Revert "Remove boost-filesystem fallback now that PEGTL depends on std::filesystem"

This reverts commit 8fc5053.

Author: wravery

README.md

@@ -45,7 +45,7 @@ The easiest way to get all of these and to build `cppgraphqlgen` in one step is
 [microsoft/vcpkg](https://github.com/microsoft/vcpkg). To install with vcpkg, make sure you've pulled the latest version
 and then run `vcpkg install cppgraphqlgen` (or `cppgraphqlgen:x64-windows`, `cppgraphqlgen:x86-windows-static`, etc.
 depending on your platform). To install just the dependencies and work in a clone of this repo, you'll need some subset
-of `vcpkg install pegtl boost-program-options rapidjson gtest`. It works for Windows, Linux, and Mac,
+of `vcpkg install pegtl boost-program-options boost-filesystem rapidjson gtest`. It works for Windows, Linux, and Mac,
 but if you want to try building for another platform (e.g. Android or iOS), you'll need to do more of this manually.
 
 Manual installation will work best if you clone the GitHub repos for each of the dependencies and follow the installation
@@ -85,6 +85,11 @@ do that.
 
 I'm using [Boost](https://www.boost.org/doc/libs/1_69_0/more/getting_started/index.html) for `schemagen`:
 
+- C++17 std::filesystem support on Unix:
+[Boost.Filesystem](https://www.boost.org/doc/libs/1_69_0/libs/filesystem/doc/index.htm). Most of the default C++
+compilers on Linux still have `std::filesystem` from C++17 in an experimental directory and require an extra
+library. The standard just adopted the Boost library, so on Unix systems I have an `#ifdef` which redirects back to
+it for the time being.
 - Command line handling: [Boost.Program_options](https://www.boost.org/doc/libs/1_69_0/doc/html/program_options.html).
 Run `schemagen -?` to get a list of options. Many of the files in the [samples](samples/) directory were generated
 with `schemagen`, you can look at [samples/CMakeLists.txt](samples/CMakeLists.txt) for a few examples of how to call it:

src/CMakeLists.txt

@@ -51,6 +51,12 @@ if(GRAPHQL_BUILD_SCHEMAGEN)
   set(BOOST_COMPONENTS program_options)
   set(BOOST_LIBRARIES Boost::program_options)
 
+  if(NOT MSVC)
+    set(BOOST_COMPONENTS ${BOOST_COMPONENTS} filesystem)
+    set(BOOST_LIBRARIES ${BOOST_LIBRARIES} Boost::filesystem)
+    target_compile_options(schemagen PRIVATE -DUSE_BOOST_FILESYSTEM)
+  endif()
+  
   find_package(Boost REQUIRED COMPONENTS ${BOOST_COMPONENTS})
   target_link_libraries(schemagen PRIVATE ${BOOST_LIBRARIES})
 

src/SchemaGenerator.cpp

@@ -5,8 +5,15 @@
 
 #include <boost/program_options.hpp>
 
-#include <cctype>
+#ifdef USE_BOOST_FILESYSTEM
+#include <boost/filesystem.hpp>
+namespace fs = boost::filesystem;
+#else
 #include <filesystem>
+namespace fs = std::filesystem;
+#endif
+
+#include <cctype>
 #include <fstream>
 #include <iostream>
 #include <regex>
@@ -297,11 +304,11 @@ std::string Generator::getHeaderDir() const noexcept
 {
 	if (_isIntrospection)
 	{
-		return (std::filesystem::path { "include" } / "graphqlservice").string();
+		return (fs::path { "include" } / "graphqlservice").string();
 	}
 	else if (_options.paths)
 	{
-		return std::filesystem::path { _options.paths->headerPath }.string();
+		return fs::path { _options.paths->headerPath }.string();
 	}
 	else
 	{
@@ -317,13 +324,13 @@ std::string Generator::getSourceDir() const noexcept
 	}
 	else
 	{
-		return std::filesystem::path(_options.paths->sourcePath).string();
+		return fs::path(_options.paths->sourcePath).string();
 	}
 }
 
 std::string Generator::getHeaderPath() const noexcept
 {
-	std::filesystem::path fullPath { _headerDir };
+	fs::path fullPath { _headerDir };
 
 	if (_isIntrospection)
 	{
@@ -341,7 +348,7 @@ std::string Generator::getObjectHeaderPath() const noexcept
 {
 	if (_options.separateFiles)
 	{
-		std::filesystem::path fullPath { _headerDir };
+		fs::path fullPath { _headerDir };
 
 		fullPath /= (_options.customSchema->filenamePrefix + "Objects.h");
 		return fullPath.string();
@@ -352,7 +359,7 @@ std::string Generator::getObjectHeaderPath() const noexcept
 
 std::string Generator::getSourcePath() const noexcept
 {
-	std::filesystem::path fullPath { _sourceDir };
+	fs::path fullPath { _sourceDir };
 
 	if (_isIntrospection)
 	{
@@ -1659,8 +1666,7 @@ std::string Generator::getOutputCppType(const OutputField& field) const noexcept
 bool Generator::outputHeader() const noexcept
 {
 	std::ofstream headerFile(_headerPath, std::ios_base::trunc);
-	IncludeGuardScope includeGuard { headerFile,
-		std::filesystem::path(_headerPath).filename().string() };
+	IncludeGuardScope includeGuard { headerFile, fs::path(_headerPath).filename().string() };
 
 	headerFile << R"cpp(#include "graphqlservice/GraphQLService.h"
 
@@ -2042,8 +2048,8 @@ bool Generator::outputSource() const noexcept
 )cpp";
 	if (!_isIntrospection)
 	{
-		sourceFile << R"cpp(#include ")cpp"
-				   << std::filesystem::path(_objectHeaderPath).filename().string() << R"cpp("
+		sourceFile << R"cpp(#include ")cpp" << fs::path(_objectHeaderPath).filename().string()
+				   << R"cpp("
 
 )cpp";
 	}
@@ -3421,8 +3427,8 @@ std::string Generator::getIntrospectionType(
 std::vector<std::string> Generator::outputSeparateFiles() const noexcept
 {
 	std::vector<std::string> files;
-	const std::filesystem::path headerDir(_headerDir);
-	const std::filesystem::path sourceDir(_sourceDir);
+	const fs::path headerDir(_headerDir);
+	const fs::path sourceDir(_sourceDir);
 	std::string queryType;
 
 	for (const auto& operation : _operationTypes)
@@ -3437,10 +3443,10 @@ std::vector<std::string> Generator::outputSeparateFiles() const noexcept
 	// Output a convenience header
 	std::ofstream objectHeaderFile(_objectHeaderPath, std::ios_base::trunc);
 	IncludeGuardScope includeGuard { objectHeaderFile,
-		std::filesystem::path(_objectHeaderPath).filename().string() };
+		fs::path(_objectHeaderPath).filename().string() };
 
-	objectHeaderFile << R"cpp(#include ")cpp"
-					 << std::filesystem::path(_headerPath).filename().string() << R"cpp("
+	objectHeaderFile << R"cpp(#include ")cpp" << fs::path(_headerPath).filename().string()
+					 << R"cpp("
 
 )cpp";
 
@@ -3474,8 +3480,7 @@ std::vector<std::string> Generator::outputSeparateFiles() const noexcept
 		std::ofstream headerFile(headerPath, std::ios_base::trunc);
 		IncludeGuardScope includeGuard { headerFile, headerFilename };
 
-		headerFile << R"cpp(#include ")cpp"
-				   << std::filesystem::path(_headerPath).filename().string() << R"cpp("
+		headerFile << R"cpp(#include ")cpp" << fs::path(_headerPath).filename().string() << R"cpp("
 
 )cpp";
 
@@ -3498,7 +3503,7 @@ std::vector<std::string> Generator::outputSeparateFiles() const noexcept
 		sourceFile << R"cpp(// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
 
-#include ")cpp" << std::filesystem::path(_objectHeaderPath).filename().string()
+#include ")cpp" << fs::path(_objectHeaderPath).filename().string()
 				   << R"cpp("
 
 #include "graphqlservice/Introspection.h"