Add ClangFormat and pre-commit support files (#854)

* add '.clang-format', '.pre-commit-config.yaml' and '.git-blame-ignore-revs* files
* CI: add ClangFormat Check

.clang-format

@@ -0,0 +1,30 @@
+---
+BasedOnStyle: LLVM
+IndentWidth: 4
+---
+Language: Cpp
+AccessModifierOffset: -4
+AlignConsecutiveMacros:
+  Enabled: true
+  AcrossEmptyLines: true
+  AcrossComments: true
+  PadOperators: true
+AlignEscapedNewlines: Left
+AllowShortFunctionsOnASingleLine: InlineOnly
+AlwaysBreakTemplateDeclarations: Yes
+BreakBeforeBraces: Stroustrup
+ForEachMacros:
+  - DGL_FOREACH_NODE
+  - DGL_FOREACH_EDGE
+  - BOOST_FOREACH
+IfMacros:
+  - SORT_DEBUG
+MacroBlockBegin: GNO_BEGIN
+MacroBlockEnd: GNO_END
+SortIncludes: Never
+---
+Language: ObjC
+---
+Language: JavaScript
+---
+Language: Json

.git-blame-ignore-revs

@@ -0,0 +1,2 @@
+5fb6b1a969e72db28df78483d3360b15a17f0c68
+cac8d9d848299297977d1315b7e90cc3f7698730

.github/workflows/clang-format-check.yml

@@ -0,0 +1,19 @@
+---
+name: ClangFormat Check
+
+on:
+  push:
+    branches:
+      - grass*
+  pull_request:
+jobs:
+  formatting-check:
+    name: Formatting Check
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Run clang-format style check for C/C++/Protobuf programs.
+        uses: jidicula/clang-format-action@v4.10.1
+        with:
+          clang-format-version: '15'
+          check-path: .

.pre-commit-config.yaml

@@ -0,0 +1,42 @@
+---
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.4.0
+    hooks:
+      - id: trailing-whitespace
+        exclude: |
+          (?x)^(
+                .*\.ascii$|
+                .*\.ref$|
+                .*\.diff$|
+                .*\.rtf$|
+                .*\.kate-swp$|
+                .*\.svg$
+          )
+      - id: end-of-file-fixer
+        exclude: |
+          (?x)^(
+                .*\.ascii$|
+                .*\.ref$|
+                .*\.diff$|
+                .*\.rtf$|
+                .*\.kate-swp$|
+                .*\.svg$
+          )
+  - repo: https://github.com/igorshubovych/markdownlint-cli
+    rev: v0.33.0
+    hooks:
+      - id: markdownlint
+  - repo: https://github.com/psf/black
+    rev: 22.3.0
+    hooks:
+      - id: black
+  - repo: https://github.com/pycqa/flake8
+    rev: 3.9.2
+    hooks:
+      - id: flake8
+  - repo: https://github.com/pre-commit/mirrors-clang-format
+    rev: v15.0.6
+    hooks:
+      - id: clang-format
+        types_or: [c, c++, javascript, json, objective-c]