+
+== Testing
+
+[[test-env]]
+=== Environment
+
+Running `make check` in the build directory (regardless of whether the build is
+in-tree or out-of-tree) automatically sets up the appropriate environment for
+tests to run in, so nothing more is needed.
+
+If building in-tree, you can run single tests from the tree directly:
+
+----
+$ ./tests/plugins/sink.text.pretty/test_enum
+----
+
+If building out-of-tree, you can get the appropriate environment by sourcing
+the `tests/utils/env.sh` file residing in the build directory against which you
+want to run tests.
+
+----
+$ source /path/to/my/build/tests/utils/env.sh
+$ ./tests/plugins/sink.text.pretty/test_enum
+----
+
+==== Python
+
+You can use the `tests/utils/run_python_bt2` script to run any command
+within an environment making the build's `bt2` Python package available.
+
+`run_python_bt2` uses <<test-env,`utils.sh`>> which needs to know the
+build directory, so make sure you set the `BT_TESTS_BUILDDIR`
+environment variable correctly _if you build out of tree_, for example:
+
+----
+$ export BT_TESTS_BUILDDIR=/path/to/build/babeltrace/tests
+----
+
+You can run any command which needs the `bt2` Python package through
+`run_python_bt2`, for example:
+
+----
+$ ./tests/utils/run_python_bt2 ipython3
+----
+
+=== Report format
+
+All test scripts output the test results following the
+https://testanything.org/[Test Anything Protocol] (TAP) format.
+
+The TAP format has two mechanisms to print additional information about
+a test:
+
+* Print a line starting with `#` to the standard output.
++
+This is usually done with the `diag()` C function or the `diag` shell
+function.
+
+* Print to the standard error.
+
+=== Python bindings
+
+The `bt2` Python package tests are located in
+`tests/bindings/python/bt2`.
+
+==== Python test runner
+
+`tests/utils/python/testrunner.py` is {bt2}'s Python test runner
+which loads Python files containing unit tests, finds all the test
+cases, and runs the tests, producing a TAP report.
+
+You can see the test runner command's help with:
+
+----
+$ python3 ./tests/utils/python/testrunner.py --help
+----
+
+By default, the test runner reports failing tests (TAP's `not{nbsp}ok`
+line), but continues to run other tests. You can use the `--failfast`
+option to make the test runner fail as soon as a test fails.
+
+==== Guides
+
+To run all the `bt2` Python package tests:
+
+* Run:
++
+----
+$ ./tests/utils/run_python_bt2 ./tests/bindings/python/bt2/test_python_bt2
+----
++
+or:
++
+----
+$ ./tests/utils/run_python_bt2 python3 ./tests/utils/python/testrunner.py \
+ ./tests/bindings/python/bt2/ -p '*.py'
+----
+
+To run **all the tests** in a test module (for example,
+`test_value.py`):
+
+* Run:
++
+----
+$ ./tests/utils/run_python_bt2 python3 ./tests/utils/python/testrunner.py \
+ ./tests/bindings/python/bt2 -t test_value
+----
+
+To run a **specific test case** (for example, `RealValueTestCase` within
+`test_value.py`):
+
+* Run:
++
+----
+$ ./tests/utils/run_python_bt2 python3 ./tests/utils/python/testrunner.py \
+ ./tests/bindings/python/bt2/ -t test_value.RealValueTestCase
+----
+
+To run a **specific test** (for example,
+`RealValueTestCase.test_assign_pos_int` within `test_value.py`):
+
+* Run:
++
+----
+$ ./tests/utils/run_python_bt2 python3 ./tests/utils/python/testrunner.py \
+ ./tests/bindings/python/bt2/ -t test_value.RealValueTestCase.test_assign_pos_int
+----
+
+== {cpp} usage
+
+Some parts of {bt2} are written in {cpp}.
+
+This section shows what's important to know about {cpp} to contribute
+to {bt2}.
+
+[IMPORTANT]
+====
+{bt2} only has {cpp} sources for _internal_ code.
+
+In other words, libbabeltrace2 _must_ expose a pure C99 API to preserve
+ABI compatibility over time.
+====
+
+=== Standard and dependencies
+
+The {bt2} project is configured to use the {cpp11} standard.
+
+{cpp11} makes it possible to build {bt2} with a broad range of
+compilers, from GCC{nbsp}4.8 and Clang{nbsp}3.3.
+
+=== Automake/Libtool requirements
+
+To add a {cpp} source file to a part of the project, use the `.cpp`
+extension and add it to the list of source files in `Makefile.am` as
+usual.
+
+If a program or a shared library has a direct {cpp} source file, then
+Libtool uses the {cpp} linker to create the result, dynamically
+linking important runtime libraries such as libstdc++ and libgcc_s.
+
+Because a Libtool _convenience library_ is just an archive (`.a`), it's
+_not_ dynamically linked to runtime libraries, even if one of its direct
+sources is a {cpp} file. This means that for each program or shared
+library named `my_target` in `Makefile.am` which is linked to a
+convenience library having {cpp} sources (recursively), you _must_ do
+one of:
+
+* Have at least one direct {cpp} source file in the
+ `+*_my_target_SOURCES+` list.
+
+* Add:
++
+----
+nodist_EXTRA_my_target_SOURCES = dummy.cpp
+----
++
+See
+https://www.gnu.org/software/automake/manual/automake.html#Libtool-Convenience-Libraries[Libtool
+Convenience Libraries] to learn more.
+
+For a given program or library, you _cannot_ have a C{nbsp}file and a
+{cpp}{nbsp}file having the same name, for example `list.c` and
+`list.cpp`.
+
+=== Coding style
+
+==== Whitespaces, indentation, and line breaks
+
+All the project's {cpp} files follow the
+https://clang.llvm.org/docs/ClangFormat.html[clang-format]
+https://clang.llvm.org/docs/ClangFormatStyleOptions.html[style] of the
+`.clang-format` file for whitespaces, indentation, and line breaks.
+
+You _must_ format modified and new {cpp} files with clang-format before
+you create a contribution patch.
+
+You need clang-format{nbsp}13 to use the project's `.clang-format` file.
+
+To automatically format all the project's {cpp} files, run:
+
+----
+$ ./tools/format-cpp
+----
+
+Use the `FORMATTER` environment variable to override the default
+formatter (`clang-format{nbsp}-i`):
+
+----
+$ FORMATTER='clang-format-10 -i' ./tools/format-cpp
+----
+
+==== Naming
+
+* Use camel case with a lowercase first letter for:
+** Variable names: `size`, `objSize`.
+** Function/method names: `size()`, `formatAndPrint()`.
+
+* Use camel case with an uppercase first letter for:
+** Types: `Pistachio`, `NutManager`.
+** Template parameters: `PlanetT`, `TotalSize`.
+
+* Use snake case with uppercase letters for:
+** Definition/macro names: `MARK_AS_UNUSED()`, `SOME_FEATURE_EXISTS`.
+** Enumerators: `Type::SIGNED_INT`, `Scope::FUNCTION`.
+
+* Use only lowercase letters and digits for namespaces: `mylib`, `bt2`.
+
+* Use the suffix `T` for type template parameters:
++
+[source,cpp]
+----
+template <typename NameT, typename ItemT>
+----
+
+* Name a template parameter pack `Args`.
++
+[source,cpp]
+----
+template <typename NameT, typename... Args>
+----
+
+* Use an underscore prefix for private and protected methods and member
+ type names: `_tryConnect()`, `_NodeType`.
+
+* Use the prefix `_m` for private and protected member variable names:
+ `_mLogger`, `_mSize`, `_mFieldClass`.
+
+* Name setters and getters like the property name, without `set` and
+ `get` prefixes.
+
+* Use the `is` or `has` prefix, if possible, to name the functions which
+ return `bool`.
+
+=== Coding convention
+
+In general, the project's contributors make an effort to follow,
+for {cpp11} code:
+
+* The
+ https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md[{cpp} Core Guidelines].
+
+* Scott Meyers's
+ "`https://www.oreilly.com/library/view/effective-modern-c/9781491908419/[Effective Modern {cpp}]`".
+
+Here are a few important reminders:
+
+* Namespace your code.
+
+* Create one header/source file pair per class when possible.
++
+For a class named `MyClass`, name the corresponding files `my-class.hpp`
+and `my-class.cpp`.
+
+* When defining a class, put constructors as the first methods, whatever
+ their access (public/protected/private), then the destructor, and then
+ the rest.
+
+* Declare variables as close to where they are used as possible.
+
+* Use `auto` when possible.
+
+* Use `const` as much as possible, even for pointer
+ (`+const char* const+`) and numeric values (`const unsigned int`)
+ which never need to change.
+
+* Implement simple setters, getters, and one-liners in header files and
+ everything else that's not a template in source files.
+
+* Make methods `const noexcept` or `const` as much as possible.
+
+* Make constructors `explicit` unless you really need an implicit
+ constructor (which is rare).
+
+* Use `std::unique_ptr` to manage memory when possible.
++
+However, use references (`+*my_unique_ptr+`) and raw pointers
+(`+my_unique_ptr.get()+`) when not transferring ownership.
+
+* Use `nullptr`, not `NULL` nor 0.
+
+* Return by value (rvalue) instead of by output parameter (non-const
+ lvalue reference), even complex objects, unless you can prove that the
+ performance is improved when returning by parameter.
+
+* For a function parameter or a return value of which the type needs to
+ be a reference or pointer, use:
++
+If the value is mandatory:::
+ A reference.
+If the value is optional:::
+ A raw pointer.
+
+* Don't use `+std::move()+` when you already have an rvalue, which
+ means:
+** Don't write `+return std::move(...);+` as this can interfere with
+ RVO.
+** Don't use `+std::move()+` with a function call
+ (`+std::move(func())+`).
+
+* For each possible move/copy constructor or assignment operator, do one
+ of:
+** Write a custom one.
+** Mark it as defaulted (`default`)
+** Mark it as deleted (`delete`).
+
+* Use scoped enumerations (`+enum class+`).
+
+* Mark classes known to be final with the `final` keyword.
+
+* Use type aliases (`using`), not type definitions (`typedef`).
+
+* Use anonymous namespaces for local functions instead of `static`.
+
+* Don't pollute the global namespace:
+** Don't use `using namespace xyz` anywhere.
+** Use only namespace aliases in source files (`.cpp`), trying to
+ use them in the smallest possible scope (function, or even smaller).
+
+* Return a structure with named members instead of a generic container
+ such as `std::pair` or `std::tuple`.
+
+* When a class inherits a base class with virtual methods, use the
+ `override` keyword to mark overridden virtual methods, and do not use
+ the `virtual` keyword again.
+
+* Define overloaded operators only if their meaning is obvious,
+ unsurprising, and consistent with the corresponding built-in
+ operators.
++
+For example, use `+|+` as a bitwise- or logical-or, not as a shell-style
+pipe.
+
+* Use RAII wrappers when managing system resources or interacting with
+ C{nbsp}libraries.
++
+In other words, don't rely on ``goto``s and error labels to clean up as
+you would do in{nbsp}C.
++
+Use the RAII, Luke.
+
+* Throw an exception when there's an unexpected, exceptional condition,
+ https://isocpp.org/wiki/faq/exceptions#ctors-can-throw[including from
+ a constructor], instead of returning a status code.
+
+* Accept a by-value parameter and move it (when it's moveable) when you
+ intend to copy it anyway.
++
+You can do this with most STL containers.
++
+Example:
++
+[source,cpp]
+----
+void Obj::doSomething(std::string str)
+{
+ _mName = std::move(str);
+ // ...
+}
+----
+
+.`baby.hpp`
+====
+This example shows a {cpp} header which follows the {bt2} {cpp} coding
+convention.
+
+[source,cpp]
+----
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright 2020 Harry Burnett <hburnett@reese.choco>
+ */
+
+#ifndef BABELTRACE_BABY_HPP
+#define BABELTRACE_BABY_HPP
+
+#include <string>
+#include <unordered_set>
+#include <utility>
+
+namespace life {
+
+class Toy;
+
+/*
+ * A baby is a little human.
+ */
+class Baby : public Human
+{
+public:
+ using Toys = std::unordered_set<Toy>;
+
+ enum class Gender
+ {
+ MALE,
+ FEMALE,
+ UNKNOWN,
+ };
+
+ Baby() = default;
+ explicit Baby(const Toys& toys);
+ Baby(const Baby&) = delete;
+ Baby(Baby&&) = delete;
+ Baby& operator=(const Baby&) = delete;
+ Baby& operator=(Baby&&) = delete;
+
+protected:
+ explicit Baby(Gender initialGender = Gender::UNKNOWN);
+
+public:
+ /*
+ * Eats `weight` grams of food.
+ */
+ void eat(unsigned long weight);
+
+ /*
+ * Sleeps for `duration` seconds.
+ */
+ void sleep(double duration);
+
+ /*
+ * Sets this baby's name to `name`.
+ */
+ void name(std::string name)
+ {
+ _mName = std::move(name);
+ }
+
+ /*
+ * This baby's name.
+ */
+ const std::string& name() const noexcept
+ {
+ return _mName;
+ }
+
+protected:
+ void _addTeeth(unsigned long index);
+ void _grow(double size) override;
+
+private:
+ std::string _mName {"Paul"};
+ Toys _mToys;
+};
+
+} // namespace life
+
+#endif // BABELTRACE_BABY_HPP
+----
+====
projects / babeltrace.git / blobdiff