Doctor false alarm re outdated CLT after PR #4936

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[x] ran brew update and can still reproduce the problem?
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The recent commit updating the expected Xcode stuff is broken (the commit that merged PR #4936). I'm on 10.13.6 and I have the 10.13 CLT for Xcode 10 (and also Xcode 10 itself), but doctor says:

Warning: A newer Command Line Tools release is available.
Update them from Software Update in the App Store.

(Also, it appears to have an extra newline after it, i.e., three instead of two.)

I bisected, so that commit is indeed the one.

Config:

HOMEBREW_VERSION: 1.7.6-38-gb41d2e5
ORIGIN: https://github.com/Homebrew/brew
HEAD: b41d2e52543a0b27babd2be3c90b08fc57f9aa32
Last commit: 3 hours ago
Core tap ORIGIN: https://github.com/Homebrew/homebrew-core
Core tap HEAD: 0e77738e8268abfdf53a21a0bef5c8e4f9bb4421
Core tap last commit: 3 hours ago
HOMEBREW_PREFIX: /usr/local
HOMEBREW_REPOSITORY: /usr/local/hb
HOMEBREW_CACHE: /stuff/brache
HOMEBREW_TEMP: /Users/chdiza/.tmp/tmpdir
HOMEBREW_BUILD_FROM_SOURCE: 1
HOMEBREW_DEV_CMD_RUN: 1
HOMEBREW_LOGS: /Users/chdiza/Library/Homebrew
HOMEBREW_NO_ANALYTICS: 1
HOMEBREW_NO_AUTO_UPDATE: 1
HOMEBREW_NO_EMOJI: 1
HOMEBREW_NO_GITHUB_API: 1
HOMEBREW_VERBOSE: 1
CPU: quad-core 64-bit ivybridge
Homebrew Ruby: 2.3.7 => /System/Library/Frameworks/Ruby.framework/Versions/2.3/usr/bin/ruby
Clang: 10.0 build 1000
Git: 2.19.0 => /usr/local/bin/git
Curl: 7.54.0 => /usr/bin/curl
macOS: 10.13.6-x86_64
CLT: 10.0.0.0.1.1535735448
Xcode: 10.0

Doctor: consists of just the erroneous warning of outdatedness, if I first unset HOMEBREW_BUILD_FROM_SOURCE.

Homebrew / brew

Doctor false alarm re outdated CLT after PR #4936 #5006