Satish Kumar

This commit **reverts** a previous change that removed constants from the **Thrift Python mutable types codegen**, thereby **restoring the generation and availability of constants** within mutable Thrift types. The `thrift/lib/python` test suites for `adapter`, `lists`, and `maps` are updated to correctly reference and utilize these re-introduced constants, adjusting expectations for functions like `DatetimeAdapter_from_thrift` and using `self.lists_types` and `self.maps_types`. This **maintenance** action ensures the **Thrift Python library** correctly handles mutable type constants, correcting an earlier modification that proved problematic.

This commit **refactors the Thrift Python codegen** to **prevent the generation of constants** within `thrift_mutable_types`. Previously, mutable constants could allow unexpected in-place modifications of nested values, but analysis confirmed no production code relied on constants from this specific mutable generation. This **maintenance** change primarily affects the **Thrift compiler's Python templates** (`types.mustache`, `types_pyi.mustache`), ensuring that constants are no longer generated when mutable types are enabled. Consequently, **Thrift Python tests** in `thrift/lib/python/test/` are updated to explicitly use immutable constants, enhancing the overall correctness and safety of generated Thrift code by removing a potentially problematic feature.

This commit performs a **maintenance refactoring** within the **Thrift Python code generation templates**, specifically `thrift/compiler/generate/templates/python/common/common.mustache`. It **removes expired `DO_BEFORE` annotations** that tracked open design questions regarding `alias_prefix` symbol risk and immutable types override behavior in the **Python codegen**. After a year of observation, these concerns did not materialize, leading to the **stabilization of the current behavior** for these aspects. This cleanup confirms the acceptance of existing design choices and removes unnecessary future considerations for the **Thrift Python compiler**.

This commit **resolves a build failure** for **C++ extensions** compiled via `setuptools` by explicitly enforcing the **C++20 standard**. Previously, the `build_ext` command in `setup.py` did not automatically include the `-std=c++20` flag, leading to compilation errors for components dependent on Folly headers. By adding `extra_compile_args=["-std=c++20"]` to the relevant `Extension` objects, this **maintenance update** ensures consistent and successful compilation across all build environments, particularly for the **Python integration layer**.

This commit **removes the proxygen dependency** from the **fbthrift-python build system**, streamlining its compilation process. It involves deleting the `proxygen-python` manifest, updating `fbthrift-python`'s dependencies, and modifying `CMakeLists.txt` and Cython include paths to eliminate all references to `proxygen`. As a result of this **dependency removal and build system cleanup**, `http2_helper` files that relied on `proxygen` are now explicitly skipped, simplifying the overall build and reducing the external dependency footprint for `fbthrift-python`.

This commit **removes the proxygen dependency** from the **fbthrift-python build system**, streamlining its compilation process. It involves deleting the `proxygen-python` manifest, updating `fbthrift-python`'s dependencies, and modifying `CMakeLists.txt` and Cython include paths to eliminate all references to `proxygen`. As a result of this **dependency removal and build system cleanup**, `http2_helper` files that relied on `proxygen` are now explicitly skipped, simplifying the overall build and reducing the external dependency footprint for `fbthrift-python`.

This commit **refactors the `fbthrift-python` build system** by **removing its dependency on `proxygen`**, aiming to simplify and optimize the compilation process. It achieves this by deleting `proxygen-python` manifests, updating dependency lists in `CMakeLists.txt`, and adjusting Cython include paths. Consequently, `http2_helper` files, which relied on `proxygen`, are now explicitly skipped during the `fbthrift-python` build. This **dependency management** effort also includes a minor **maintenance** fix, adding a guard to prevent `--disable-shared` injection when `--enable-shared` is already specified, ensuring more robust build configurations and **reducing unnecessary dependencies** for `fbthrift-python`.

Isolate Python dependency tree from native build system

This commit **refactors the build system** to **isolate the Python dependency tree** from the native C++ build process, addressing issues where Python builds pulled in unnecessary C++ dependencies like `proxygen`. It introduces a new `libaio-python` manifest and updates existing Python manifests (`fbthrift-python`, `folly-python`, `fizz-python`, `zlib-python`, `libiberty-python`) to depend on their Python-specific variants, **streamlining dependency management** and **improving build stability** for Python components. This work also includes a **bug fix** for the `zlib-python` download URL and adds **build status badges** for Python builds, enhancing overall clarity and efficiency.

This commit **refactors the build system** to **isolate Python dependency management** from the native C++ build process, addressing issues where `fbthrift-python` builds were unnecessarily brittle due to mixed dependencies. It introduces a new `libaio-python` manifest and updates existing Python-specific manifests (`fbthrift-python`, `folly-python`, `fizz-python`, `zlib-python`, `libiberty-python`) to depend on their respective Python variants, effectively **removing the unnecessary `proxygen` dependency** by excluding the `http2_helper` test extension. This **improves the robustness and clarity** of Python builds by preventing conflicts with C++ library versions and configurations. Additionally, it **fixes the download URL for `zlib-python`** and **updates the `README.md`** with new build status badges for the Python builds.

This commit introduces **Python language support** to the **Thrift CMake macros**, enabling the generation of Python code from Thrift definitions. It extends `thrift_generate`, `thrift_object`, and `thrift_library` to accept `language="python"`, allowing `thrift_generate` to invoke `mstch_python` and produce `.py` and `.pyi` files. A new `NAMESPACE` parameter facilitates correct output directory structuring for **PEP 420 namespace packages**, while `thrift_object` and `thrift_library` now create custom build targets instead of C++ object libraries for Python. This **new capability** significantly streamlines the build process for **Thrift-Python projects** within the CMake ecosystem.

This commit **adds comprehensive unit tests** for the **Thrift Python utility libraries**, specifically targeting the `randomizer` and `fuzzer` components. It introduces new tests in `thrift/lib/py/util/tests/test_randomizer.py` to validate utility functions like binary conversion and dictionary updates, and extensive parameterized tests in `thrift/lib/py/util/tests/test_fuzzer.py` to ensure the correctness of fuzzer constraints across all data types, including booleans, enums, integers, doubles, strings, collections, maps, and structs. This **enhances code quality and reliability** for the `thrift-python` ecosystem, serving as a crucial **prerequisite for enabling broader `thrift-python` support**.

Add source files absent from build

This commit **removes the `disable_abstract_types` compiler option** from the **Thrift Python generator**, making abstract types unconditionally enabled. This **cleanup and refactoring** effort reflects the stabilization of abstract types, eliminating the need for a disabling flag within the compiler. It updates the compiler help text, modifies `python.bzl` docstring examples to use `disable_field_cache` instead, and deletes associated `abstract_types_flags` test files and BUCK targets. The change simplifies the compiler interface and removes deprecated infrastructure, ensuring abstract types are a permanent feature for Python code generation.

This commit **suppresses an unused import warning** within the **Thrift Python library tests**. It specifically adds a `noqa: F401` comment to an import statement in `thrift/lib/python/test/special_cases_test.py` that is intentionally unused. This **maintenance** change prevents a false positive linting warning, thereby improving code cleanliness and ensuring that automated checks focus on genuine issues rather than expected deviations.

This commit enhances **test coverage** for the **`thrift-python` compiler** by adding a new `typedef` fixture that uses a Python reserved keyword. Specifically, it introduces `typedef i64 and` to the `py-reserved` fixture in `test.thrift`, demonstrating how such definitions lead to **invalid Python syntax** (e.g., `and = int`) in the generated code. This **maintenance** change exposes a critical bug where the compiler fails to properly handle reserved keywords in `typedef` names, resulting in uncompilable Python output. The added fixture is crucial for validating future fixes to this code generation issue within the **`thrift-python`** module.

This commit **fixes a code generation bug** in the **Thrift Python compiler** where `typedef` names clashing with Python reserved keywords resulted in invalid generated Python syntax. Previously, a `typedef` like `typedef i64 and` would incorrectly generate `and = builtins.int`. The **Python code generation templates** have been updated to use `typedef.py_name`, which now correctly escapes these keywords by appending an underscore (e.g., `and_ = builtins.int`). This **maintenance fix** ensures that all **generated Python Thrift code** is syntactically valid, preventing compilation failures for users defining such `typedefs`, and is validated by new test cases.

Add @generated header to CMake files

This commit **fixes a name collision bug** in the **Thrift Python code generator** that previously caused **Pyre type-check failures** for services named `Service`. Specifically, the generated `ServiceInterface` class would shadow the imported base class, preventing `super().getFunctionTable()` from resolving correctly. To resolve this, the base `ServiceInterface` import in `services.mustache` is now **aliased to `_fbthrift_ServiceInterface`**, aligning with existing internal naming conventions. This **refactoring** ensures correct inheritance and type resolution for all generated Python Thrift services, improving the reliability of the generated code.

This commit **enhances the `generate_cmake.py` script** to properly integrate the **Python subdirectory** into the Folly CMake build system. It modifies the generator to no longer skip the `python` directory and marks it for specific handling within the CMake generation process. Crucially, it introduces a mechanism to **conditionally include the `python` subdirectory** using an `if(PYTHON_EXTENSIONS)` guard, allowing users to enable or disable Python extensions during the Folly build. This **integration work** streamlines the build configuration for Python components and provides greater flexibility for downstream consumers of Folly.