Building NSIS from source on windows (VS2012) - nsis

Question

I'm working on a pure x64 version of my software. Our installer for the x86 version is NSIS and my software is built using VS2012. I found online that in order to build x64 installers using NSIS you have to build NSIS (and all plugins/etc) from source. That is the end goal. However, right now I'm having issues just building x86 (before moving on to x64) using the instructions in the NSIS docs. https://nsis.sourceforge.io/Docs/AppendixG.html#build_windows
I'm trying to build NSIS v3.0.4 which uses SCons to build. I've installed scons using pip (SCons version 3.1.1).
However, when trying to build NSIS, I get the following (using python 3.8.0).
C:\Source\nsis\nsis-code-r7069-NSIS-tags-v304>scons ZLIB_W32=C:\Source\zlib-1.2.7 MSTOOLKIT=yes
scons: Reading SConscript files ...
TypeError: cannot use a string pattern on a bytes-like object:
File "C:\Source\nsis\nsis-code-r7069-NSIS-tags-v304\SConstruct", line 263:
for v in re.compile(r'^\\H\{[v]?(\S+)\}', re.M).finditer(File('#/Docs/src/history.but').get_contents()): # Try to parse the Halibut history file
the section of the SConstruct file is as follows (starting at line 260 so the for loop starts at 263):
if not defenv.has_key('VER_PACKED'):
import re
found = None
for v in re.compile(r'^\\H\{[v]?(\S+)\}', re.M).finditer(File('#/Docs/src/history.but').get_contents()): # Try to parse the Halibut history file
if v and not found:
v = v.group(1).split('.')
if len(v) >= 2:
mi = int(re.search(r'\d+', v[1]).group())
if mi < 1: mi = 1 # Make sure we can subtract 1 from the minor number so trunk stays below the next release
defenv['VER_PACKED'] = '0x%0.2i%0.3i%0.2i%0.1i' % (int(re.search(r'\d+', v[0]).group()), mi - 1, 66, 6)
if int(defenv['VER_PACKED'], 0) >= int('0x03000000', 0):
found = v
if not found:
defenv['VER_PACKED'] = '0x%0.2i%0.3i%0.2i%0.1i' % (3, 3, 42, 0) # Default to a version number we never used
print('WARNING: VER_PACKED not set, defaulting to %s!' % defenv['VER_PACKED'])
At this point, I'm not sure if there is a dependency I'm missing or if this is an issue with the build script and needs to be reported at the NSIS issue tracker. Ideas?
-UPDATE 1-
Based on suggestions from #Anders, first I tried to build the head of the repo (r7132 trunk) instead of v3.0.4 using Python3. This got me farther but still failed on what appears to be Python2 vs 3 syntax errors in mstoolkit.py (might be a symptom of another issue rather than the cause though). I didn't investigate this too much further yet.
So next, I went back to Python 2.7. This got me further but the mstoolkit.py appears to be dependent on VS2003 implementation. I duplicated the VCToolkitInstallDir environment variable on my machine using the contents of the VS110COMNTOOLS (C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\Tools) but that fails also:
File "C:\Source\IQClient_Interim\Shared\third_party\nsis\nsis-code-r7132-NSIS-tags-v304\SCons\Tools\mstoolkit.py", line 87, in get_msvctoolkit_paths
raise SCons.Errors.InternalError, "The Platform SDK directory was not found in the registry or in the `MSSdk` environment variable."
InternalError: The Platform SDK directory was not found in the registry or in the `MSSdk` environment variable.
I don't know what the VS2003 VCToolkitInstallDir ENVVAR was pointing to to fix this.
With all that said, I just noticed that Anders said that I might also have to use an older version of scons as well with python2.7 so I suppose I'll spend some time investigating that (along with looking into #bdbaddog's solution).
-UPDATE 2-
it was the mstoolkit directive (see #Anders answer's comments)
I got it working after that while using py 2.7 for NSIS 3.0.4.
Now on to x64 build but that's a different story so I'll post a different question.

Answer 1

NSIS v3.04 does not support Python 3, you have to grab the latest source code from SVN. v3.05 is coming out soon with support for Python 3.
VS2012 is old enough that you should be able to use Python 2.7 and a older version of SCons as an alternative.
As a final alternative, you can try to apply this diff to v3.04.

Answer 2

The issue you're running into is twofold.
Python > 3.0 strings are no longer bytes. They are unicode
SCons which supports Python > 3.0 (SCons >3.0 supports Python 2.7 and Python > 3.5.0)
In order to support this Node()'s (SCons's way of representing files, directories, and values which feed into a build) now have two methods get_contents() and get_text_contents().
Since you're using Python 3.8.0, get_contents() will return bytes, which explains the error you've received.
The proper way to resolve it is to change this line:
for v in re.compile(r'^\\H\{[v]?(\S+)\}', re.M).finditer(File('#/Docs/src/history.but').get_contents()): # Try to parse the Halibut history file
to:
for v in re.compile(r'^\\H\{[v]?(\S+)\}', re.M).finditer(File('#/Docs/src/history.but').get_text_contents()): # Try to parse the Halibut history file
Please let me know if this doesn't resolve the issue.
Also, if you're willing to install Python 2.7 and reinstall SCons via
py -2.7 -mpip install scons
(Assuming you've install the py launcher when installing Python. Not sure if that's default with Python 3.8 and/or Python 2.7. If not then /python -m pip install scons. You might have to install pip as well. Once again not sure on the default for that.)
Then you can avoid changing the SConstruct file.
Hope this helps!