platform: configure the libdir and datadir from the build system

Our build systems know what the libdir and datadir that will be used is,
and we should honor that.

CMakeLists.txt

@@ -6,6 +6,7 @@ project(
     LANGUAGES CXX
     VERSION ${VERSION_STRIPPED}
 )
+include(GNUInstallDirs)
 
 add_subdirectory(src)
 

meson.build

@@ -40,7 +40,7 @@ foreach t : [['cps integration tests', 'cps-config.toml'], ['pkg-config compatib
   test(
     t[0],
     python_interpreter,
-    args: [files('tests/runner.py'), cps_config, 'tests/cases/' + t[1]],
+    args: [files('tests/runner.py'), cps_config, 'tests/cases/' + t[1], '--libdir', get_option('libdir')],
     protocol : 'tap',
     env : {'CPS_PREFIX_PATH' : meson.current_source_dir() / 'tests' / 'cps-files' },
   )

src/cps/config.hpp.in

@@ -1,3 +1,5 @@
 #pragma once
 
 #define CPS_CONFIG_VERSION "${CMAKE_PROJECT_VERSION}"
+#define CPS_CONFIG_LIBDIR  "${CMAKE_INSTALL_LIBDIR}"
+#define CPS_CONFIG_DATADIR "${CMAKE_INSTALL_DATADIR}"

src/cps/meson.build

@@ -3,6 +3,8 @@
 
 conf = configuration_data()
 conf.set_quoted('CPS_CONFIG_VERSION', meson.project_version())
+conf.set_quoted('CPS_CONFIG_LIBDIR', get_option('libdir'))
+conf.set_quoted('CPS_CONFIG_DATADIR', get_option('datadir'))
 
 conf_h = configure_file(
   configuration : conf,

src/cps/platform.cpp

@@ -2,11 +2,12 @@
 // Copyright © 2024 Dylan Baker
 
 #include "cps/platform.hpp"
+#include "cps/config.hpp"
 
 namespace cps::platform {
 
-    fs::path libdir() { return "lib"; }
+    fs::path libdir() { return CPS_CONFIG_LIBDIR; }
 
-    fs::path datadir() { return "share"; }
+    fs::path datadir() { return CPS_CONFIG_DATADIR; }
 
 } // namespace cps::platform

tests/CMakeLists.txt

@@ -32,6 +32,6 @@ foreach (test_name test_case IN ZIP_LISTS test_names test_cases)
         COMMAND
         ${CMAKE_COMMAND} -E env CPS_PREFIX_PATH=${CMAKE_CURRENT_SOURCE_DIR}/cps-files
         ${Python_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}/runner.py
-        $<TARGET_FILE:cps-config> ${test_case}
+        $<TARGET_FILE:cps-config> ${test_case} --libdir "${CMAKE_INSTALL_LIBDIR}"
     )
 endforeach ()

tests/runner.py

@@ -6,10 +6,13 @@
 
 import argparse
 import asyncio
+import contextlib
 import dataclasses
 import enum
 import os
+import shutil
 import sys
+import tempfile
 import tomllib
 import typing
 
@@ -19,6 +22,7 @@ class Arguments(typing.Protocol):
 
         runner: str
         cases: str
+        libdir: str
 
     class TestCase(typing.TypedDict):
 
@@ -99,15 +103,7 @@ async def test(runner: str, case_: TestCase) -> Result:
     return Result(case_['name'], result, out, err, returncode, expected, cmd)
 
 
-async def main() -> None:
-    parser = argparse.ArgumentParser()
-    parser.add_argument('runner', help="The compiled cps-config binary")
-    parser.add_argument('cases', help="A toml file containing case descriptions")
-    args: Arguments = parser.parse_args()
-
-    with open(os.path.join(SOURCE_DIR, args.cases), 'rb') as f:
-        tests = typing.cast('TestDescription', tomllib.load(f))
-
+async def run_tests(args: Arguments, tests: TestDescription) -> bool:
     print(f'1..{len(tests["case"])}')
 
     results = typing.cast(
@@ -129,8 +125,47 @@ async def main() -> None:
 
             encountered_failure = True
 
-    if encountered_failure:
-        exit(1)
+    return encountered_failure
+
+
+async def main() -> None:
+    parser = argparse.ArgumentParser()
+    parser.add_argument('runner', help="The compiled cps-config binary")
+    parser.add_argument('cases', help="A toml file containing case descriptions")
+    parser.add_argument('--libdir', default='lib', help="the build system configured libdir")
+    args: Arguments = parser.parse_args()
+
+    with open(os.path.join(SOURCE_DIR, args.cases), 'rb') as f:
+        tests = typing.cast('TestDescription', tomllib.load(f))
+
+    with contextlib.ExitStack() as stack:
+        # If the libdir is not "lib" (which tests assume), create a symlink to
+        # the expected libdir
+        if args.libdir != 'lib':
+            prefix = str(os.environ['CPS_PREFIX_PATH'])
+            tmpdir = tempfile.mkdtemp()
+            stack.callback(shutil.rmtree, tmpdir)
+            os.environ['CPS_PREFIX_PATH'] = tmpdir
+
+            # Handle libdir with multiple paths, like lib/x86_64-linux-gnu
+            root, libdir = os.path.split(args.libdir)
+            if root:
+                tmpdir = os.path.join(tmpdir, root)
+                os.makedirs(tmpdir, exist_ok=True)
+
+            source = os.path.join(prefix, 'lib')
+            dest = os.path.join(tmpdir, libdir)
+            os.symlink(source, dest)
+            stack.callback(os.unlink, dest)
+
+            # Also override the PREFIX, which is used to calculate @prefix@
+            global PREFIX
+            PREFIX = os.path.join(tmpdir, libdir)
+
+        failed = await run_tests(args, tests)
+
+    sys.exit(1 if failed else 0)
+
 
 if __name__ == "__main__":
     asyncio.run(main())