[PATCH 2 of 2] hghave: require clang-format >= 6 due to output change

[Yuya Nishihara]

# HG changeset patch
# User Yuya Nishihara <yuya at tcha.org>
# Date 1531533112 -32400
#      Sat Jul 14 10:51:52 2018 +0900
# Node ID d5b851a39710f8415f98575e4f00396fe7ee2809
# Parent  42bce1d7778658cae95ec0a2aa29ff72d503c000
hghave: require clang-format >= 6 due to output change

diff --git a/tests/hghave.py b/tests/hghave.py
--- a/tests/hghave.py
+++ b/tests/hghave.py
@@ -452,8 +452,9 @@ def has_pylint():
 
 @check("clang-format", "clang-format C code formatter")
 def has_clang_format():
-    return matchoutput("clang-format --help",
-                       br"^OVERVIEW: A tool to format C/C\+\+[^ ]+ code.")
+    m = matchoutput('clang-format --version', br'clang-format version (\d)')
+    # style changed somewhere between 4.x and 6.x
+    return m and int(m.group(1)) >= 6
 
 @check("jshint", "JSHint static code analysis tool")
 def has_jshint():