msetup: not-found subprojects do not have known options

If a subproject had its SubprojectHolder created, but was disabled, its options were not
parsed; therefore the subproject should not be checked for unknown options.

Fixes: #14969
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

6 files changed, 18 insertions, 3 deletions

diff --git a/mesonbuild/msetup.py b/mesonbuild/msetup.py
index 8d7dd0bbf..f1fa777d1 100644
--- a/mesonbuild/msetup.py
+++ b/mesonbuild/msetup.py
@@ -16,6 +16,7 @@ from .options import OptionKey
 if T.TYPE_CHECKING:
     from typing_extensions import Protocol
     from .coredata import SharedCMDOptions
+    from .interpreter import SubprojectHolder
 
     class CMDOptions(SharedCMDOptions, Protocol):
 
@@ -192,9 +193,9 @@ class MesonApp:
                                     'Some other Meson process is already using this build directory. Exiting.'):
             return self._generate(env, capture, vslite_ctx)
 
-    def check_unused_options(self, coredata: 'coredata.CoreData', cmd_line_options: T.Dict[OptionKey, str], all_subprojects: T.Mapping[str, object]) -> None:
+    def check_unused_options(self, coredata: 'coredata.CoreData', cmd_line_options: T.Dict[OptionKey, str], all_subprojects: T.Mapping[str, SubprojectHolder]) -> None:
         errlist: T.List[str] = []
-        known_subprojects = all_subprojects.keys()
+        known_subprojects = [name for name, obj in all_subprojects.items() if obj.found()]
         for opt in cmd_line_options:
             # Accept options that exist or could appear in subsequent reconfigurations,
             # including options for subprojects that were not used
diff --git a/test cases/common/42 subproject/meson.build b/test cases/common/42 subproject/meson.build
index bc24adbcc..be2d90f7c 100644
--- a/test cases/common/42 subproject/meson.build
+++ b/test cases/common/42 subproject/meson.build
@@ -8,6 +8,7 @@ project('subproj user', 'c',
 assert(meson.project_name() == 'subproj user', 'Incorrect project name')
 
 sub = subproject('sublib', version : '1.0.0')
+assert(sub.found())
 
 if meson.project_version() != '2.3.4'
   error('Incorrect master project version string:' + meson.project_version())
@@ -29,3 +30,6 @@ unknown_var = sub.get_variable('does-not-exist', [])
 if unknown_var != []
   error ('unexpected fallback value for subproject.get_variable()')
 endif
+
+unusedsub = subproject('subunused', required: get_option('disabled_feature'))
+assert(not unusedsub.found())
diff --git a/test cases/common/42 subproject/meson.options b/test cases/common/42 subproject/meson.options
new file mode 100644
index 000000000..ae9a39fb1
--- /dev/null
+++ b/test cases/common/42 subproject/meson.options
@@ -0,0 +1 @@
+option('disabled_feature', type: 'feature', value: 'disabled')
diff --git a/test cases/common/42 subproject/subprojects/subunused/meson.build b/test cases/common/42 subproject/subprojects/subunused/meson.build
new file mode 100644
index 000000000..a42fed38b
--- /dev/null
+++ b/test cases/common/42 subproject/subprojects/subunused/meson.build
@@ -0,0 +1 @@
+syntax error because the subproject is unused
diff --git a/test cases/common/42 subproject/subprojects/subunused/meson.options b/test cases/common/42 subproject/subprojects/subunused/meson.options
new file mode 100644
index 000000000..a42fed38b
--- /dev/null
+++ b/test cases/common/42 subproject/subprojects/subunused/meson.options
@@ -0,0 +1 @@
+syntax error because the subproject is unused
diff --git a/test cases/common/42 subproject/test.json b/test cases/common/42 subproject/test.json
index e469052f4..7400ff4a0 100644
--- a/test cases/common/42 subproject/test.json
+++ b/test cases/common/42 subproject/test.json
@@ -7,5 +7,12 @@
     {"type": "file", "file": "usr/share/sublib/COPYING"},
     {"type": "file", "file": "usr/share/sublib/subprojects/sublib/sublicense1.txt"},
     {"type": "file", "file": "usr/share/sublib/subprojects/sublib/sublicense2.txt"}
-  ]
+  ],
+  "matrix": {
+    "options": {
+      "subunused:opt1": [
+	{ "val": "42" }
+      ]
+    }
+  }
 }