[issue11123] problem with packaged dependency extracter script, pdeps

[$$Coffeepot$$]

New submission from $$Coffeepot$$ <coffeepottttttttt at yahoo.com>:

This bug concerns the pdeps script, <python directory>\Tools\Scripts\pdeps.py. This script opens a list of files and extracts a list of their inter-dependencies.

I'm running Python 3.1.1 on Windows XP, installed via binary installer, but have confirmed that the bug is present in the source distribution of Python 3.2 rc2, the newest code I know of. (In fact, the only difference between the pdeps.py files in each version was the shebang line, 3.2 rc2 shebang line: "#! /usr/bin/env python3", 3.1.1 shebang line: "#! /usr/bin/env python".)

When I tried out the module I found a series of small bugs, basically typos, each of which caused the script to crash due to an unhandled exception.

1.

The relevant section of the unmodified pdeps.py file
----
# Compiled regular expressions to search for import statements
#
m_import = re.compile('^[ \t]*from[ \t]+([^ \t]+)[ \t]+')
m_from = re.compile('^[ \t]*import[ \t]+([^#]+)')


# Collect data from one file
#
def process(filename, table):
...
        if m_import.match(line) >= 0:
            (a, b), (a1, b1) = m_import.regs[:2]
        elif m_from.match(line) >= 0:
            (a, b), (a1, b1) = m_from.regs[:2]
...

The match method of a compiled regular expression returns an SREMatch object, so the conditionals must be changed. In addition, the regs data is a member of the match object itself, not the compiled expression object, so the right side of the assignments must also be changed.

modified version
----
...
        import_match = m_import.match(line)
        from_match = m_from.match(line)
        if import_match:
            (a, b), (a1, b1) = import_match.regs[:2]
        elif from_match:
            (a, b), (a1, b1) = from_match.regs[:2]
...

2.

unmodified
----
# Invert a table (this is again totally general).
# All keys of the original table are made keys of the inverse,
# so there may be empty lists in the inverse.
#
def inverse(table):
    inv = {}
    for key in table.keys():
        if not inv.has_key(key):
            inv[key] = []
        for item in table[key]:
            store(inv, item, key)
    return inv

Dictionaries have no has_key method, though I vaguely recall that they used to. That's a quick fix though.

modified
----
# Invert a table (this is again totally general).
# All keys of the original table are made keys of the inverse,
# so there may be empty lists in the inverse.
#
def inverse(table):
    inv = {}
    for key in table.keys():
        if key in inv:
            inv[key] = []
        for item in table[key]:
            store(inv, item, key)
    return inv

output of fc, windows file comparing utility, run on the pdeps file from 3.2 rc2, and the modified pdeps file from 3.1.1
----
>fc original-pdeps.py pdeps.py
Comparing files original-pdeps.py and PDEPS.PY
***** original-pdeps.py 
#! /usr/bin/env python3

***** PDEPS.PY
#! /usr/bin/env python

*****

***** original-pdeps.py 
            line = line[:-1] + nextline
        if m_import.match(line) >= 0:
            (a, b), (a1, b1) = m_import.regs[:2]
        elif m_from.match(line) >= 0:
            (a, b), (a1, b1) = m_from.regs[:2]
        else: continue
***** PDEPS.PY
            line = line[:-1] + nextline
        import_match = m_import.match(line)
        from_match = m_from.match(line)
        if import_match:
            (a, b), (a1, b1) = import_match.regs[:2]
        elif from_match:
            (a, b), (a1, b1) = from_match.regs[:2]
        else: continue
*****

***** original-pdeps.py 
    for key in table.keys():
        if not inv.has_key(key):
            inv[key] = []
***** PDEPS.PY
    for key in table.keys():
        if key in inv:
            inv[key] = []
*****

With these changes the pdep script works as expected.

This is a pretty lower priority bug imho. It prevents anyone from using the script, but fixing the bug took about 5 minutes, and I doubt the pdeps script gets much use anyway. This bug is unlikely to inconvenience anyone.

----------
components: Demos and Tools
messages: 127947
nosy: $$Coffeepot$$
priority: normal
severity: normal
status: open
title: problem with packaged dependency extracter script, pdeps
type: crash
versions: Python 3.1, Python 3.2

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Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue11123>
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