#9279: remove the pdb.doc file, put its contents in pdb.__doc__. Also sync this and the pdb docs, introduce a new directive for pdb commands and a role to link to them.

2025-08-04 08:59:19 +00:00 · 2010-07-18 10:11:03 +00:00 · 2010-07-18 10:11:03 +00:00 · 02053ee3b9
commit 02053ee3b9
parent 1b3c262027
5 changed files with 403 additions and 337 deletions
--- a/Lib/pdb.py
+++ b/Lib/pdb.py
@ -1,8 +1,217 @@
 #! /usr/bin/env python3

-"""A Python debugger."""
+"""
+The Python Debugger Pdb
+=======================

-# (See pdb.doc for documentation.)
+To use the debugger in its simplest form:
+
+        >>> import pdb
+        >>> pdb.run('<a statement>')
+
+The debugger's prompt is '(Pdb) '.  This will stop in the first
+function call in <a statement>.
+
+Alternatively, if a statement terminated with an unhandled exception,
+you can use pdb's post-mortem facility to inspect the contents of the
+traceback:
+
+        >>> <a statement>
+        <exception traceback>
+        >>> import pdb
+        >>> pdb.pm()
+
+The commands recognized by the debugger are listed in the next
+section.  Most can be abbreviated as indicated; e.g., h(elp) means
+that 'help' can be typed as 'h' or 'help' (but not as 'he' or 'hel',
+nor as 'H' or 'Help' or 'HELP').  Optional arguments are enclosed in
+square brackets.  Alternatives in the command syntax are separated
+by a vertical bar (|).
+
+A blank line repeats the previous command literally, except for
+'list', where it lists the next 11 lines.
+
+Commands that the debugger doesn't recognize are assumed to be Python
+statements and are executed in the context of the program being
+debugged.  Python statements can also be prefixed with an exclamation
+point ('!').  This is a powerful way to inspect the program being
+debugged; it is even possible to change variables or call functions.
+When an exception occurs in such a statement, the exception name is
+printed but the debugger's state is not changed.
+
+The debugger supports aliases, which can save typing.  And aliases can
+have parameters (see the alias help entry) which allows one a certain
+level of adaptability to the context under examination.
+
+Multiple commands may be entered on a single line, separated by the
+pair ';;'.  No intelligence is applied to separating the commands; the
+input is split at the first ';;', even if it is in the middle of a
+quoted string.
+
+If a file ".pdbrc" exists in your home directory or in the current
+directory, it is read in and executed as if it had been typed at the
+debugger prompt.  This is particularly useful for aliases.  If both
+files exist, the one in the home directory is read first and aliases
+defined there can be overriden by the local file.
+
+Aside from aliases, the debugger is not directly programmable; but it
+is implemented as a class from which you can derive your own debugger
+class, which you can make as fancy as you like.
+
+
+Debugger commands
+=================
+
+h(elp)
+        Without argument, print the list of available commands.  With
+        a command name as argument, print help about that command.
+
+w(here)
+        Print a stack trace, with the most recent frame at the bottom.
+        An arrow indicates the "current frame", which determines the
+        context of most commands.
+
+d(own) [ count ]
+        Move the current frame count (default one) levels down in the
+        stack trace (to a newer frame).
+
+u(p) [ count ]
+        Move the current frame count (default one) levels up in the
+        stack trace (to an older frame).
+
+b(reak) [ ([filename:]lineno | function) [, condition] ]
+        With a filename:lineno argument, set a break there.  If
+        filename is omitted, use the current file.  With a function
+        name, set a break at the first executable line of that
+        function.  Without argument, list all breaks.  Each breakpoint
+        is assigned a number to which all the other breakpoint
+        commands refer.
+
+        The condition argument, if present, is a string which must
+        evaluate to true in order for the breakpoint to be honored.
+
+tbreak [ ([filename:]lineno | function) [, condition] ]
+        Temporary breakpoint, which is removed automatically when it
+        is first hit.  The arguments are the same as for break.
+
+cl(ear) [bpnumber [bpnumber ...] ]
+        With a space separated list of breakpoint numbers, clear those
+        breakpoints.  Without argument, clear all breaks (but first
+        ask confirmation).
+
+disable bpnumber [bpnumber ...]
+        Disable the breakpoints given as a space separated list of
+        breakpoint numbers.  Disabling a breakpoint means it cannot
+        cause the program to stop execution, but unlike clearing a
+        breakpoint, it remains in the list of breakpoints and can be
+        (re-)enabled.
+
+enable bpnumber [bpnumber ...]
+        Enable the breakpoints specified.
+
+ignore bpnumber [count]
+        Set the ignore count for the given breakpoint number.  If
+        count is omitted, the ignore count is set to 0.  A breakpoint
+        becomes active when the ignore count is zero.  When non-zero,
+        the count is decremented each time the breakpoint is reached
+        and the breakpoint is not disabled and any associated
+        condition evaluates to true.
+
+condition bpnumber [condition]
+        Set a new condition for the breakpoint, an expression which
+        must evaluate to true before the breakpoint is honored.  If
+        condition is absent, any existing condition is removed; i.e.,
+        the breakpoint is made unconditional.
+
+commands [bpnumber]
+        Specify a list of commands for the breakpoint.  Type a line
+        containing just 'end' to terminate the commands.  The commands
+        are executed when the breakpoint is hit.
+
+        With no breakpoint number argument, refers to the last
+        breakpoint set.
+
+s(tep)
+        Execute the current line, stop at the first possible occasion
+        (either in a function that is called or in the current
+        function).
+
+n(ext)
+        Continue execution until the next line in the current function
+        is reached or it returns.
+
+unt(il)
+        Continue execution until the line with a number greater than
+        the current one is reached or until the current frame returns.
+
+r(eturn)
+        Continue execution until the current function returns.
+
+run [args...]
+        Restart the debugged python program. If a string is supplied
+        it is splitted with "shlex", and the result is used as the new
+        sys.argv.  History, breakpoints, actions and debugger options
+        are preserved.  "restart" is an alias for "run".
+
+c(ont(inue))
+        Continue execution, only stop when a breakpoint is encountered.
+
+l(ist) [first [,last]]
+        List source code for the current file.
+        Without arguments, list 11 lines around the current line
+        or continue the previous listing.
+        With one argument, list 11 lines starting at that line.
+        With two arguments, list the given range;
+        if the second argument is less than the first, it is a count.
+
+a(rgs)
+        Print the argument list of the current function.
+
+p expression
+        Print the value of the expression.
+
+(!) statement
+        Execute the (one-line) statement in the context of the current
+        stack frame.  The exclamation point can be omitted unless the
+        first word of the statement resembles a debugger command.  To
+        assign to a global variable you must always prefix the command
+        with a 'global' command, e.g.:
+        (Pdb) global list_options; list_options = ['-l']
+        (Pdb)
+
+
+whatis arg
+        Print the type of the argument.
+
+alias [name [command]]
+        Creates an alias called 'name' that executes 'command'.  The
+        command must *not* be enclosed in quotes.  Replaceable
+        parameters can be indicated by %1, %2, and so on, while %* is
+        replaced by all the parameters.  If no command is given, the
+        current alias for name is shown. If no name is given, all
+        aliases are listed.
+
+        Aliases may be nested and can contain anything that can be
+        legally typed at the pdb prompt.  Note!  You *can* override
+        internal pdb commands with aliases!  Those internal commands
+        are then hidden until the alias is removed.  Aliasing is
+        recursively applied to the first word of the command line; all
+        other words in the line are left alone.
+
+        As an example, here are two useful aliases (especially when
+        placed in the .pdbrc file):
+
+        # Print instance variables (usage "pi classInst")
+        alias pi for k in %1.__dict__.keys(): print "%1.",k,"=",%1.__dict__[k]
+        # Print instance variables in self
+        alias ps pi self
+
+unalias name
+        Delete the specified alias.
+
+q(uit)
+        Quit from the debugger. The program being executed is aborted.
+"""

 import sys
 import linecache
@ -905,7 +1114,7 @@ class Pdb(bdb.Bdb, cmd.Cmd):
                                                     prompt_prefix), file=self.stdout)


-    # Help methods (derived from pdb.doc)
+    # Help methods (derived from docstring)

    def help_help(self):
        self.help_h()
@ -1281,15 +1490,8 @@ def test():

 # print help
 def help():
-    for dirname in sys.path:
-        fullname = os.path.join(dirname, 'pdb.doc')
-        if os.path.exists(fullname):
-            sts = os.system('${PAGER-more} '+fullname)
-            if sts: print('*** Pager exit status:', sts)
-            break
-    else:
-        print('Sorry, can\'t find the help file "pdb.doc"', end=' ')
-        print('along the Python search path')
+    import pydoc
+    pydoc.pager(__doc__)

 def main():
    if not sys.argv[1:] or sys.argv[1] in ("--help", "-h"):