Auto Formatting with clang-format-6.0 (#727)

* Add clang-format

* Auto-format AlphaFilter and RingBuffer

* Update to tab=8spaces

* Allow for 120 width

.clang-format

@@ -0,0 +1,117 @@
+---
+Language:        Cpp
+# BasedOnStyle:  Google
+AccessModifierOffset: -8 # Modified
+AlignAfterOpenBracket: Align
+AlignConsecutiveAssignments: false
+AlignConsecutiveDeclarations: false
+AlignEscapedNewlines: Left
+AlignOperands:   true
+AlignTrailingComments: true
+AllowAllParametersOfDeclarationOnNextLine: true
+AllowShortBlocksOnASingleLine: false
+AllowShortCaseLabelsOnASingleLine: false
+AllowShortFunctionsOnASingleLine: All
+AllowShortIfStatementsOnASingleLine: true
+AllowShortLoopsOnASingleLine: true
+AlwaysBreakAfterDefinitionReturnType: None
+AlwaysBreakAfterReturnType: None
+AlwaysBreakBeforeMultilineStrings: true
+AlwaysBreakTemplateDeclarations: true
+BinPackArguments: true
+BinPackParameters: true
+BraceWrapping:
+  AfterClass:      false
+  AfterControlStatement: false
+  AfterEnum:       false
+  AfterFunction:   false
+  AfterNamespace:  false
+  AfterObjCDeclaration: false
+  AfterStruct:     false
+  AfterUnion:      false
+  AfterExternBlock: false
+  BeforeCatch:     false
+  BeforeElse:      false
+  IndentBraces:    false
+  SplitEmptyFunction: true
+  SplitEmptyRecord: true
+  SplitEmptyNamespace: true
+BreakBeforeBinaryOperators: None
+BreakBeforeBraces: Attach
+BreakBeforeInheritanceComma: false
+BreakBeforeTernaryOperators: true
+BreakConstructorInitializersBeforeComma: false
+BreakConstructorInitializers: BeforeColon
+BreakAfterJavaFieldAnnotations: false
+BreakStringLiterals: true
+ColumnLimit:     120
+CommentPragmas:  '^ IWYU pragma:'
+CompactNamespaces: false
+ConstructorInitializerAllOnOneLineOrOnePerLine: true
+ConstructorInitializerIndentWidth: 4
+ContinuationIndentWidth: 4
+Cpp11BracedListStyle: true
+DerivePointerAlignment: true
+DisableFormat:   false
+ExperimentalAutoDetectBinPacking: false
+FixNamespaceComments: true
+ForEachMacros:
+  - foreach
+  - Q_FOREACH
+  - BOOST_FOREACH
+IncludeBlocks:   Preserve
+IncludeCategories:
+  - Regex:           '^<ext/.*\.h>'
+    Priority:        2
+  - Regex:           '^<.*\.h>'
+    Priority:        1
+  - Regex:           '^<.*'
+    Priority:        2
+  - Regex:           '.*'
+    Priority:        3
+IncludeIsMainRegex: '([-_](test|unittest))?$'
+IndentCaseLabels: true
+IndentPPDirectives: None
+IndentWidth:     8 # Modified
+IndentWrappedFunctionNames: false
+JavaScriptQuotes: Leave
+JavaScriptWrapImports: true
+KeepEmptyLinesAtTheStartOfBlocks: false
+MacroBlockBegin: ''
+MacroBlockEnd:   ''
+MaxEmptyLinesToKeep: 1
+NamespaceIndentation: None
+ObjCBlockIndentWidth: 2
+ObjCSpaceAfterProperty: false
+ObjCSpaceBeforeProtocolList: false
+PenaltyBreakAssignment: 2
+PenaltyBreakBeforeFirstCallParameter: 1
+PenaltyBreakComment: 300
+PenaltyBreakFirstLessLess: 120
+PenaltyBreakString: 1000
+PenaltyExcessCharacter: 1000000
+PenaltyReturnTypeOnItsOwnLine: 200
+PointerAlignment: Left
+RawStringFormats:
+  - Delimiter:       pb
+    Language:        TextProto
+    BasedOnStyle:    google
+ReflowComments:  true
+SortIncludes:    true
+SortUsingDeclarations: true
+SpaceAfterCStyleCast: false
+SpaceAfterTemplateKeyword: true
+SpaceBeforeAssignmentOperators: true
+SpaceBeforeParens: ControlStatements
+SpaceInEmptyParentheses: false
+SpacesBeforeTrailingComments: 2
+SpacesInAngles:  false
+SpacesInContainerLiterals: true
+SpacesInCStyleCastParentheses: false
+SpacesInParentheses: false
+SpacesInSquareBrackets: false
+Standard:        Auto
+TabWidth:        8 # Modified
+UseTab:          Always # Modified
+...
+

.github/workflows/format_checks.yml

@@ -0,0 +1,15 @@
+name: Format Checks
+
+on: [push, pull_request]
+
+jobs:
+  format_checks:
+    runs-on: ubuntu-latest
+    container: px4io/px4-dev-clang:2019-10-24
+    steps:
+    - uses: actions/checkout@v1
+    - name: install clang-format-6.0
+      run: apt install -y clang-format-6.0
+    - name: check_format
+      run: ./tools/format.sh 0
+

EKF/AlphaFilter.hpp

@@ -38,34 +38,26 @@
 
 #pragma once
 
-template<typename T>
-class AlphaFilter final
-{
+template <typename T>
+class AlphaFilter final {
 public:
 	AlphaFilter() = default;
 	~AlphaFilter() = default;
 
 	void reset(const T &val) { _x = val; }
 
-	void update(const T &input, float tau, float dt)
-	{
-		const float alpha = dt / tau; 
+	void update(const T &input, float tau, float dt) {
+		const float alpha = dt / tau;
 		update(input, alpha);
 	}
 
-	void update(const T &input, float alpha)
-	{
-		_x = (1.f - alpha) * _x + alpha * input;
-	}
+	void update(const T &input, float alpha) { _x = (1.f - alpha) * _x + alpha * input; }
 
 	// Typical 0.9/0.1 lowpass filter
-	void update(const T &input)
-	{
-		update(input, 0.1f);
-	}
+	void update(const T &input) { update(input, 0.1f); }
 
-	const T& getState() const { return _x; }
+	const T &getState() const { return _x; }
 
 private:
-	T _x{}; ///< current state of the filter
+	T _x{};  ///< current state of the filter
 };

EKF/RingBuffer.h

@@ -42,11 +42,9 @@
 #include <cstring>
 
 template <typename data_type>
-class RingBuffer
-{
+class RingBuffer {
 public:
-	RingBuffer()
-	{
+	RingBuffer() {
 		if (allocate(1)) {
 			// initialize with one empty sample
 			data_type d = {};
@@ -61,8 +59,7 @@ public:
 	RingBuffer(RingBuffer &&) = delete;
 	RingBuffer &operator=(RingBuffer &&) = delete;
 
-	bool allocate(uint8_t size)
-	{
+	bool allocate(uint8_t size) {
 		if (_buffer != nullptr) {
 			delete[] _buffer;
 		}
@@ -78,7 +75,8 @@ public:
 		_head = 0;
 		_tail = 0;
 
-		// set the time elements to zero so that bad data is not retrieved from the buffers
+		// set the time elements to zero so that bad data is not
+		// retrieved from the buffers
 		for (uint8_t index = 0; index < _size; index++) {
 			_buffer[index] = {};
 		}
@@ -88,14 +86,12 @@ public:
 		return true;
 	}
 
-	void unallocate()
-	{
+	void unallocate() {
 		delete[] _buffer;
 		_buffer = nullptr;
 	}
 
-	void push(const data_type &sample)
-	{
+	void push(const data_type &sample) {
 		uint8_t head_new = _head;
 
 		if (!_first_write) {
@@ -123,19 +119,18 @@ public:
 
 	uint8_t get_oldest_index() const { return _tail; }
 
-	bool pop_first_older_than(const uint64_t &timestamp, data_type *sample)
-	{
+	bool pop_first_older_than(const uint64_t &timestamp, data_type *sample) {
 		// start looking from newest observation data
 		for (uint8_t i = 0; i < _size; i++) {
 			int index = (_head - i);
 			index = index < 0 ? _size + index : index;
 
 			if (timestamp >= _buffer[index].time_us && timestamp - _buffer[index].time_us < (uint64_t)1e5) {
-
 				*sample = _buffer[index];
 
-				// Now we can set the tail to the item which comes after the one we removed
-				// since we don't want to have any older data in the buffer
+				// Now we can set the tail to the item which
+				// comes after the one we removed since we don't
+				// want to have any older data in the buffer
 				if (index == _head) {
 					_tail = _head;
 					_first_write = true;
@@ -150,7 +145,8 @@ public:
 			}
 
 			if (index == _tail) {
-				// we have reached the tail and haven't got a match
+				// we have reached the tail and haven't got a
+				// match
 				return false;
 			}
 		}

Makefile

@@ -39,6 +39,8 @@
 FIRST_ARG := $(firstword $(MAKECMDGOALS))
 ARGS := $(wordlist 2,$(words $(MAKECMDGOALS)),$(MAKECMDGOALS))
 j ?= 4
+BLUE='\033[1;36m'
+NC='\033[0m' # No Color
 
 NINJA_BIN := ninja
 ifndef NO_NINJA_BUILD
@@ -95,7 +97,7 @@ doxygen:
 # Testing
 # --------------------------------------------------------------------
 
-.PHONY: test_build test test_EKF
+.PHONY: test_build test
 
 test_build:
 	@$(call cmake-build,$@,$(SRC_DIR), "-DBUILD_TESTING=ON")
@@ -124,6 +126,22 @@ coverage_html: coverage_build
 coverage_html_view: coverage_build
 	@cmake --build $(SRC_DIR)/build/coverage_build --target coverage_html_view
 
+# Code formatting
+# --------------------------------------------------------------------
+.PHONY: check_format format clang-format
+
+clang-format:
+	@echo -e ${BLUE}Check clang-format-6.0 installation${NC}
+	@if ! hash clang-format-6.0; then sudo apt install clang-format-6.0 -y; fi
+
+check_format: clang-format
+	@echo -e ${BLUE}Checking formatting with clang-format${NC}
+	@$(SRC_DIR)/tools/format.sh 0
+
+format: clang-format
+	@echo -e ${BLUE}Formatting with clang-format${NC}
+	@$(SRC_DIR)/tools/format.sh 1
+
 # Cleanup
 # --------------------------------------------------------------------
 .PHONY: clean distclean

tools/format.sh

@@ -0,0 +1,34 @@
+#!/bin/bash
+do_format=$1
+files_to_format="""
+EKF/AlphaFilter.hpp
+EKF/RingBuffer.h
+"""
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+YELLOW='\033[1;33m'
+NC='\033[0m' # No Color
+
+if ! hash clang-format-6.0
+then
+    echo -e ${RED}Error: No clang-format-6.0 installed${NC}
+    exit 1
+fi
+
+if [[ $do_format -eq 1 ]]
+then
+    # formatting
+    clang-format-6.0 -i -style=file ${files_to_format}
+    echo -e ${GREEN}Formatting finished${NC}
+else
+    # checking format...
+    clang-format-6.0 -style=file  -output-replacements-xml ${files_to_format} | grep -c "<replacement " > /dev/null
+    if [[ $? -eq 0 ]]
+    then
+        echo -e ${RED}Error: need to format${NC}
+        echo -e ${YELLOW}From cmake build directory run: 'make format'${NC}
+        exit 1
+    fi
+    echo -e ${GREEN}no formatting needed${NC}
+    exit 0
+fi