Also remove related helper method `Homebrew.help_s`.

If user inputs argument such as `-with-flag`, we can assume it's a bad flag.

Closes Homebrew/homebrew#49256

Closes Homebrew/homebrew#49550.

Signed-off-by: Xu Cheng <xucheng@me.com>

Homebrew developers have the corresponding variable permanently set in
their environment and wanting to appear like a Homebrew developer for a
single invocation is exceedingly rare. Additionally, the option won't be
recognized by `bin/brew`. (It is also undocumented.)

Using `HOMEBREW_DEVELOPER=1 brew <command>` is still possible, and not
more inconvenient than passing the `--homebrew-developer` option.

Closes Homebrew/homebrew#48322.

Signed-off-by: Martin Afanasjew <martin@afanasjew.de>

Add these new errors, and guards in formula installation and
cmd/{,un,re}install to match, move can_build? to the MacOS module,
flatten conditions, remove redundant can_build? check

reinstate removed (doctor) check

Everything that used HOMEBREW_CELLAR/canonical_name
could point to something that doesn't exist because
loader_for tries to load new name formula if no old
name found. However there can be software installed
from path with the same name that renamed formulae
had and we still need to link/unlink/uninstall etc
that software. The solution is Formulary#to_rack
method that returns rack for given name.
- Add Formulary#to_rack
- Update ARGV.kegs
- Update cmd/switch

Closes Homebrew/homebrew#42537.

Signed-off-by: Xu Cheng <xucheng@me.com>

Fixes Homebrew/homebrew#42470.

Closes Homebrew/homebrew#42354.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

Closes Homebrew/homebrew#38361.

Signed-off-by: Xu Cheng <xucheng@me.com>

People want to install things like GIMP using Homebrew so let's make it
easier for them to find a decent installation method.

Closes Homebrew/homebrew#34496.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>

It might be best not to use the word "lame" here, as it's often considered to be an ableist slur.

Closes Homebrew/homebrew#30915.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

This is experimental and will be reverted if it causes problems.

Closes Homebrew/homebrew#30392.

name is the user-provided string and may be an alias, path, or URL.

rack cannot be nil at the point where FormulaUnavailableError is raised,
so we don't need a branch to deal with that.

dirs will be empty if the rack directory does not exist.

These have all been moved to Formulary.

This fixes external commands that provide their own
help and version subcommands.

Closes Homebrew/homebrew#26755.

Symlinks in opt and LinkedKegs point directly at a keg in the cellar, so
only resolving one symlink should suffice, and make it clear what path
we are actually interested in.