gnulib-tool.py: Fix pylint 'attribute-defined-outside-init' warnings.

[Collin Funk]

I mentioned a change involving moving an attribute definition to its
proper place in __init__ here:

    https://lists.gnu.org/archive/html/bug-gnulib/2024-04/msg00270.html

But I noticed that pylint will warn about these [1]. So it seems
easier to fix them all at once instead of in the middle of other
changes.

$ pylint *.py | grep W0201
GLError.py:119:12: W0201: Attribute 'message' defined outside __init__ 
(attribute-defined-outside-init)
GLImport.py:1043:8: W0201: Attribute 'assistant' defined outside __init__ 
(attribute-defined-outside-init)
GLModuleSystem.py:916:8: W0201: Attribute 'modules' defined outside __init__ 
(attribute-defined-outside-init)

GLError seems like it was never completed, since we have the error
messages repeated under "if __name__ == '__main__':". But it seems
__repr__ expects 'messages' to be initialized to None. So we can just
do that now in __init__.

GLImport defines 'assistant' in GLImport.execute(). I plan to remove
that definition and just mutate an instance attribute. Before that
change, it is harmless to initialize it to a GLFileAssistant in
__init__ so lets do that. We already unnecessarily create a
GLFileSystem that we don't need to [2] [3]. :)

The GLModuleSystem.transitive_closure() function defines a 'modules'
attribute that is never used. We can just remove it.

[1] 
https://pylint.readthedocs.io/en/latest/user_guide/messages/warning/attribute-defined-outside-init.html
[2] 
https://git.savannah.gnu.org/cgit/gnulib.git/tree/pygnulib/GLImport.py?id=64a7072ee8636c53bc2000505668bd0e33bb427e#n305
[3] 
https://git.savannah.gnu.org/cgit/gnulib.git/tree/pygnulib/GLImport.py?id=64a7072ee8636c53bc2000505668bd0e33bb427e#n1134

Collin
From 583b0470f53a3ed707c3a809ac209747780fa490 Mon Sep 17 00:00:00 2001
From: Collin Funk <collin.fu...@gmail.com>
Date: Tue, 16 Apr 2024 20:21:04 -0700
Subject: [PATCH] gnulib-tool.py: Fix pylint 'attribute-defined-outside-init'
 warnings.

* pygnulib/GLError.py (GLError.__init__): Define the 'messages'
attribute to None.
* pygnulib/GLImport.py (GLImport.__init__): Define the 'assistant'
attribute to a GLFileAssistant object.
* pygnulib/GLModuleSystem.py (GLModuleTable.transitive_closure): Don't
define a 'modules' attribute since it is never used.
---
 ChangeLog                  | 10 ++++++++++
 pygnulib/GLError.py        |  1 +
 pygnulib/GLImport.py       |  1 +
 pygnulib/GLModuleSystem.py |  1 -
 4 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index ffe35d5d1d..863a750109 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+2024-04-16  Collin Funk  <collin.fu...@gmail.com>
+
+	gnulib-tool.py: Fix pylint 'attribute-defined-outside-init' warnings.
+	* pygnulib/GLError.py (GLError.__init__): Define the 'messages'
+	attribute to None.
+	* pygnulib/GLImport.py (GLImport.__init__): Define the 'assistant'
+	attribute to a GLFileAssistant object.
+	* pygnulib/GLModuleSystem.py (GLModuleTable.transitive_closure): Don't
+	define a 'modules' attribute since it is never used.
+
 2024-04-16  Sam James  <s...@gentoo.org>
 
 	wchar: Fix serial number.
diff --git a/pygnulib/GLError.py b/pygnulib/GLError.py
index a990c382b1..fd7cb96975 100644
--- a/pygnulib/GLError.py
+++ b/pygnulib/GLError.py
@@ -68,6 +68,7 @@ def __init__(self, errno: int, errinfo: str | float | None = None) -> None:
         self.errno = errno
         self.errinfo = errinfo
         self.args = (self.errno, self.errinfo)
+        self.message = None
 
     def __repr__(self) -> str:
         errno = self.errno
diff --git a/pygnulib/GLImport.py b/pygnulib/GLImport.py
index c6a4693c90..a68399f561 100644
--- a/pygnulib/GLImport.py
+++ b/pygnulib/GLImport.py
@@ -304,6 +304,7 @@ def __init__(self, config: GLConfig, mode: int) -> None:
         self.emitter = GLEmiter(self.config)
         self.filesystem = GLFileSystem(self.config)
         self.modulesystem = GLModuleSystem(self.config)
+        self.assistant = GLFileAssistant(self.config)
         self.moduletable = GLModuleTable(self.config,
                                          self.config.checkInclTestCategory(TESTS['all-tests']),
                                          self.config.checkInclTestCategory(TESTS['all-tests']))
diff --git a/pygnulib/GLModuleSystem.py b/pygnulib/GLModuleSystem.py
index 6aed38b9eb..40ac591dc4 100644
--- a/pygnulib/GLModuleSystem.py
+++ b/pygnulib/GLModuleSystem.py
@@ -913,7 +913,6 @@ def transitive_closure(self, modules: list[GLModule]) -> list[GLModule]:
             inmodules = sorted(set(inmodules))
             inc_all_tests = self.inc_all_indirect_tests
         modules = sorted(set(outmodules))
-        self.modules = modules
         return modules
 
     def transitive_closure_separately(self, basemodules: list[GLModule],
-- 
2.44.0