commands: fix completion descriptions

[ZhongRuoyu]

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The following tests failed but I don't think they are related. (On my Mac, they failed on master, too.)

Failures

(output truncated & reformatted)

Failures:


Cask::DSL language stanza when language is set explicitly to 'en' is expected to be the english version

Failure/Error: it { is_expected.to be_the_english_version }

./test/cask/dsl_spec.rb:214:in block (5 levels) in <top (required)>' ./test/support/helper/spec/shared_context/homebrew_cask.rb:52:in block (2 levels) in <top (required)>'


Cask::DSL language stanza when language is set explicitly to 'xx-XX' is expected to be the english version

Failure/Error: it { is_expected.to be_the_english_version }

./test/cask/dsl_spec.rb:220:in block (5 levels) in <top (required)>' ./test/support/helper/spec/shared_context/homebrew_cask.rb:52:in block (2 levels) in <top (required)>'


brew bottle builds a bottle for the given Formula

Failure/Error:

expect { brew "bottle", "--no-rebuild", "testball" }

.to output(/testball--0.1.*.bottle.tar.gz/).to_stdout

.and not_to_output.to_stderr

.and be_a_success

./test/dev-cmd/bottle_spec.rb:20:in block (2 levels) in <top (required)>' ./test/support/helper/spec/shared_context/integration_test.rb:50:in block (2 levels) in <top (required)>'

---

Currently, zsh and fish shell completions show incomplete descriptions
for certain commands. For example:

docs                         -- Open Homebrew's online documentation (https://docs
rbenv-sync                   -- Create symlinks for Homebrew's installed Ruby versions in ~/

This is because Commands.command_description produces incomplete
short descriptions for the commands having a dot (from a URL or a path)
in the first sentence; the dot is misinterpreted as a full stop:

brew(main):001:0> Commands.command_description("docs", short: true)
=> "Open Homebrew's online documentation (https://docs"
brew(main):002:0> Commands.command_description("rbenv-sync", short: true)
=> "Create symlinks for Homebrew's installed Ruby versions in ~/" 

We can improve the sentence splitting logic by only splitting at dots
either at the end or followed by a whitespace. Now With this change:

brew(main):001:0> Commands.command_description("docs", short: true)
=> "Open Homebrew's online documentation (https://docs.brew.sh) in a browser"
brew(main):002:0> Commands.command_description("rbenv-sync", short: true)
=> "Create symlinks for Homebrew's installed Ruby versions in ~/.rbenv/versions"

[carlocab]

Nice catch.

[MikeMcQuaid]

@ZhongRuoyu Could this get a Ruby comment added above clarifying what this is doing and why? It's not obvious from reading the code alone. Thanks!