Add to_list() method to include_directories objects

clean up

fix tests for windows paths mimicing what was done in other unit tests (e.g., test case 74)

Update mesonbuild/interpreter/interpreterobjects.py

Co-authored-by: Charles Brunet <charles.brunet@optelgroup.com>

Update docs/markdown/snippets/include_directories_to_list.md

Co-authored-by: Charles Brunet <charles.brunet@optelgroup.com>

Update mesonbuild/interpreter/interpreterobjects.py

Co-authored-by: Charles Brunet <charles.brunet@optelgroup.com>

Update docs/yaml/objects/inc.yaml

Co-authored-by: Charles Brunet <charles.brunet@optelgroup.com>

Fix comment language

docs/markdown/snippets/include_directories_to_list.md

@@ -0,0 +1,10 @@
+## include_directories object now have a to_list() method
+
+The [[@inc]] object returned by [[include_directories]] now has a `to_list()` method that
+returns a list of strings of absolute paths. Unless the include path is a 
+system path, there will be a path for the source root and one for the build root.
+
+```
+inc = include_directories('include')
+include_paths = inc.to_list()
+```

docs/yaml/objects/inc.yaml

@@ -1,3 +1,13 @@
 name: inc
 long_name: Include directories
 description: Opaque wrapper for storing include directories
+
+methods:
+- name: to_list
+  returns: list[str]
+  since: 1.12.0
+  description: |
+    Returns a list of strings of absolute paths to the directories
+    contained within the object. Unless the path is a system path,
+    there will be a path relative to the source root and one
+    relative to the build root. System paths are provided as-is.

mesonbuild/interpreter/interpreterobjects.py

@@ -797,9 +797,15 @@ class MachineHolder(ObjectHolder['MachineInfo']):
             return self.held_object.subsystem
         raise InterpreterException('Subsystem not defined or could not be autodetected.')
 
-
 class IncludeDirsHolder(ObjectHolder[build.IncludeDirs]):
-    pass
+    @noPosargs
+    @noKwargs
+    @FeatureNew('inc.to_list', '1.12.0')
+    @InterpreterObject.method('to_list')
+    def to_list_method(self, args: T.List[TYPE_var], kwargs: TYPE_kwargs) -> T.List[str]:
+        if self.held_object.is_system:
+            return self.held_object.incdirs
+        return self.held_object.abs_string_list(self.env.source_dir, self.env.build_dir)
 
 class FileHolder(ObjectHolder[mesonlib.File]):
     def __init__(self, file: mesonlib.File, interpreter: 'Interpreter'):

test cases/common/18 includedir/meson.build

@@ -30,3 +30,11 @@ testcase expect_error(errormsg)
 endtestcase
 # Test for issue #12217
 include_directories(meson.current_source_dir() + 'xyz')
+
+# Test to see if an include_directory object will have the subdirectory in the path
+source_dir = meson.current_source_dir() / 'src'
+build_dir = meson.current_build_dir() / 'src'
+expected = [source_dir / '.', build_dir / '.']
+# Use fs.as_posix() to ensure the results are the same across platforms.
+fs = import('fs')
+assert(fs.as_posix('@0@'.format(subdir_inc.to_list())) == '@0@'.format(expected))

test cases/common/18 includedir/src/meson.build

@@ -3,3 +3,5 @@ test('inc test', exe)
 
 exe2 = executable('prog2', 'prog.c', 'func.c', include_directories : [['../include']])
 test('inc test 2', exe2)
+
+subdir_inc = include_directories('.')

test cases/common/218 include_dir dot/meson.build

@@ -5,4 +5,4 @@ project('Include Here', 'c')
 
 inc = include_directories('.')
 
-subdir('src')
+subdir('src')

test cases/common/218 include_dir dot/src/meson.build

@@ -1,6 +1,15 @@
+# test to_list() for include_directories defined in the parent meson.build file
+source_dir = meson.project_source_root()
+build_dir = meson.project_build_root()
+expected = [source_dir / '.', build_dir / '.']
+# Use fs.as_posix() to ensure the results are the same across platforms.
+fs = import('fs')
+assert(fs.as_posix('@0@'.format(inc.to_list())) == '@0@'.format(expected))
+
+# test include directories
 t = executable(
   'main',
   ['main.c', 'rone.c'],
   include_directories : inc,
   implicit_include_directories : false,
-)
+)

test cases/common/250 system include dir/meson.build

@@ -9,5 +9,9 @@ if not ['gcc', 'clang', 'clang-cl'].contains(compiler_id)
 endif
 
 lib_include_directories = include_directories('lib', is_system: true)
+
+# test that a system library include_directories just contains a single path
+assert('@0@'.format(lib_include_directories.to_list()) == '[\'lib\']')
+
 add_project_arguments('-Wsign-conversion', language: 'cpp')
-executable('system_include_dir_test', sources: 'main.cpp', include_directories: lib_include_directories)
+executable('system_include_dir_b_test', sources: 'main.cpp', include_directories: lib_include_directories)

test cases/common/74 file object/meson.build

@@ -7,8 +7,6 @@ test('fobj', executable('fobj', prog0, lib0))
 subdir('subdir1')
 subdir('subdir2')
 
-# Use fs.as_posix() because / operator replaces \ with / in the path, but
-# full_path() method is not doing that. This is a pretty inconsistent across all
-# Meson APIs.
+# Use fs.as_posix() to ensure the results are the same across platforms.
 fs = import('fs')
 assert(fs.as_posix(prog0[0].full_path()) == fs.as_posix(meson.current_source_dir() / 'prog.c'))