intepreter: Move remaining PCH validation to Interpreter

Author: dcbaker

mesonbuild/build.py

@@ -1591,12 +1591,8 @@ def check_can_link_together(self, t: BuildTargetTypes) -> None:
                 mlog.warning(msg + ' This will fail in cross build.')
 
     def add_pch(self, language: str, pchlist: T.List[str]) -> None:
-        if not pchlist:
-            return
-        for f in pchlist:
-            if not os.path.isfile(os.path.join(self.environment.source_dir, self.subdir, f)):
-                raise MesonException(f'File {f} does not exist.')
-        self.pch[language] = pchlist
+        if pchlist:
+            self.pch[language] = pchlist
 
     def add_include_dirs(self, args: T.Sequence['IncludeDirs'], set_is_system: T.Optional[str] = None) -> None:
         ids: T.List['IncludeDirs'] = []

mesonbuild/interpreter/interpreter.py

@@ -109,6 +109,7 @@
 import textwrap
 import importlib
 import copy
+import itertools
 
 if T.TYPE_CHECKING:
     from typing_extensions import Literal
@@ -3477,6 +3478,13 @@ def build_target(self, node: mparser.BaseNode, args: T.Tuple[str, SourcesVarargs
         if targetclass is not build.Jar:
             self.check_for_jar_sources(sources, targetclass)
             kwargs['d_import_dirs'] = self.extract_incdirs(kwargs, 'd_import_dirs')
+            missing: T.List[str] = []
+            for each in itertools.chain(kwargs['c_pch'], kwargs['cpp_pch']):
+                if each is not None:
+                    if not os.path.isfile(os.path.join(self.environment.source_dir, self.subdir, each)):
+                        missing.append(os.path.join(self.subdir, each))
+            if missing:
+                raise InvalidArguments('The following PCH files do not exist: {}'.format(', '.join(missing)))
 
         # Filter out kwargs from other target types. For example 'soversion'
         # passed to library() when default_library == 'static'.

test cases/failing/86 missing pch file/test.json

@@ -2,7 +2,7 @@
   "stdout": [
     {
       "comment": "literal 'pch/prog.h' from meson.build appears in output, irrespective of os.path.sep",
-      "line": "test cases/failing/86 missing pch file/meson.build:2:6: ERROR: File pch/prog.h does not exist."
+      "line": "test cases/failing/86 missing pch file/meson.build:2:6: ERROR: The following PCH files do not exist: pch/prog.h, pch/prog_pch.c"
     }
   ]
 }