implement @PLAINNAME0@ and @BASENAME0@

@PLAINNAME@ and @BASENAME@ cannot be used in custom_target()
with multiple inputs. For those, similar macros are needed
with an index.

Fixes #13164

2 files changed, 13 insertions, 2 deletions

diff --git a/mesonbuild/interpreter/interpreter.py b/mesonbuild/interpreter/interpreter.py
index f6b4cf4..08bd054 100644
--- a/mesonbuild/interpreter/interpreter.py
+++ b/mesonbuild/interpreter/interpreter.py
@@ -1983,17 +1983,23 @@ class Interpreter(InterpreterBase, HoldableObject):
     def func_subdir_done(self, node: mparser.BaseNode, args: TYPE_var, kwargs: TYPE_kwargs) -> T.NoReturn:
         raise SubdirDoneRequest()
 
-    @staticmethod
-    def _validate_custom_target_outputs(has_multi_in: bool, outputs: T.Iterable[str], name: str) -> None:
+    def _validate_custom_target_outputs(self, has_multi_in: bool, outputs: T.Iterable[str], name: str) -> None:
         """Checks for additional invalid values in a custom_target output.
 
         This cannot be done with typed_kwargs because it requires the number of
         inputs.
         """
+        inregex: T.List[str] = ['@PLAINNAME[0-9]+@', '@BASENAME[0-9]+@']
+        from ..utils.universal import iter_regexin_iter
         for out in outputs:
+            match = iter_regexin_iter(inregex, [out])
             if has_multi_in and ('@PLAINNAME@' in out or '@BASENAME@' in out):
                 raise InvalidArguments(f'{name}: output cannot contain "@PLAINNAME@" or "@BASENAME@" '
                                        'when there is more than one input (we can\'t know which to use)')
+            elif match:
+                FeatureNew.single_use(
+                    f'{match} in output', '1.5.0',
+                    self.subproject)
 
     @typed_pos_args('custom_target', optargs=[str])
     @typed_kwargs(
diff --git a/mesonbuild/utils/universal.py b/mesonbuild/utils/universal.py
index ce9afd9..c831169 100644
--- a/mesonbuild/utils/universal.py
+++ b/mesonbuild/utils/universal.py
@@ -1744,6 +1744,8 @@ def get_filenames_templates_dict(inputs: T.List[str], outputs: T.List[str]) -> T
     If there is more than one input file, the following keys are also created:
 
     @INPUT0@, @INPUT1@, ... one for each input file
+    @PLAINNAME0@, @PLAINNAME1@, ... one for each input file
+    @BASENAME0@, @BASENAME1@, ... one for each input file
 
     If there is more than one output file, the following keys are also created:
 
@@ -1757,6 +1759,9 @@ def get_filenames_templates_dict(inputs: T.List[str], outputs: T.List[str]) -> T
         for (ii, vv) in enumerate(inputs):
             # Write out @INPUT0@, @INPUT1@, ...
             values[f'@INPUT{ii}@'] = vv
+            plain = os.path.basename(vv)
+            values[f'@PLAINNAME{ii}@'] = plain
+            values[f'@BASENAME{ii}@'] = os.path.splitext(plain)[0]
         if len(inputs) == 1:
             # Just one value, substitute @PLAINNAME@ and @BASENAME@
             values['@PLAINNAME@'] = plain = os.path.basename(inputs[0])