Simplify native CMake generator

After the previous refactoring of Corrosion CMake code, we can now reuse
a significant portion of logic and greatly simplify
the Rust application that generates some CMake code.

We still need it for legacy CMake versions to parse JSON, but a lot of
functionality was already implemented in CMake.

This commit removes this code duplication.

cmake/Corrosion.cmake

@@ -769,6 +769,8 @@ function(corrosion_import_crate)
         set(COR_MANIFEST_PATH ${CMAKE_CURRENT_SOURCE_DIR}/${COR_MANIFEST_PATH})
     endif()
 
+    _corrosion_parse_platform(${COR_MANIFEST_PATH} ${Rust_VERSION} ${_CORROSION_RUST_CARGO_TARGET})
+
     if (CORROSION_NATIVE_TOOLING)
         execute_process(
             COMMAND
@@ -795,27 +797,6 @@ function(corrosion_import_crate)
             set (_CORROSION_CONFIGURATION_ROOT --configuration-root ${CMAKE_VS_PLATFORM_NAME})
         endif()
 
-        if (_CORROSION_RUST_CARGO_TARGET)
-            set(_CORROSION_TARGET --target ${_CORROSION_RUST_CARGO_TARGET})
-        endif()
-
-        if(CMAKE_CONFIGURATION_TYPES)
-            string (REPLACE ";" "," _CONFIGURATION_TYPES
-                "${CMAKE_CONFIGURATION_TYPES}")
-            set (_CORROSION_CONFIGURATION_TYPES --configuration-types
-                ${_CONFIGURATION_TYPES})
-        elseif(CMAKE_BUILD_TYPE)
-            set (_CORROSION_CONFIGURATION_TYPES --configuration-type
-                ${CMAKE_BUILD_TYPE})
-        else()
-            # uses default build type
-        endif()
-
-        set(no_default_libs_arg)
-        if(COR_NO_STD)
-            set(no_default_libs_arg "--no-default-libraries")
-        endif()
-
         set(crates_args)
         foreach(crate ${COR_CRATES})
             list(APPEND crates_args --crates ${crate})
@@ -827,12 +808,8 @@ function(corrosion_import_crate)
                     --manifest-path ${COR_MANIFEST_PATH}
                     gen-cmake
                         ${_CORROSION_CONFIGURATION_ROOT}
-                        ${_CORROSION_TARGET}
-                        ${_CORROSION_CONFIGURATION_TYPES}
                         ${crates_args}
                         ${cargo_profile}
-                        ${no_default_libs_arg}
-                        --cargo-version ${_CORROSION_CARGO_VERSION}
                         -o ${generated_cmake}
             WORKING_DIRECTORY ${CMAKE_BINARY_DIR}
             RESULT_VARIABLE ret)
@@ -846,10 +823,6 @@ function(corrosion_import_crate)
         _generator_add_cargo_targets(
             MANIFEST_PATH
                 "${COR_MANIFEST_PATH}"
-            TARGET
-                "${_CORROSION_RUST_CARGO_TARGET}"
-            RUST_VERSION
-                "${Rust_VERSION}"
             CRATES
                 "${COR_CRATES}"
             PROFILE

cmake/CorrosionGenerator.cmake

@@ -104,7 +104,7 @@ endfunction()
 
 function(_generator_add_cargo_targets)
     set(options "")
-    set(one_value_args MANIFEST_PATH TARGET RUST_VERSION PROFILE)
+    set(one_value_args MANIFEST_PATH PROFILE)
     set(multi_value_args CRATES)
     cmake_parse_arguments(
         GGC
@@ -124,8 +124,6 @@ function(_generator_add_cargo_targets)
     string(JSON ws_mems_len LENGTH ${workspace_members})
     math(EXPR ws_mems_len-1 "${ws_mems_len} - 1")
 
-    _corrosion_parse_platform(${GGC_MANIFEST_PATH} ${GGC_RUST_VERSION} ${GGC_TARGET})
-
     set(created_targets "")
     foreach(ix RANGE ${pkgs_len-1})
         string(JSON pkg GET "${packages}" ${ix})

generator/Cargo.toml

@@ -7,8 +7,6 @@ edition = "2018"
 
 [dependencies]
 cargo_metadata = "0.14"
-semver = "1.0"
-platforms = "2.0"
 
 [dependencies.clap]
 version = "2.34"