q"]
+        
+        self._monkeypatch.setattr(
+            'sys.stdin',
+            io.StringIO("\n".join(inputs)))
+
+        self.install_init()
+        self.admin=AdminTool()
+
+        # disable all config/history
+        self.admin.settings['history_features'] = 7
+        sys.argv=['main', '-i', self.dirname, '-P', 'history_length=11']
+        
+        with captured_output() as (out, err):
+            ret = self.admin.main()
+            out = out.getvalue().strip().split('\n')
+            
+        print(ret)
+        self.assertTrue(ret == 0)
+        self.assertEqual(self.admin.readline.get_history_length(),
+                         11)
+
+        # 4
+        inputs = ["pragma history_length=17", "q"]
+        
+        self._monkeypatch.setattr(
+            'sys.stdin',
+            io.StringIO("\n".join(inputs)))
+
+        self.install_init()
+        self.admin=AdminTool()
+
+        # disable all config/history
+        self.admin.settings['history_features'] = 7
+        # keep pragma in CLI. Make sure it's overridden by interactive
+        sys.argv=['main', '-i', self.dirname, '-P', 'history_length=11']
+        
+        with captured_output() as (out, err):
+            ret = self.admin.main()
+            out = out.getvalue().strip().split('\n')
+            
+        print(ret)
+        self.assertTrue(ret == 0)
+        # should not be 11.
+        self.assertEqual(self.admin.readline.get_history_length(),
+                         17)
+
+        # --- test 5 invalid single word parameter
+        
+        inputs = ["readline nosuchdirective", "q"]
+        
+        self._monkeypatch.setattr(
+            'sys.stdin',
+            io.StringIO("\n".join(inputs)))
+
+        self.install_init()
+        self.admin=AdminTool()
+
+        # disable loading and saving history
+        self.admin.settings['history_features'] = 3
+        sys.argv=['main', '-i', self.dirname]
+        
+        with captured_output() as (out, err):
+            ret = self.admin.main()
+            out = out.getvalue().strip().split('\n')
+            
+        print(ret)
+        self.assertTrue(ret == 0)
+
+        expected = ('roundup> Unknown readline parameter nosuchdirective')
+        
+        self.assertIn(expected, out)
+
+        # --- test 6 set keystroke command.
+        # FIXME: unable to test key binding/setting actually works.
+        #
+        #        No errors seem to come back from readline or
+        #        pyreadline3 even when the keybinding makes no
+        #        sense. Errors are only reported when reading
+        #        from init file. Using "set answer 42" does print
+        #        'readline: answer: unknown variable name' when
+        #        attached to tty/pty and interactive, but not
+        #        inside test case. Pyreadline3 doesn't
+        #        report errors at all.
+        #
+        #        Even if I set a keybidning, I can't invoke it
+        #        because I am not running inside a pty, so
+        #        editing is disabled and I have no way to
+        #        simulate keyboard keystrokes for readline to act
+        #        upon.
+        
+        inputs = ['readline set meaning 42', "q"]
+        
+        self._monkeypatch.setattr(
+            'sys.stdin',
+            io.StringIO("\n".join(inputs)))
+
+        self.install_init()
+        self.admin=AdminTool()
+
+        # disable loading and saving history
+        self.admin.settings['history_features'] = 3
+        sys.argv=['main', '-i', self.dirname]
+        
+        with captured_output() as (out, err):
+            ret = self.admin.main()
+            out = out.getvalue().strip().split('\n')
+            
+        print(ret)
+        self.assertTrue(ret == 0)
+
         # === cleanup
         if original_home:
             os.environ['HOME'] = original_home