BadDependency: catch := slot operator in PDEPEND

Resolves: #693
Signed-off-by: Arthur Zamarin <arthurzam@gentoo.org>

src/pkgcheck/checks/metadata.py

@@ -942,10 +942,15 @@ def feed(self, pkg):
                         if all(map(self.deprecated, pkgs)):
                             deprecated[attr].add(atom)
 
-                    if in_or_restriction and atom.slot_operator == "=":
-                        yield BadDependency(
-                            attr, atom, "= slot operator used inside || block", pkg=pkg
-                        )
+                    if atom.slot_operator == "=":
+                        if in_or_restriction:
+                            yield BadDependency(
+                                attr, atom, "= slot operator used inside || block", pkg=pkg
+                            )
+                        elif attr == "pdepend" and not atom.blocks:
+                            # prohibited by PMS at the "Slot dependencies" section
+                            msg = "':=' operator is invalid in"
+                            yield BadDependency(attr, atom, msg, pkg=pkg)
 
                     if pkg.eapi.options.has_use_dep_defaults and atom.use is not None:
                         missing_use_deps = self._check_use_deps(attr, atom)

tests/checks/test_metadata.py

@@ -928,6 +928,13 @@ def test_depset(self, attr):
         assert "= slot operator used in blocker" in str(r)
         assert f'{attr.upper()}="!dev-libs/foo:="' in str(r)
 
+        if attr == "PDEPEND":
+            # check for := in PDEPEND
+            r = self.assertReport(chk, mk_pkg(eapi="5", depset="dev-libs/foo:="))
+            assert isinstance(r, metadata.BadDependency)
+            assert "':=' operator" in str(r)
+            assert f'{attr.upper()}="dev-libs/foo:="' in str(r)
+
         # check for missing package revisions
         self.assertNoReport(chk, mk_pkg("=dev-libs/foo-1-r0"))
         r = self.assertReport(chk, mk_pkg(eapi="6", depset="=dev-libs/foo-1"))