Switch from astyle to clang-format for automated code formatting

I added a `.clang-format` file to try to get as close as possible to our current
code formatting.  I also updated the makefile targets and the github workflows.

Signed-off-by: Michael Richters <gedankenexperimenter@gmail.com>

.clang-format

@@ -0,0 +1,47 @@
+# -*- mode: yaml -*-
+---
+BasedOnStyle: Google
+---
+Language: Cpp
+
+AlignConsecutiveAssignments: Consecutive
+## clang-format-15
+# AlignConsecutiveAssignments:
+#   Enabled: true
+#   AlignCompound: true
+#   PadOperators: true
+AlignConsecutiveDeclarations: None
+AlignConsecutiveMacros: AcrossEmptyLines
+AlignEscapedNewlines: Right
+AllowShortBlocksOnASingleLine: Empty
+AllowShortIfStatementsOnASingleLine: WithoutElse
+AllowShortFunctionsOnASingleLine: Inline
+AllowShortLoopsOnASingleLine: true
+AttributeMacros:
+  - __attribute__((weak))
+  - __attribute__((always_inline))
+  - __attribute__((noinline))
+  - __attribute__((packed))
+  - __attribute__((optimize(3)))
+  - __attribute__((unused))
+BinPackArguments: false
+BinPackParameters: false
+# BraceWrapping:
+#   SplitEmptyFunction: false
+#   SplitEmptyRecord: true
+#   SplitEmptyNamespace: true
+# BreakBeforeBraces: Custom
+ColumnLimit: 0
+ConstructorInitializerIndentWidth: 2
+ContinuationIndentWidth: 2
+DerivePointerAlignment: false
+FixNamespaceComments: true
+IndentCaseLabels: false
+KeepEmptyLinesAtTheStartOfBlocks: true
+MaxEmptyLinesToKeep: 2
+# PackConstructorInitializers: CurrentLine
+PointerAlignment: Right
+# ReferenceAlignment: Right
+ReflowComments: false
+SortIncludes: false
+SpaceAfterTemplateKeyword: false

.github/workflows/build.yml

@@ -6,6 +6,7 @@ env:
   LC_ALL: C
   KALEIDOSCOPE_CCACHE: 1
   ARDUINO_DIRECTORIES_USER: ${{ github.workspace }}/.arduino/user
+  CLANG_FORMAT_CMD: clang-format-12
 jobs:
   smoke-sketches:
     runs-on: ubuntu-latest
@@ -25,12 +26,11 @@ jobs:
     - run: sudo apt-get install ccache
     - run: make setup
     - run: make -j $(nproc) simulator-tests
-  check-astyle:
+  check-formatting:
     runs-on: ubuntu-latest
     steps:
-    - run: sudo apt-get install astyle
     - uses: actions/checkout@v2
-    - run: make check-astyle
+    - run: make check-formatting
   check-shellcheck:
     runs-on: ubuntu-latest
     steps:

Makefile

@@ -88,17 +88,13 @@ adjust-git-timestamps:
 find-filename-conflicts:
 	bin/find-filename-conflicts
 
-.PHONY: astyle test cpplint cpplint-noisy shellcheck smoke-examples find-filename-conflicts prepare-virtual checkout-platform adjust-git-timestamps docker-bash docker-simulator-tests run-tests simulator-tests setup
+.PHONY: format check-formatting cpplint cpplint-noisy shellcheck smoke-examples find-filename-conflicts prepare-virtual checkout-platform adjust-git-timestamps docker-bash docker-simulator-tests run-tests simulator-tests setup
 
-astyle:
+format:
-	find ./* -type f \( -name  '*.h' -o -name '*.cpp' -o -name '*.ino' \) | grep -v "testing/googletest" | xargs -n 1 astyle --project
+	bin/format-code.sh
 
-check-astyle: astyle
+check-formatting:
-	if ! git diff --exit-code; then \
+	bin/format-code.sh --check
-  	 >&2 echo "'astyle' found code style differences. Please make astyle and commit your changes"; \
-	 exit 1; \
-	fi; \
-	exit 0;
 
 cpplint-noisy:
 	-bin/cpplint.py  --filter=-legal/copyright,-build/include,-readability/namespace,-whitespace/line_length,-runtime/references  --recursive --extensions=cpp,h,ino src examples

bin/format-code.sh

@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+# Allow the caller to specify a particular version of clang-format to use:
+: "${CLANG_FORMAT_CMD:=clang-format}"
+
+# Find all *.cpp and *.h files, except those in `testing/googletest/` and files
+# generated by testcase scripts, and run `clang-format` on them:
+find ./* -type f \( -name '*.h' -o -name '*.cpp' \) \
+     -not \( -path './testing/googletest/*' -o -name 'generated-testcase.cpp' \) \
+     -print0 | \
+    xargs -0 "${CLANG_FORMAT_CMD}" -i
+
+# If we get the `--check` option, return an error if there are any changes to
+# the git working tree after running `clang-format`:
+if [[ $1 == '--check' ]]; then
+
+    if ! git diff --quiet; then
+        cat >&2 <<EOF
+Differences found between git head and working tree.  Either 'clang-format' made
+formatting changes to your code, or you had uncommitted changes in your working
+tree.  Please remember to run 'bin/format-code.sh' before committing changes.
+EOF
+        exit 1
+    fi
+fi