interpreter: do not use pathlib for DependencyVariableString creation

Path.is_dir() can raise a PermissionError if a parent does not have
the executable permission set; plus the "in p.parents" tests are
very expensive.  Do not use Path at all.

Signed-off-by: Paolo Bonzini <[email protected]>

Author: bonzini

mesonbuild/interpreter/interpreter.py

@@ -704,20 +704,18 @@ def func_declare_dependency(self, node: mparser.BaseNode, args: T.List[TYPE_var]
             version = self.project_version
         d_module_versions = kwargs['d_module_versions']
         d_import_dirs = self.extract_incdirs(kwargs, 'd_import_dirs')
-        srcdir = Path(self.environment.source_dir)
+        srcdir = self.environment.source_dir
+        subproject_dir = os.path.abspath(os.path.join(srcdir, self.subproject_dir))
+        project_root = os.path.abspath(os.path.join(srcdir, self.root_subdir))
         # convert variables which refer to an -uninstalled.pc style datadir
         for k, v in variables.items():
             if not v:
                 FeatureNew.single_use('empty variable value in declare_dependency', '1.4.0', self.subproject, location=node)
-            try:
-                p = Path(v)
-            except ValueError:
-                continue
-            else:
-                if not self.is_subproject() and srcdir / self.subproject_dir in p.parents:
-                    continue
-                if p.is_absolute() and p.is_dir() and srcdir / self.root_subdir in [p] + list(Path(os.path.abspath(p)).parents):
-                    variables[k] = P_OBJ.DependencyVariableString(v)
+            if os.path.isabs(v) \
+                    and (self.is_subproject() or not is_parent_path(subproject_dir, v)) \
+                    and is_parent_path(project_root, v) \
+                    and os.path.isdir(v):
+                variables[k] = P_OBJ.DependencyVariableString(v)
 
         dep = dependencies.InternalDependency(version, incs, compile_args,
                                               link_args, libs, libs_whole, sources, extra_files,

test cases/unit/125 declare_dep var/meson.build

@@ -0,0 +1,7 @@
+project('foo')
+
+declare_dependency(
+  variables: {
+    'dir': get_option('dir')
+  }
+)

test cases/unit/125 declare_dep var/meson_options.txt

@@ -0,0 +1 @@
+option('dir', type: 'string')

unittests/linuxliketests.py

@@ -1862,6 +1862,18 @@ def test_top_options_in_sp(self):
         testdir = os.path.join(self.unit_test_dir, '125 pkgsubproj')
         self.init(testdir)
 
+    def test_unreadable_dir_in_declare_dep(self):
+        testdir = os.path.join(self.unit_test_dir, '125 declare_dep var')
+        tmpdir = Path(tempfile.mkdtemp())
+        self.addCleanup(windows_proof_rmtree, tmpdir)
+        declaredepdir = tmpdir / 'test'
+        declaredepdir.mkdir()
+        try:
+            tmpdir.chmod(0o444)
+            self.init(testdir, extra_args=f'-Ddir={declaredepdir}')
+        finally:
+            tmpdir.chmod(0o755)
+
     def check_has_flag(self, compdb, src, argument):
         for i in compdb:
             if src in i['file']: