Add CMake build flag for generating Python bindings

.github/CHANGELOG.md

@@ -1,4 +1,24 @@
-## Release 0.1.0
+## Release 0.2.0 (development release)
+
+### New features since last release
+
+* Running CMake with `-DBUILD_PYTHON=ON` now generates Python bindings within a `jet` package. [(#1)](https://github.com/XanaduAI/jet/pull/1)
+
+### Improvements
+
+### Breaking Changes
+
+### Bug Fixes
+
+### Documentation
+
+### Contributors
+
+This release contains contributions from (in alphabetical order):
+
+[Mikhail Andrenkov](https://github.com/Mandrenkov) and [Jack Brown](https://github.com/brownj85).
+
+## Release 0.1.0 (current release)
 
 ### New features since last release
 

.github/workflows/format.yml

@@ -6,11 +6,12 @@ on:
       - main
     paths:
       - "include/**"
+      - "python/**"
       - "test/**"
 
 jobs:
-  format:
-    name: Format
+  format-cpp:
+    name: Format (C++)
     runs-on: ubuntu-20.04
 
     steps:
@@ -26,4 +27,30 @@ jobs:
         uses: actions/checkout@v2
 
       - name: Run formatter
-        run: ./bin/format --check include test
+        run: ./bin/format --check include python/src test
+
+  format-python:
+    name: Format (Python)
+    runs-on: ubuntu-20.04
+
+    steps:
+      - name: Cancel previous runs
+        uses: styfle/[email protected]
+        with:
+          access_token: ${{ github.token }}
+
+      - name: Install dependencies
+        run: sudo apt update && sudo apt -y install python3
+
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Create virtual environment
+        run: |
+          cd python
+          make setup
+
+      - name: Run formatter
+        run: |
+          cd python
+          make format check=1

.github/workflows/python.yml

@@ -0,0 +1,85 @@
+name: Python
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+    paths-ignore:
+      - ".github/**"
+      - "docs/**"
+      - "README.rst"
+
+jobs:
+  test-ubuntu:
+    name: Build (Ubuntu)
+    runs-on: ubuntu-20.04
+
+    steps:
+      - name: Cancel previous runs
+        uses: styfle/[email protected]
+        with:
+          access_token: ${{ github.token }}
+
+      - name: Install dependencies
+        run: sudo apt install -y libopenblas-dev python3.8-dev
+
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Initialize build directory
+        run: |
+          mkdir build
+          cd build
+          cmake -DBUILD_PYTHON=ON ../
+
+      - name: Generate Python bindings
+        run: |
+          cd build
+          make -j`nproc`
+
+      - name: Create virtual environment
+        run: |
+          cd python
+          make setup
+
+      - name: Run tests
+        run: |
+          cd python
+          make test
+
+  test-macos:
+    name: Build (MacOS)
+    runs-on: macos-10.15
+
+    steps:
+      - name: Cancel previous runs
+        uses: styfle/[email protected]
+        with:
+          access_token: ${{ github.token }}
+
+      - name: Install dependencies
+        run: brew install libomp
+
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Initialize build directory
+        run: |
+          mkdir build
+          cd build
+          cmake -DBUILD_PYTHON=ON ../
+
+      - name: Generate Python bindings
+        run: |
+          cd build
+          make -j`sysctl -n hw.physicalcpu`
+
+      - name: Create virtual environment
+        run: |
+          cd python
+          make setup
+
+      - name: Run tests
+        run: |
+          cd python
+          make test

.gitignore

@@ -41,8 +41,9 @@ build
 # CMake build artifacts
 include/jet/CmakeMacros.hpp
 
-# Python virtualenv
+# Python
 .venv
+__pycache__
 
 # Sphinx documentation
 docs/__pycache__/*

CMakeLists.txt

@@ -1,7 +1,7 @@
 ##########################
 ## Set Project version
 ##########################
-cmake_minimum_required(VERSION 3.13)
+cmake_minimum_required(VERSION 3.14)
 set(JET_LOGO "
       ▄▄     ▄▄▄▄▄▄▄▄    ▄▄▄▄▄▄▄▄ 
       ██     ██▀▀▀▀▀▀    ▀▀▀██▀▀▀ 
@@ -30,11 +30,12 @@ option(ENABLE_NATIVE "Enable native build tuning" OFF)
 option(ENABLE_IPO "Enable interprocedural/link-time optimisation" OFF)
 
 # Build options
+option(BUILD_PYTHON "Generate Python bindings" OFF)
+option(BUILD_TESTS "Build tests" OFF)
 if(NOT CMAKE_BUILD_TYPE)
     set(CMAKE_BUILD_TYPE "Release" CACHE STRING
             "Default build type: Release" FORCE)
 endif()
-option(BUILD_TESTS "Build tests" OFF)
 
 ##########################
 ## Enfore Compiler Support
@@ -77,18 +78,18 @@ list(APPEND CMAKE_MODULE_PATH "${PROJECT_SOURCE_DIR}/cmake")
 find_package(MKL QUIET)
 
 if(MKL_FOUND)
-    add_definitions("-DENABLE_MKL")
-    set(BLAS_INCLUDE_DIRS "${MKL_INCLUDE_DIR}")
-    set(BLAS_LIBRARIES ${MKL_LIBRARY})
+  add_definitions("-DENABLE_MKL")
+  set(BLAS_INCLUDE_DIRS "${MKL_INCLUDE_DIR}")
+  set(BLAS_LIBRARIES ${MKL_LIBRARY})
 else()
-    find_package(CBLAS REQUIRED)
-    set(BLAS_LIBRARIES ${CBLAS_LIBRARIES})
-    set(BLAS_INCLUDE_DIRS ${CBLAS_INCLUDE_DIRS})
+  find_package(CBLAS REQUIRED)
+  set(BLAS_LIBRARIES ${CBLAS_LIBRARIES})
+  set(BLAS_INCLUDE_DIRS ${CBLAS_INCLUDE_DIRS})
 endif()
 
 
 ##########################
-## Fetch Taskflow
+## Fetch dependencies
 ##########################
 Include(FetchContent)
 
@@ -98,30 +99,20 @@ FetchContent_Declare(
   GIT_TAG        v3.1.0
 )
 
-# FetchContent_MakeAvailable() requires CMake 3.14 or newer.
-FetchContent_GetProperties(Taskflow)
-if(NOT Taskflow_POPULATED)
-  FetchContent_Populate(Taskflow)
-  # Don't build the Taskflow tests or examples.
-  set(TF_BUILD_EXAMPLES OFF CACHE INTERNAL "Build Taskflow examples")
-  set(TF_BUILD_TESTS OFF CACHE INTERNAL "Build Taskflow tests")
-  add_subdirectory(${taskflow_SOURCE_DIR} ${taskflow_BINARY_DIR})
-endif()
+# Don't build the Taskflow examples or tests.
+set(TF_BUILD_EXAMPLES OFF CACHE INTERNAL "Build Taskflow examples")
+set(TF_BUILD_TESTS OFF CACHE INTERNAL "Build Taskflow tests")
 
-find_package(OpenMP QUIET)
+FetchContent_MakeAvailable(Taskflow)
 
-message(STATUS "CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
-message(STATUS "BLAS_LIBRARIES: ${BLAS_LIBRARIES}")
-message(STATUS "BLAS_INCLUDE_DIRS: ${BLAS_INCLUDE_DIRS}")
-message(STATUS "ENABLE_NATIVE: ${ENABLE_NATIVE}")
-message(STATUS "ENABLE_IPO: ${ENABLE_IPO}")
+find_package(OpenMP QUIET)
 
 ##########################
 ## Create Jet target
 ##########################
 
 add_library(Jet INTERFACE)
-target_include_directories(Jet INTERFACE    
+target_include_directories(Jet INTERFACE
     $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include> 
     ${BLAS_INCLUDE_DIRS}
 )
@@ -132,30 +123,52 @@ target_link_libraries(Jet INTERFACE ${BLAS_LIBRARIES} Taskflow)
 ## Compile options
 ##########################
 
-if (ENABLE_OPENMP AND OPENMP_FOUND)
-    target_link_libraries(Jet INTERFACE OpenMP::OpenMP_CXX)
+if(ENABLE_OPENMP AND OPENMP_FOUND)
+  target_link_libraries(Jet INTERFACE OpenMP::OpenMP_CXX)
 elseif (ENABLE_OPENMP AND NOT OPENMP_FOUND)
-    message(FATAL_ERROR "\nOpenMP is enabled but could not be found")
+  message(FATAL_ERROR "\nOpenMP is enabled but could not be found")
 endif()
+
 if(ENABLE_SANITIZERS)
-    target_compile_options(Jet INTERFACE -g -fsanitize=address,undefined)
-    target_link_options(Jet INTERFACE -fsanitize=address,undefined)
+  target_compile_options(Jet INTERFACE -g -fsanitize=address,undefined)
+  target_link_options(Jet INTERFACE -fsanitize=address,undefined)
 endif()
+
 if(ENABLE_WARNINGS)
-    target_compile_options(Jet INTERFACE -Wall -Wextra -Werror)
+  target_compile_options(Jet INTERFACE -Wall -Wextra -Werror)
 endif()
+
 if(ENABLE_NATIVE)
-    target_compile_options(Jet INTERFACE -march=native)
+  target_compile_options(Jet INTERFACE -march=native)
 endif()
+
 if(ENABLE_IPO)
-    target_compile_options(Jet INTERFACE -flto)
+  target_compile_options(Jet INTERFACE -flto)
 endif()
 
 ##########################
-## Build tests
+## Report
+##########################
+
+message(STATUS "BLAS_INCLUDE_DIRS: ${BLAS_INCLUDE_DIRS}")
+message(STATUS "BLAS_LIBRARIES: ${BLAS_LIBRARIES}")
+message(STATUS "BUILD_PYTHON: ${BUILD_PYTHON}")
+message(STATUS "BUILD_TESTS: ${BUILD_TESTS}")
+message(STATUS "CMAKE_BUILD_TYPE: ${CMAKE_BUILD_TYPE}")
+message(STATUS "ENABLE_IPO: ${ENABLE_IPO}")
+message(STATUS "ENABLE_NATIVE: ${ENABLE_NATIVE}")
+message(STATUS "ENABLE_SANITIZERS: ${ENABLE_SANITIZERS}")
+message(STATUS "ENABLE_WARNINGS: ${ENABLE_WARNINGS}")
+
+##########################
+## Build targets
 ##########################
 
+if(BUILD_PYTHON)
+  add_subdirectory(python)
+endif()
+
 if(BUILD_TESTS)
-    enable_testing()
-    add_subdirectory(test)
+  enable_testing()
+  add_subdirectory(test)
 endif(BUILD_TESTS)

Makefile

@@ -30,9 +30,9 @@ help:
 .PHONY: format
 format:
 ifdef check
-	./bin/format --check include test
+	./bin/format --check include python/src test
 else
-	./bin/format include test
+	./bin/format include python/src test
 endif
 
 

python/CMakeLists.txt

@@ -0,0 +1,14 @@
+Include(FetchContent)
+
+FetchContent_Declare(
+    Pybind11
+    GIT_REPOSITORY https://github.com/pybind/pybind11.git
+    GIT_TAG        v2.6.2
+)
+
+FetchContent_MakeAvailable(Pybind11)
+
+# The following command also creates a CMake target called "jet".
+pybind11_add_module(jet src/Python.cpp)
+
+target_link_libraries(jet PRIVATE Jet)