implement the new preserve_path kwarg for install_data too

Primarily interesting to me because it is then available for the python
module's install_sources method.

Based on the new feature in install_headers.

docs/markdown/snippets/install_sources_preserve_path_arg.md

@@ -0,0 +1,8 @@
+## Added preserve_path arg to install_data
+
+The [[install_data]] function now has an optional argument `preserve_path`
+that allows installing multi-directory data file structures that live
+alongside source code with a single command.
+
+This is also available in the specialized `py_installation.install_sources`
+method.

docs/yaml/functions/install_data.yaml

@@ -43,6 +43,15 @@ kwargs:
       to install only a subset of the files. By default these files have no install
       tag which means they are not being installed when `--tags` argument is specified.
 
+  preserve_path:
+    type: bool
+    since: 0.64.0
+    default: false
+    description: |
+      Disable stripping child-directories from data files when installing.
+
+      This is equivalent to GNU Automake's `nobase` option.
+
   rename:
     type: list[str]
     since: 0.46.0

mesonbuild/interpreter/interpreter.py

@@ -79,6 +79,7 @@ from .type_checking import (
     INSTALL_TAG_KW,
     LANGUAGE_KW,
     NATIVE_KW,
+    PRESERVE_PATH_KW,
     REQUIRED_KW,
     SOURCES_KW,
     VARIABLES_KW,
@@ -2094,7 +2095,7 @@ class Interpreter(InterpreterBase, HoldableObject):
     @typed_pos_args('install_headers', varargs=(str, mesonlib.File))
     @typed_kwargs(
         'install_headers',
-        KwargInfo('preserve_path', bool, default=False, since='0.63.0'),
+        PRESERVE_PATH_KW,
         KwargInfo('subdir', (str, NoneType)),
         INSTALL_MODE_KW.evolve(since='0.47.0'),
         INSTALL_DIR_KW,
@@ -2302,6 +2303,7 @@ class Interpreter(InterpreterBase, HoldableObject):
         INSTALL_MODE_KW.evolve(since='0.38.0'),
         INSTALL_TAG_KW.evolve(since='0.60.0'),
         INSTALL_DIR_KW,
+        PRESERVE_PATH_KW.evolve(since='0.64.0'),
     )
     def func_install_data(self, node: mparser.BaseNode,
                           args: T.Tuple[T.List['mesonlib.FileOrString']],
@@ -2321,19 +2323,35 @@ class Interpreter(InterpreterBase, HoldableObject):
         else:
             install_dir_name = '{datadir}'
         return self.install_data_impl(sources, kwargs['install_dir'], kwargs['install_mode'],
-                                      rename, kwargs['install_tag'], install_dir_name)
+                                      rename, kwargs['install_tag'], install_dir_name,
+                                      preserve_path=kwargs['preserve_path'])
 
     def install_data_impl(self, sources: T.List[mesonlib.File], install_dir: T.Optional[str],
                           install_mode: FileMode, rename: T.Optional[str],
                           tag: T.Optional[str],
                           install_dir_name: T.Optional[str] = None,
-                          install_data_type: T.Optional[str] = None) -> build.Data:
+                          install_data_type: T.Optional[str] = None,
+                          preserve_path: bool = False) -> build.Data:
 
         """Just the implementation with no validation."""
-        data = build.Data(sources, install_dir, install_dir_name or install_dir, install_mode,
-                          self.subproject, rename, tag, install_data_type)
-        self.build.data.append(data)
-        return data
+        idir = install_dir or ''
+        idir_name = install_dir_name or idir
+        dirs = collections.defaultdict(list)
+        ret_data = []
+        if preserve_path:
+            for file in sources:
+                dirname = os.path.dirname(file.fname)
+                dirs[dirname].append(file)
+        else:
+            dirs[''].extend(sources)
+
+        for childdir, files in dirs.items():
+            d = build.Data(files, os.path.join(idir, childdir), os.path.join(idir_name, childdir),
+                           install_mode, self.subproject, rename, tag, install_data_type)
+            ret_data.append(d)
+
+        self.build.data.extend(ret_data)
+        return ret_data
 
     @typed_pos_args('install_subdir', str)
     @typed_kwargs(

mesonbuild/interpreter/type_checking.py

@@ -438,3 +438,5 @@ VARIABLES_KW: KwargInfo[T.Dict[str, str]] = KwargInfo(
     convertor=variables_convertor,
     default={},
 )
+
+PRESERVE_PATH_KW: KwargInfo[bool] = KwargInfo('preserve_path', bool, default=False, since='0.63.0')

mesonbuild/modules/python.py

@@ -30,7 +30,7 @@ from ..dependencies.base import process_method_kw
 from ..dependencies.detect import get_dep_identifier
 from ..environment import detect_cpu_family
 from ..interpreter import ExternalProgramHolder, extract_required_kwarg, permitted_dependency_kwargs
-from ..interpreter.type_checking import NoneType
+from ..interpreter.type_checking import NoneType, PRESERVE_PATH_KW
 from ..interpreterbase import (
     noPosargs, noKwargs, permittedKwargs, ContainerTypeInfo,
     InvalidArguments, typed_pos_args, typed_kwargs, KwargInfo,
@@ -588,8 +588,13 @@ class PythonInstallation(ExternalProgramHolder):
             return dep
 
     @typed_pos_args('install_data', varargs=(str, mesonlib.File))
-    @typed_kwargs('python_installation.install_sources', _PURE_KW, _SUBDIR_KW,
-                  KwargInfo('install_tag', (str, NoneType), since='0.60.0'))
+    @typed_kwargs(
+        'python_installation.install_sources',
+        _PURE_KW,
+        _SUBDIR_KW,
+        PRESERVE_PATH_KW,
+        KwargInfo('install_tag', (str, NoneType), since='0.60.0')
+    )
     def install_sources_method(self, args: T.Tuple[T.List[T.Union[str, mesonlib.File]]],
                                kwargs: 'PyInstallKw') -> 'Data':
         tag = kwargs['install_tag'] or 'runtime'
@@ -597,7 +602,8 @@ class PythonInstallation(ExternalProgramHolder):
             self.interpreter.source_strings_to_files(args[0]),
             self._get_install_dir_impl(kwargs['pure'], kwargs['subdir']),
             mesonlib.FileMode(), rename=None, tag=tag, install_data_type='python',
-            install_dir_name=self._get_install_dir_name_impl(kwargs['pure'], kwargs['subdir']))
+            install_dir_name=self._get_install_dir_name_impl(kwargs['pure'], kwargs['subdir']),
+            preserve_path=kwargs['preserve_path'])
 
     @noPosargs
     @typed_kwargs('python_installation.install_dir', _PURE_KW, _SUBDIR_KW)

test cases/common/252 install data structured/meson.build

@@ -0,0 +1,16 @@
+project('install structured data')
+
+install_data(
+    'dir1/file1',
+    'dir1/file2',
+    'dir1/file3',
+    'dir2/file1',
+    'dir2/file2',
+    'dir2/file3',
+    'dir3/file1',
+    'dir3/file2',
+    'dir3/file3',
+    install_dir: get_option('datadir'),
+    preserve_path: true,
+)
+subdir('pysrc')

test cases/common/252 install data structured/pysrc/__init__.py

@@ -0,0 +1 @@
+'''init for mod'''

test cases/common/252 install data structured/pysrc/bad.py

@@ -0,0 +1 @@
+'''mod.bad should not be installed'''

test cases/common/252 install data structured/pysrc/bar.py

@@ -0,0 +1 @@
+'''mod.bar module'''

test cases/common/252 install data structured/pysrc/foo.py

@@ -0,0 +1 @@
+'''mod.foo module'''

test cases/common/252 install data structured/pysrc/meson.build

@@ -0,0 +1,11 @@
+py_inst = import('python').find_installation()
+
+py_inst.install_sources(
+    '__init__.py',
+    'foo.py',
+    'bar.py',
+    'submod/__init__.py',
+    'submod/baz.py',
+    subdir: 'mod',
+    preserve_path: true,
+)

test cases/common/252 install data structured/pysrc/submod/__init__.py

@@ -0,0 +1 @@
+'''init for submod'''

test cases/common/252 install data structured/pysrc/submod/bad.py

@@ -0,0 +1 @@
+'''mod.submod.bad should not be installed'''

test cases/common/252 install data structured/pysrc/submod/baz.py

@@ -0,0 +1 @@
+'''mod.submod.baz module'''

test cases/common/252 install data structured/test.json

@@ -0,0 +1,18 @@
+{
+  "installed": [
+    {"type": "python_file", "file": "usr/@PYTHON_PURELIB@/mod/__init__.py"},
+    {"type": "python_file", "file": "usr/@PYTHON_PURELIB@/mod/foo.py"},
+    {"type": "python_file", "file": "usr/@PYTHON_PURELIB@/mod/bar.py"},
+    {"type": "python_file", "file": "usr/@PYTHON_PURELIB@/mod/submod/__init__.py"},
+    {"type": "python_file", "file": "usr/@PYTHON_PURELIB@/mod/submod/baz.py"},
+    {"type": "file", "file": "usr/share/dir1/file1"},
+    {"type": "file", "file": "usr/share/dir1/file2"},
+    {"type": "file", "file": "usr/share/dir1/file3"},
+    {"type": "file", "file": "usr/share/dir2/file1"},
+    {"type": "file", "file": "usr/share/dir2/file2"},
+    {"type": "file", "file": "usr/share/dir2/file3"},
+    {"type": "file", "file": "usr/share/dir3/file1"},
+    {"type": "file", "file": "usr/share/dir3/file2"},
+    {"type": "file", "file": "usr/share/dir3/file3"}
+  ]
+}

test cases/python/7 install path/meson.build

@@ -8,3 +8,5 @@ project('install path',
 py = import('python').find_installation()
 py.install_sources('test.py')
 py.install_sources('test.py', pure: false)
+
+subdir('structured')

test cases/python/7 install path/structured/meson.build

@@ -0,0 +1,9 @@
+py.install_sources(
+  'one.py',
+  'two.py',
+  'alpha/one.py',
+  'alpha/two.py',
+  'alpha/three.py',
+  'beta/one.py',
+  preserve_path: true,
+)

test cases/python/7 install path/test.json

@@ -1,5 +1,11 @@
 {
   "installed": [
+    {"type": "file", "file": "pure/one.py"},
+    {"type": "file", "file": "pure/two.py"},
+    {"type": "file", "file": "pure/alpha/one.py"},
+    {"type": "file", "file": "pure/alpha/two.py"},
+    {"type": "file", "file": "pure/alpha/three.py"},
+    {"type": "file", "file": "pure/beta/one.py"},
     {"type": "file", "file": "plat/test.py"},
     {"type": "file", "file": "pure/test.py"}
   ]