An issue could arise when brewing a formula that
has Python 2.x and 3.x support and 2.x is the system Python
but 3.x is a brewed one. The idea about prepending was that
user configured PYTHONPATH could be used in formulae.
Now, instead and if needed, inside the `python do` block
one can still append to PYTHONPATH.
If `depends_on :python => ['modulename', :optional]` then the generated
option is now `--with-python-modulename`, so that it is possible to
actually make depending on python modules optional.
Further, `brew options` becomes more meaningful.
When a formula `depends_on :python` *and* `depends_on :python3`
the `modify_build_environment` method sets the PYTHONPATH
and the Python 3.x requirement then fails because it finds
the sitecustomize.py from Python 2.x in the PYTHONPATH.
Options collections are backed by Sets, and thus trying to push a new
option with a name that duplicates an existing option cannot succeed.
Later, we can exploit this behavior and remove some conditionals.
... and not just installed ones. Of course, strictly speaking,
reinstalling not-yet-installed formulae makes semantically little
sense, but the big win is that we can tell people (after we have
resolved an issue) to `brew reinstall <formula>` and even if a user
has removed that formula in the meantime, reinstall will do the right
thing. Basically adding --force to uninstall. I think this makes
reinstall more robust.
... and not just installed ones. Of course, strictly speaking,
reinstalling not-yet-installed formulae makes semantically little
sense, but the big win is that we can tell people (after we have
resolved an issue) to `brew reinstall <formula>` and even if a user
has removed that formula in the meantime, reinstall will do the right
thing. Basically adding --force to uninstall. I think this makes
reinstall more robust.
On Unix, the path separator is ':', whereas on Windows,
it is ';'. This is the first of a series of patch to bring
macbrew's and winbrew's codebases closer together.
The main places the magic constant ':' was being used were:
- the $PATH environment variable
- CMAKE-related environment variables
- pkg-config related environment variables
ClosesHomebrew/homebrew#21921.
Signed-off-by: Jack Nagel <jacknagel@gmail.com>
We override ENV[] to always return strings under superenv, because
legacy formulae assume that CFLAGS, etc. are non-nil.
However, the current implementation has a bug. If I simply concatenate
ENV['CFLAGS'] with another string, it mutates ENV['CFLAGS']:
irb> ENV['CFLAGS']
=> ""
irb> ENV['CFLAGS'] + 'a'
=> "a"
irb> ENV['CFLAGS']
=> "a"
Instead, let's simply return an empty string if the key doesn't exist.
This is sufficient because the following are equivalent:
1. ENV['CFLAGS'] += "string"
2. ENV['CFLAGS'] = ENV['CFLAGS'] + "string"
