Merge pull request #224 from thewtex/clang-format-hook

ENH: Add clang-format pre-commit hook

Author: thewtex

.gitattributes

@@ -1,5 +1,5 @@
 # Custom attribute to mark sources as using our C++/C code style.
-[attr]our-c-style  whitespace=tab-in-indent,no-lf-at-eof  hooks.style=KWStyle,clangformat
+[attr]our-c-style  whitespace=tab-in-indent,no-lf-at-eof  hooks.style=clangformat
 
 *.c              our-c-style
 *.h              our-c-style

Superbuild/External-ClangFormat.cmake

@@ -0,0 +1,43 @@
+include(ExternalProject)
+
+if(WIN32)
+  set(exe .exe)
+endif()
+set(CLANG_FORMAT_EXECUTABLE ${CMAKE_CURRENT_BINARY_DIR}/ClangFormat-prefix/src/ClangFormat/clang-format${exe})
+configure_file("${CMAKE_CURRENT_SOURCE_DIR}/ITKClangFormatConfig.cmake.in"
+               "${CMAKE_CURRENT_BINARY_DIR}/ITKClangFormatConfig.cmake" @ONLY)
+
+set(_clang_format_hash )
+set(_clang_format_url )
+if(CMAKE_HOST_SYSTEM_NAME MATCHES "Linux" AND CMAKE_HOST_SYSTEM_PROCESSOR STREQUAL "x86_64")
+  set(_clang_format_hash
+    b14de32036c48f6c62998e2ebab509e71a0ae71464acb4616484e3a6eb941e1d9fac38559f5d27ea0cbbb512d590279ffb3015fae17779229e1090c2763ebcf3)
+  set(_clang_format_url "https://data.kitware.com/api/v1/file/hashsum/sha512/${_clang_format_hash}/download")
+elseif(CMAKE_HOST_SYSTEM_NAME MATCHES "Darwin" AND CMAKE_HOST_SYSTEM_PROCESSOR STREQUAL "x86_64" AND (NOT CMAKE_HOST_SYSTEM_VERSION VERSION_LESS "13.0.0"))
+  set(_clang_format_hash
+    97460f9eef556a27592ccd99d8fc894554e5b3196326df4e33bfcdecfcb7eda2b5c7488008abc4dd923d607f2cb47d61567b1da99df60f31f719195118c117a9)
+  set(_clang_format_url "https://data.kitware.com/api/v1/file/hashsum/sha512/${_clang_format_hash}/download")
+elseif(CMAKE_HOST_SYSTEM_NAME MATCHES "Windows" AND CMAKE_HOST_SYSTEM_PROCESSOR STREQUAL "AMD64")
+  set(_clang_format_hash
+    e96dd15938fd9b1c57028a519189f138397774eb6b66971d114300d2a80248adda9f74b192985a3c91c7de52c4dbe21800bc6b3cc8201c4985fc39ecfc64fdbe)
+  set(_clang_format_url "https://data.kitware.com/api/v1/file/hashsum/sha512/${_clang_format_hash}/download")
+else()
+  # If desired, a compatible clang-format can be provided manually with
+  #   `git config clangFormat.binary /path/to/clang-format`.
+endif()
+
+if(NOT TARGET ClangFormat AND _clang_format_hash)
+  ExternalProject_add(ClangFormat
+    URL ${_clang_format_url}
+    URL_HASH SHA512=${_clang_format_hash}
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND ""
+    LOG_DOWNLOAD 1
+    LOG_UPDATE 0
+    LOG_CONFIGURE 0
+    LOG_BUILD 0
+    LOG_TEST 0
+    LOG_INSTALL 0
+    INSTALL_COMMAND ${CMAKE_COMMAND} -P ${CMAKE_CURRENT_BINARY_DIR}/ITKClangFormatConfig.cmake
+    )
+endif()

Superbuild/ITKClangFormatConfig.cmake.in

@@ -0,0 +1,17 @@
+set(ITKExamples_SOURCE_DIR "@ITKExamples_SOURCE_DIR@")
+set(CMAKE_SOURCE_DIR "@CMAKE_SOURCE_DIR@")
+set(CLANG_FORMAT_EXECUTABLE "@CLANG_FORMAT_EXECUTABLE@")
+
+set(WORKING_DIR "")
+if(ITKExamples_SOURCE_DIR)
+  set(WORKING_DIR "${ITKExamples_SOURCE_DIR}/..")
+else()
+  set(WORKING_DIR "${CMAKE_SOURCE_DIR}/..")
+endif()
+
+find_package(Git)
+if(GIT_FOUND AND EXISTS "${WORKING_DIR}/.git/config")
+  execute_process(COMMAND ${GIT_EXECUTABLE} config clangFormat.binary
+    "${CLANG_FORMAT_EXECUTABLE}"
+    WORKING_DIRECTORY ${WORKING_DIR})
+endif()

Superbuild/Superbuild.cmake

@@ -119,3 +119,19 @@ ExternalProject_Add(ITKExamples
     -DExternalData_OBJECT_STORES:STRING=${ExternalData_OBJECT_STORES}
   INSTALL_COMMAND ""
 )
+
+# Download and configure clang-format for style uniformity during development.
+#
+# This code helps download a version of clang-format binaries consistent with
+# ITK's clang-format configuration. Git configuration is added during
+# development to help automatically apply the formatting.
+#
+# Globally, the ITK/.clang-format file provides the base style configuration.
+# For more information on ITK coding style, see the ITK Coding Style Guide in
+# the ITK Software Guide.
+option(ITKExamples_USE_CLANG_FORMAT "Enable the use of clang-format for coding style formatting." ${BUILD_TESTING})
+mark_as_advanced(ITKExamples_USE_CLANG_FORMAT)
+
+if(BUILD_TESTING AND ITKExamples_USE_CLANG_FORMAT AND NOT CMAKE_CROSSCOMPILING)
+  include(${CMAKE_SOURCE_DIR}/External-ClangFormat.cmake)
+endif()

Utilities/Hooks/pre-commit

@@ -42,3 +42,7 @@ if test $lastSetupForDevelopment -lt $SetupForDevelopment_VERSION; then
   \"$top_level_dir/Utilities/SetupForDevelopment.sh\"
 "
 fi
+
+#-----------------------------------------------------------------------------
+# Style hooks.
+. "${BASH_SOURCE%/*}/pre-commit-style.bash"