implemented help() using pydoc.Helper and external pager

Trundle · Trundle · commit 5929cc3b6bb5 · 2009-06-03T11:19:29.000+02:00
diff --git a/bpython/_internal.py b/bpython/_internal.py
@@ -1,108 +1,24 @@
 import pydoc
-import textwrap
 import sys
-import cStringIO
 
-# window has to be a global so that the main bpython.py can load it and
-# alter its state and share it with the interpreter being used for the
-# actual user input, I couldn't think of another way of doing this.
-window = None
+from bpython.pager import page
 
+# Ugly monkeypatching
+pydoc.pager = page
 
-def _help(obj):
-    """Wrapper for the regular help() function but with a ghetto
-    PAGER since curses + less = :(
-    As per the vanilla help(), this function special-cases for str,
-    so you can do help('isinstance') or help(isinstance) and get the
-    same result.
-    """
-    io = cStringIO.StringIO()
-    doc = pydoc.TextDoc()
-    helper = pydoc.Helper(None, io)
 
-    rows, columns = window.getmaxyx()
-    rows -= 3
-    columns -= 1
-    output = None
+class _Helper(object):
+    def __init__(self):
+        self.helper = pydoc.Helper(sys.stdin, sys.stdout)
 
-#   Copied and pasted from Lib/pydoc.py and fiddled with
-#   so it works fine with bpython. As far as I can tell
-#   the bpython help is no compliant with the vanilla help.
-#   Please let me know if you find this to be untrue.
-    if type(obj) is type(''):
-        if obj == 'help':
-            helper.intro()
-        elif obj == 'keywords':
-            helper.listkeywords()
-        elif obj == 'topics':
-            helper.listtopics()
-        elif obj == 'modules':
-            helper.listmodules()
-        elif obj[:8] == 'modules ':
-            helper.listmodules(split(obj)[1])
-        elif obj in helper.keywords:
-            helper.showtopic(obj)
-        elif obj in helper.topics:
-            helper.showtopic(obj)
-        elif obj:
-            output = doc.document(eval(obj))
-#######################
+    def __repr__(self):
+        return ("Type help() for interactive help, "
+                "or help(object) for help about object.")
 
-    else:
-        output = doc.document(obj)
-        if not output:
-            output = "No help found for %s" % (obj, )
-            return
+    def __call__(self, *args, **kwargs):
+        self.helper(*args, **kwargs)
 
-    if output is None:
-        output = io.getvalue()
-        io.close()
+_help = _Helper()
 
-    if not output:
-        return
-
-    output = output.replace('\t', '    ')
-
-    if '\n' in output:
-        output = output.replace('\n\n', '\n')
-        output = output.split('\n')
-    else:
-        output = [output]
-
-    paragraphs = []
-    for o in output:
-        paragraphs.append(textwrap.wrap(o, columns))
-
-    i = 0
-    for j, paragraph in enumerate(paragraphs):
-        for line in paragraph:
-            sys.stdout.write(line + '\n')
-            i += 1
-# This is a little unclear, but it just waits for a
-# keypress when the a page worth of text has been
-# displayed and returns if 'q' is pressed:
-            if not i % rows and not wait_for_key():
-                return
-
-
-def wait_for_key():
-    """Block until a key is pressed for the ghetto paging."""
-
-    q = True
-    window.addstr("Press any key, q to cancel.")
-    while True:
-        c = window.getch()
-        if c and c == ord('q'):
-            q = False
-        if c:
-            break
-    clear_line()
-    return q
-
-
-def clear_line():
-    y = window.getyx()[0]
-    window.move(y, 0)
-    window.clrtoeol()
 
 # vim: sw=4 ts=4 sts=4 ai et
diff --git a/bpython/cli.py b/bpython/cli.py
@@ -997,10 +997,8 @@ def repl(self):
             f.close()
             self.interp.runcode(code_obj)
 
-# The regular help() function uses PAGER to display the help, which
-# screws with bpython.
-        from bpython import _internal
-        _internal.window = self.scr
+# Use our own helper function because Python's will use real stdin and
+# stdout instead of our wrapped
         self.push('from bpython import _internal\n')
         self.push('help = _internal._help')
 
diff --git a/bpython/pager.py b/bpython/pager.py
@@ -0,0 +1,55 @@
+# The MIT License
+#
+# Copyright (c) 2009 Andreas Stuehrk
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+
+import curses
+import errno
+import os
+import subprocess
+import sys
+
+
+def get_pager_command():
+    command = os.environ.get('PAGER')
+    return command
+
+
+def page_internal(data):
+    """A more than dumb pager function."""
+    sys.stdout.write(data)
+
+
+def page(data, use_internal=False):
+    command = get_pager_command()
+    if not command or use_internal:
+        page_internal(data)
+    else:
+        curses.endwin()
+        popen = subprocess.Popen([command], stdin=subprocess.PIPE)
+        try:
+            popen.stdin.write(data)
+            popen.stdin.close()
+        except OSError, e:
+            if e.errno != errno.EPIPE:
+                raise
+        popen.wait()
+        curses.doupdate()
