Merge branch 'bottle_hooks'

add testball_bottle formula for upcoming bottle unit testing, as well
as bottles directory containing test bottle (and symlinks)

add guard in Formula#file_modified? to prevent git popup

add guard in Superenv.bin before calling MacOS::Xcode.version

add guard against missing Xcode/CLT in Xcode.uncached_version

return nil instread of 0 in uncached_version when Xcode/CLT are not present, to distinguish from linuxbrew behavior

checks against pour_bottle? and needs_relocation?, add guard around keg.relocate_install_names to check pour_bottle?/needs_relocation? as well

needs_relocation? becomes skip_relocation?, use cellar attr to indicate relocation instead of does_not_need_relocation

MacOS.can_build? becomes MacOS.has_apple_developer_tools?

remove unneeded definition

change variable in FormulaInstaller.check_build_flags from bf to build_flags

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

This is so so that check_dependencies_bottled can be called when bottles
are being poured; implement check_dependencies_bottled

This becomes MacOS.{install_name_tool,otool}, only do check_xcode if
xcode is installed, otherwise emit a warning

Check @@attempted for cctools so that we only attempt the relocation
install once, skip cxxstdlib check in cctools to prevent otool
execution prior to installation, skip fixing install names if
relocation is not required

Install it as a dependency unless already satisfied by Xcode.

require cctools_requirement

cctools_requirement should be satisfied by cctools present in opt

add build_env => false to the satify block options in CctoolsRequirement

Until it can be adapted to not call otool on systems w/o XCode/CLT

Toggled with does_not_need_relocation method in bottle block.
Also declare needs_relocation? accessors in software/bottle specs.

Closes Homebrew/homebrew#43146.

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

Closes Homebrew/homebrew#43145.

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

Closes Homebrew/homebrew#42801.

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

Closes Homebrew/homebrew#43107.

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

Closes Homebrew/homebrew#43025.

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

Fixes Homebrew/homebrew#43002

Closes Homebrew/homebrew#43058.

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

Also reduce unnecessary disk operations

Closes Homebrew/homebrew#43024.

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

It can be useful when implementing custom https mirror strategy such as Homebrew/homebrew#42955.

Closes Homebrew/homebrew#43020.

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

These are minor perf optimizations.

Closes Homebrew/homebrew#43028.

Signed-off-by: Baptiste Fontaine <batifon@yahoo.fr>

Mixing 'brew remove' with 'brew uninstall' can confuse users.

Closes Homebrew/homebrew#43026.

Signed-off-by: Baptiste Fontaine <batifon@yahoo.fr>