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author | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:24:06 +0300 |
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committer | nkozlovskiy <nmk@ydb.tech> | 2023-09-29 12:41:34 +0300 |
commit | e0e3e1717e3d33762ce61950504f9637a6e669ed (patch) | |
tree | bca3ff6939b10ed60c3d5c12439963a1146b9711 /contrib/python/ipython/py3/IPython/lib/demo.py | |
parent | 38f2c5852db84c7b4d83adfcb009eb61541d1ccd (diff) | |
download | ydb-e0e3e1717e3d33762ce61950504f9637a6e669ed.tar.gz |
add ydb deps
Diffstat (limited to 'contrib/python/ipython/py3/IPython/lib/demo.py')
-rw-r--r-- | contrib/python/ipython/py3/IPython/lib/demo.py | 672 |
1 files changed, 672 insertions, 0 deletions
diff --git a/contrib/python/ipython/py3/IPython/lib/demo.py b/contrib/python/ipython/py3/IPython/lib/demo.py new file mode 100644 index 0000000000..ebffd54abd --- /dev/null +++ b/contrib/python/ipython/py3/IPython/lib/demo.py @@ -0,0 +1,672 @@ +"""Module for interactive demos using IPython. + +This module implements a few classes for running Python scripts interactively +in IPython for demonstrations. With very simple markup (a few tags in +comments), you can control points where the script stops executing and returns +control to IPython. + + +Provided classes +---------------- + +The classes are (see their docstrings for further details): + + - Demo: pure python demos + + - IPythonDemo: demos with input to be processed by IPython as if it had been + typed interactively (so magics work, as well as any other special syntax you + may have added via input prefilters). + + - LineDemo: single-line version of the Demo class. These demos are executed + one line at a time, and require no markup. + + - IPythonLineDemo: IPython version of the LineDemo class (the demo is + executed a line at a time, but processed via IPython). + + - ClearMixin: mixin to make Demo classes with less visual clutter. It + declares an empty marquee and a pre_cmd that clears the screen before each + block (see Subclassing below). + + - ClearDemo, ClearIPDemo: mixin-enabled versions of the Demo and IPythonDemo + classes. + +Inheritance diagram: + +.. inheritance-diagram:: IPython.lib.demo + :parts: 3 + +Subclassing +----------- + +The classes here all include a few methods meant to make customization by +subclassing more convenient. Their docstrings below have some more details: + + - highlight(): format every block and optionally highlight comments and + docstring content. + + - marquee(): generates a marquee to provide visible on-screen markers at each + block start and end. + + - pre_cmd(): run right before the execution of each block. + + - post_cmd(): run right after the execution of each block. If the block + raises an exception, this is NOT called. + + +Operation +--------- + +The file is run in its own empty namespace (though you can pass it a string of +arguments as if in a command line environment, and it will see those as +sys.argv). But at each stop, the global IPython namespace is updated with the +current internal demo namespace, so you can work interactively with the data +accumulated so far. + +By default, each block of code is printed (with syntax highlighting) before +executing it and you have to confirm execution. This is intended to show the +code to an audience first so you can discuss it, and only proceed with +execution once you agree. There are a few tags which allow you to modify this +behavior. + +The supported tags are: + +# <demo> stop + + Defines block boundaries, the points where IPython stops execution of the + file and returns to the interactive prompt. + + You can optionally mark the stop tag with extra dashes before and after the + word 'stop', to help visually distinguish the blocks in a text editor: + + # <demo> --- stop --- + + +# <demo> silent + + Make a block execute silently (and hence automatically). Typically used in + cases where you have some boilerplate or initialization code which you need + executed but do not want to be seen in the demo. + +# <demo> auto + + Make a block execute automatically, but still being printed. Useful for + simple code which does not warrant discussion, since it avoids the extra + manual confirmation. + +# <demo> auto_all + + This tag can _only_ be in the first block, and if given it overrides the + individual auto tags to make the whole demo fully automatic (no block asks + for confirmation). It can also be given at creation time (or the attribute + set later) to override what's in the file. + +While _any_ python file can be run as a Demo instance, if there are no stop +tags the whole file will run in a single block (no different that calling +first %pycat and then %run). The minimal markup to make this useful is to +place a set of stop tags; the other tags are only there to let you fine-tune +the execution. + +This is probably best explained with the simple example file below. You can +copy this into a file named ex_demo.py, and try running it via:: + + from IPython.lib.demo import Demo + d = Demo('ex_demo.py') + d() + +Each time you call the demo object, it runs the next block. The demo object +has a few useful methods for navigation, like again(), edit(), jump(), seek() +and back(). It can be reset for a new run via reset() or reloaded from disk +(in case you've edited the source) via reload(). See their docstrings below. + +Note: To make this simpler to explore, a file called "demo-exercizer.py" has +been added to the "docs/examples/core" directory. Just cd to this directory in +an IPython session, and type:: + + %run demo-exercizer.py + +and then follow the directions. + +Example +------- + +The following is a very simple example of a valid demo file. + +:: + + #################### EXAMPLE DEMO <ex_demo.py> ############################### + '''A simple interactive demo to illustrate the use of IPython's Demo class.''' + + print('Hello, welcome to an interactive IPython demo.') + + # The mark below defines a block boundary, which is a point where IPython will + # stop execution and return to the interactive prompt. The dashes are actually + # optional and used only as a visual aid to clearly separate blocks while + # editing the demo code. + # <demo> stop + + x = 1 + y = 2 + + # <demo> stop + + # the mark below makes this block as silent + # <demo> silent + + print('This is a silent block, which gets executed but not printed.') + + # <demo> stop + # <demo> auto + print('This is an automatic block.') + print('It is executed without asking for confirmation, but printed.') + z = x + y + + print('z =', x) + + # <demo> stop + # This is just another normal block. + print('z is now:', z) + + print('bye!') + ################### END EXAMPLE DEMO <ex_demo.py> ############################ +""" + + +#***************************************************************************** +# Copyright (C) 2005-2006 Fernando Perez. <Fernando.Perez@colorado.edu> +# +# Distributed under the terms of the BSD License. The full license is in +# the file COPYING, distributed as part of this software. +# +#***************************************************************************** + +import os +import re +import shlex +import sys +import pygments +from pathlib import Path + +from IPython.utils.text import marquee +from IPython.utils import openpy +from IPython.utils import py3compat +__all__ = ['Demo','IPythonDemo','LineDemo','IPythonLineDemo','DemoError'] + +class DemoError(Exception): pass + +def re_mark(mark): + return re.compile(r'^\s*#\s+<demo>\s+%s\s*$' % mark,re.MULTILINE) + +class Demo(object): + + re_stop = re_mark(r'-*\s?stop\s?-*') + re_silent = re_mark('silent') + re_auto = re_mark('auto') + re_auto_all = re_mark('auto_all') + + def __init__(self,src,title='',arg_str='',auto_all=None, format_rst=False, + formatter='terminal', style='default'): + """Make a new demo object. To run the demo, simply call the object. + + See the module docstring for full details and an example (you can use + IPython.Demo? in IPython to see it). + + Inputs: + + - src is either a file, or file-like object, or a + string that can be resolved to a filename. + + Optional inputs: + + - title: a string to use as the demo name. Of most use when the demo + you are making comes from an object that has no filename, or if you + want an alternate denotation distinct from the filename. + + - arg_str(''): a string of arguments, internally converted to a list + just like sys.argv, so the demo script can see a similar + environment. + + - auto_all(None): global flag to run all blocks automatically without + confirmation. This attribute overrides the block-level tags and + applies to the whole demo. It is an attribute of the object, and + can be changed at runtime simply by reassigning it to a boolean + value. + + - format_rst(False): a bool to enable comments and doc strings + formatting with pygments rst lexer + + - formatter('terminal'): a string of pygments formatter name to be + used. Useful values for terminals: terminal, terminal256, + terminal16m + + - style('default'): a string of pygments style name to be used. + """ + if hasattr(src, "read"): + # It seems to be a file or a file-like object + self.fname = "from a file-like object" + if title == '': + self.title = "from a file-like object" + else: + self.title = title + else: + # Assume it's a string or something that can be converted to one + self.fname = src + if title == '': + (filepath, filename) = os.path.split(src) + self.title = filename + else: + self.title = title + self.sys_argv = [src] + shlex.split(arg_str) + self.auto_all = auto_all + self.src = src + + try: + ip = get_ipython() # this is in builtins whenever IPython is running + self.inside_ipython = True + except NameError: + self.inside_ipython = False + + if self.inside_ipython: + # get a few things from ipython. While it's a bit ugly design-wise, + # it ensures that things like color scheme and the like are always in + # sync with the ipython mode being used. This class is only meant to + # be used inside ipython anyways, so it's OK. + self.ip_ns = ip.user_ns + self.ip_colorize = ip.pycolorize + self.ip_showtb = ip.showtraceback + self.ip_run_cell = ip.run_cell + self.shell = ip + + self.formatter = pygments.formatters.get_formatter_by_name(formatter, + style=style) + self.python_lexer = pygments.lexers.get_lexer_by_name("py3") + self.format_rst = format_rst + if format_rst: + self.rst_lexer = pygments.lexers.get_lexer_by_name("rst") + + # load user data and initialize data structures + self.reload() + + def fload(self): + """Load file object.""" + # read data and parse into blocks + if hasattr(self, 'fobj') and self.fobj is not None: + self.fobj.close() + if hasattr(self.src, "read"): + # It seems to be a file or a file-like object + self.fobj = self.src + else: + # Assume it's a string or something that can be converted to one + self.fobj = openpy.open(self.fname) + + def reload(self): + """Reload source from disk and initialize state.""" + self.fload() + + self.src = "".join(openpy.strip_encoding_cookie(self.fobj)) + src_b = [b.strip() for b in self.re_stop.split(self.src) if b] + self._silent = [bool(self.re_silent.findall(b)) for b in src_b] + self._auto = [bool(self.re_auto.findall(b)) for b in src_b] + + # if auto_all is not given (def. None), we read it from the file + if self.auto_all is None: + self.auto_all = bool(self.re_auto_all.findall(src_b[0])) + else: + self.auto_all = bool(self.auto_all) + + # Clean the sources from all markup so it doesn't get displayed when + # running the demo + src_blocks = [] + auto_strip = lambda s: self.re_auto.sub('',s) + for i,b in enumerate(src_b): + if self._auto[i]: + src_blocks.append(auto_strip(b)) + else: + src_blocks.append(b) + # remove the auto_all marker + src_blocks[0] = self.re_auto_all.sub('',src_blocks[0]) + + self.nblocks = len(src_blocks) + self.src_blocks = src_blocks + + # also build syntax-highlighted source + self.src_blocks_colored = list(map(self.highlight,self.src_blocks)) + + # ensure clean namespace and seek offset + self.reset() + + def reset(self): + """Reset the namespace and seek pointer to restart the demo""" + self.user_ns = {} + self.finished = False + self.block_index = 0 + + def _validate_index(self,index): + if index<0 or index>=self.nblocks: + raise ValueError('invalid block index %s' % index) + + def _get_index(self,index): + """Get the current block index, validating and checking status. + + Returns None if the demo is finished""" + + if index is None: + if self.finished: + print('Demo finished. Use <demo_name>.reset() if you want to rerun it.') + return None + index = self.block_index + else: + self._validate_index(index) + return index + + def seek(self,index): + """Move the current seek pointer to the given block. + + You can use negative indices to seek from the end, with identical + semantics to those of Python lists.""" + if index<0: + index = self.nblocks + index + self._validate_index(index) + self.block_index = index + self.finished = False + + def back(self,num=1): + """Move the seek pointer back num blocks (default is 1).""" + self.seek(self.block_index-num) + + def jump(self,num=1): + """Jump a given number of blocks relative to the current one. + + The offset can be positive or negative, defaults to 1.""" + self.seek(self.block_index+num) + + def again(self): + """Move the seek pointer back one block and re-execute.""" + self.back(1) + self() + + def edit(self,index=None): + """Edit a block. + + If no number is given, use the last block executed. + + This edits the in-memory copy of the demo, it does NOT modify the + original source file. If you want to do that, simply open the file in + an editor and use reload() when you make changes to the file. This + method is meant to let you change a block during a demonstration for + explanatory purposes, without damaging your original script.""" + + index = self._get_index(index) + if index is None: + return + # decrease the index by one (unless we're at the very beginning), so + # that the default demo.edit() call opens up the sblock we've last run + if index>0: + index -= 1 + + filename = self.shell.mktempfile(self.src_blocks[index]) + self.shell.hooks.editor(filename, 1) + with open(Path(filename), "r", encoding="utf-8") as f: + new_block = f.read() + # update the source and colored block + self.src_blocks[index] = new_block + self.src_blocks_colored[index] = self.highlight(new_block) + self.block_index = index + # call to run with the newly edited index + self() + + def show(self,index=None): + """Show a single block on screen""" + + index = self._get_index(index) + if index is None: + return + + print(self.marquee('<%s> block # %s (%s remaining)' % + (self.title,index,self.nblocks-index-1))) + print(self.src_blocks_colored[index]) + sys.stdout.flush() + + def show_all(self): + """Show entire demo on screen, block by block""" + + fname = self.title + title = self.title + nblocks = self.nblocks + silent = self._silent + marquee = self.marquee + for index,block in enumerate(self.src_blocks_colored): + if silent[index]: + print(marquee('<%s> SILENT block # %s (%s remaining)' % + (title,index,nblocks-index-1))) + else: + print(marquee('<%s> block # %s (%s remaining)' % + (title,index,nblocks-index-1))) + print(block, end=' ') + sys.stdout.flush() + + def run_cell(self,source): + """Execute a string with one or more lines of code""" + + exec(source, self.user_ns) + + def __call__(self,index=None): + """run a block of the demo. + + If index is given, it should be an integer >=1 and <= nblocks. This + means that the calling convention is one off from typical Python + lists. The reason for the inconsistency is that the demo always + prints 'Block n/N, and N is the total, so it would be very odd to use + zero-indexing here.""" + + index = self._get_index(index) + if index is None: + return + try: + marquee = self.marquee + next_block = self.src_blocks[index] + self.block_index += 1 + if self._silent[index]: + print(marquee('Executing silent block # %s (%s remaining)' % + (index,self.nblocks-index-1))) + else: + self.pre_cmd() + self.show(index) + if self.auto_all or self._auto[index]: + print(marquee('output:')) + else: + print(marquee('Press <q> to quit, <Enter> to execute...'), end=' ') + ans = py3compat.input().strip() + if ans: + print(marquee('Block NOT executed')) + return + try: + save_argv = sys.argv + sys.argv = self.sys_argv + self.run_cell(next_block) + self.post_cmd() + finally: + sys.argv = save_argv + + except: + if self.inside_ipython: + self.ip_showtb(filename=self.fname) + else: + if self.inside_ipython: + self.ip_ns.update(self.user_ns) + + if self.block_index == self.nblocks: + mq1 = self.marquee('END OF DEMO') + if mq1: + # avoid spurious print if empty marquees are used + print() + print(mq1) + print(self.marquee('Use <demo_name>.reset() if you want to rerun it.')) + self.finished = True + + # These methods are meant to be overridden by subclasses who may wish to + # customize the behavior of of their demos. + def marquee(self,txt='',width=78,mark='*'): + """Return the input string centered in a 'marquee'.""" + return marquee(txt,width,mark) + + def pre_cmd(self): + """Method called before executing each block.""" + pass + + def post_cmd(self): + """Method called after executing each block.""" + pass + + def highlight(self, block): + """Method called on each block to highlight it content""" + tokens = pygments.lex(block, self.python_lexer) + if self.format_rst: + from pygments.token import Token + toks = [] + for token in tokens: + if token[0] == Token.String.Doc and len(token[1]) > 6: + toks += pygments.lex(token[1][:3], self.python_lexer) + # parse doc string content by rst lexer + toks += pygments.lex(token[1][3:-3], self.rst_lexer) + toks += pygments.lex(token[1][-3:], self.python_lexer) + elif token[0] == Token.Comment.Single: + toks.append((Token.Comment.Single, token[1][0])) + # parse comment content by rst lexer + # remove the extra newline added by rst lexer + toks += list(pygments.lex(token[1][1:], self.rst_lexer))[:-1] + else: + toks.append(token) + tokens = toks + return pygments.format(tokens, self.formatter) + + +class IPythonDemo(Demo): + """Class for interactive demos with IPython's input processing applied. + + This subclasses Demo, but instead of executing each block by the Python + interpreter (via exec), it actually calls IPython on it, so that any input + filters which may be in place are applied to the input block. + + If you have an interactive environment which exposes special input + processing, you can use this class instead to write demo scripts which + operate exactly as if you had typed them interactively. The default Demo + class requires the input to be valid, pure Python code. + """ + + def run_cell(self,source): + """Execute a string with one or more lines of code""" + + self.shell.run_cell(source) + +class LineDemo(Demo): + """Demo where each line is executed as a separate block. + + The input script should be valid Python code. + + This class doesn't require any markup at all, and it's meant for simple + scripts (with no nesting or any kind of indentation) which consist of + multiple lines of input to be executed, one at a time, as if they had been + typed in the interactive prompt. + + Note: the input can not have *any* indentation, which means that only + single-lines of input are accepted, not even function definitions are + valid.""" + + def reload(self): + """Reload source from disk and initialize state.""" + # read data and parse into blocks + self.fload() + lines = self.fobj.readlines() + src_b = [l for l in lines if l.strip()] + nblocks = len(src_b) + self.src = ''.join(lines) + self._silent = [False]*nblocks + self._auto = [True]*nblocks + self.auto_all = True + self.nblocks = nblocks + self.src_blocks = src_b + + # also build syntax-highlighted source + self.src_blocks_colored = list(map(self.highlight,self.src_blocks)) + + # ensure clean namespace and seek offset + self.reset() + + +class IPythonLineDemo(IPythonDemo,LineDemo): + """Variant of the LineDemo class whose input is processed by IPython.""" + pass + + +class ClearMixin(object): + """Use this mixin to make Demo classes with less visual clutter. + + Demos using this mixin will clear the screen before every block and use + blank marquees. + + Note that in order for the methods defined here to actually override those + of the classes it's mixed with, it must go /first/ in the inheritance + tree. For example: + + class ClearIPDemo(ClearMixin,IPythonDemo): pass + + will provide an IPythonDemo class with the mixin's features. + """ + + def marquee(self,txt='',width=78,mark='*'): + """Blank marquee that returns '' no matter what the input.""" + return '' + + def pre_cmd(self): + """Method called before executing each block. + + This one simply clears the screen.""" + from IPython.utils.terminal import _term_clear + _term_clear() + +class ClearDemo(ClearMixin,Demo): + pass + + +class ClearIPDemo(ClearMixin,IPythonDemo): + pass + + +def slide(file_path, noclear=False, format_rst=True, formatter="terminal", + style="native", auto_all=False, delimiter='...'): + if noclear: + demo_class = Demo + else: + demo_class = ClearDemo + demo = demo_class(file_path, format_rst=format_rst, formatter=formatter, + style=style, auto_all=auto_all) + while not demo.finished: + demo() + try: + py3compat.input('\n' + delimiter) + except KeyboardInterrupt: + exit(1) + +if __name__ == '__main__': + import argparse + parser = argparse.ArgumentParser(description='Run python demos') + parser.add_argument('--noclear', '-C', action='store_true', + help='Do not clear terminal on each slide') + parser.add_argument('--rst', '-r', action='store_true', + help='Highlight comments and dostrings as rst') + parser.add_argument('--formatter', '-f', default='terminal', + help='pygments formatter name could be: terminal, ' + 'terminal256, terminal16m') + parser.add_argument('--style', '-s', default='default', + help='pygments style name') + parser.add_argument('--auto', '-a', action='store_true', + help='Run all blocks automatically without' + 'confirmation') + parser.add_argument('--delimiter', '-d', default='...', + help='slides delimiter added after each slide run') + parser.add_argument('file', nargs=1, + help='python demo file') + args = parser.parse_args() + slide(args.file[0], noclear=args.noclear, format_rst=args.rst, + formatter=args.formatter, style=args.style, auto_all=args.auto, + delimiter=args.delimiter) |