diff --git a/docs/development/index.md b/docs/development/index.md index d1c167f..cfd5893 100644 --- a/docs/development/index.md +++ b/docs/development/index.md @@ -176,6 +176,59 @@ not, MVT skips the module with a warning. They are the same records it writes to `.json`. Typed results per module are planned. +### Replacing a built-in module + +A custom module which extends a built-in one runs alongside it, and when the +two share a slug they write to the same results file. MVT warns about that +collision, naming both modules, where each came from and the file the later one +overwrites, but it runs them both. Set `replaces` to the class the module +supersedes to take that module's place instead: when both are available to a +command, the named module is dropped from the run. + +```python +from mvt.ios.modules.backup import Manifest as BuiltinManifest + + +class Manifest(BuiltinManifest): + supported_commands = (("ios", "check-backup"),) + replaces = BuiltinManifest +``` + +Keeping the class name of the replaced module, as above, keeps the name +`--module` selects the module by and the slug its results file is named after. +A replacement with a different class name writes to a file named after its own +slug, unless it sets `slug` to the slug of the module it replaces, and +`--module` still selects it by the name of the replaced module, which MVT logs. +Taking over the slug of a replaced module is not a collision and is not warned +about, because that module is no longer part of the run. + +Modules which depend on the replaced module receive the replacement instead, so +`get_dependency_results(BuiltinManifest)` returns the replacement's results. A +module must not depend on the module it replaces: that module does not run, so +the replacement has to produce the data itself, and MVT logs a warning when a +module declares both. + +A replacement takes on the obligations of the module it replaces. If it +declares a dependency the command does not provide, it is skipped like any +other module with an unavailable dependency, and the module it replaced stays +out of the run: neither of them produces results, and the modules depending on +the replaced module are skipped as well. + +Subclassing the replaced module is not required, but a replacement which is not +a subclass is logged with a warning, because its results may not be what the +modules depending on the replaced module expect. Naming a module the command +does not run has no effect, and modules which replace each other in a cycle all +keep running and replace nothing. Every applied substitution is logged, so it +is recorded in `command.log` when the command runs with an `--output` folder. + +Every command resolves replacements on its own. `check-iocs` matches stored +results files against the slugs of the modules available for that command, so a +replacement checks the indicators of its own results only if it also declares +the `("ios", "check-iocs")` pair; otherwise the built-in module it replaced +re-checks the file. It also matches `--module` on the class name only, so pass +a differently named replacement's own name there, not the name of the module +it replaces. + ### Importing from MVT Import from `mvt.plugin` if it has what you need. The names it exports are diff --git a/src/mvt/common/command.py b/src/mvt/common/command.py index f2f211d..1242941 100644 --- a/src/mvt/common/command.py +++ b/src/mvt/common/command.py @@ -72,6 +72,10 @@ class Command: # down a password to decrypt a backup or flags which are need by some modules. self.module_options = module_options if module_options else {} + # This dictionary maps the modules which were replaced by a module + # declaring `replaces` to the module which took their place. + self.module_replacements: dict[type[MVTModule], type[MVTModule]] = {} + # This list will contain all executed modules. # We can use this to reference e.g. self.executed[0].results. self.executed: list[MVTModule] = [] @@ -257,7 +261,174 @@ class Command: if module not in deduplicated: deduplicated.append(module) - return deduplicated + available = self._apply_replacements(deduplicated) + self._warn_about_slug_collisions(available) + + return available + + def _warn_about_slug_collisions(self, modules: list[type[MVTModule]]) -> None: + """Report modules writing their results to the same file. + + Results are stored in a file named after the module slug, so two + modules sharing one silently overwrite each other. Replacements are + already resolved here, so a module deliberately taking over the slug + of the module it replaces is not reported: the module it replaced is + no longer part of the run. + """ + modules_by_slug: dict[str, type[MVTModule]] = {} + for module in modules: + slug = module.get_slug() + first = modules_by_slug.setdefault(slug, module) + if first is module: + continue + + self.log.warning( + "Modules %s from %s and %s from %s both use the slug %s. If " + "both run, whichever runs last overwrites the results of the " + "other in %s.json.", + first.__name__, + get_module_origin(first).label, + module.__name__, + get_module_origin(module).label, + slug, + slug, + ) + + def _declared_replacements( + self, modules: list[type[MVTModule]] + ) -> dict[type[MVTModule], type[MVTModule]]: + """Return the replacements declared by the given modules.""" + replacements: dict[type[MVTModule], type[MVTModule]] = {} + for module in modules: + replaced = module.replaces + if replaced is None or replaced is module: + continue + + if not module.enabled: + # Replacing a module must not disable it, as a disabled + # replacement never runs in its place. + self.log.debug( + "Module %s is disabled and does not replace module %s.", + module.__name__, + replaced.__name__, + ) + continue + + if replaced not in modules: + # A module can support several commands while the module it + # replaces is only available in some of them. + self.log.debug( + "Module %s replaces module %s, which is not available " + "for the %s command.", + module.__name__, + replaced.__name__, + self.name, + ) + continue + + if replaced in replacements: + self.log.warning( + "Modules %s and %s both replace module %s. Both of them " + "will run, %s will not, and modules depending on %s will " + "use the results of %s. Replacements which share the slug " + "of %s overwrite each other's results file.", + replacements[replaced].__name__, + module.__name__, + replaced.__name__, + replaced.__name__, + replaced.__name__, + replacements[replaced].__name__, + replaced.__name__, + ) + continue + + replacements[replaced] = module + + return replacements + + def _drop_replacement_cycles( + self, replacements: dict[type[MVTModule], type[MVTModule]] + ) -> None: + """Undo the replacements between modules which replace each other.""" + cyclic: set[type[MVTModule]] = set() + for replaced in replacements: + walked: list[type[MVTModule]] = [] + module = replaced + while module in replacements and module not in cyclic: + if module in walked: + cyclic.update(walked[walked.index(module) :]) + break + walked.append(module) + module = replacements[module] + + if not cyclic: + return + + self.log.warning( + "Modules %s replace each other in a cycle. None of them replaces " + "anything and all of them will run.", + ", ".join(sorted(module.__name__ for module in cyclic)), + ) + for module in cyclic: + replacements.pop(module, None) + + def _log_replacement( + self, + replaced: type[MVTModule], + module: type[MVTModule], + replacement: type[MVTModule], + ) -> None: + """Report an applied replacement, and any problem with it.""" + if not issubclass(module, replaced): + self.log.warning( + "Module %s replaces module %s but is not a subclass of it. " + "Its results might not be compatible with what modules " + "depending on %s expect.", + module.__name__, + replaced.__name__, + replaced.__name__, + ) + + if replaced in module.dependencies: + self.log.warning( + "Module %s depends on module %s, which it also replaces. The " + "dependency cannot be satisfied: a replacement has to produce " + "that data itself.", + module.__name__, + replaced.__name__, + ) + + self.log.info( + "Module %s from %s replaces module %s from %s.", + replacement.__name__, + get_module_origin(replacement).label, + replaced.__name__, + get_module_origin(replaced).label, + ) + + def _apply_replacements( + self, modules: list[type[MVTModule]] + ) -> list[type[MVTModule]]: + """Drop the modules superseded by a module declaring `replaces`.""" + declared = self._declared_replacements(modules) + self._drop_replacement_cycles(declared) + + replacements: dict[type[MVTModule], type[MVTModule]] = {} + for replaced, module in declared.items(): + # Follow chains of replacements, so that a dependency on a + # replaced module always resolves to a module which is part of + # the run. + replacement = module + while replacement in declared: + replacement = declared[replacement] + + # Only the replacements which are applied are reported, so that + # the record matches the modules which actually run. + self._log_replacement(replaced, module, replacement) + replacements[replaced] = replacement + + self.module_replacements = replacements + return [module for module in modules if module not in replacements] def init(self) -> None: raise NotImplementedError @@ -317,6 +488,80 @@ class Command: console.print("") console.print(panel) + def _module_dependencies( + self, module: type[MVTModule] + ) -> list[tuple[type[MVTModule], type[MVTModule]]]: + """Return the (declared, resolved) dependencies of a module. + + A dependency on a module which was replaced is resolved to the module + which took its place. A module which replaces one of its own + dependencies is not made to depend on itself, while a module which + declares itself as a dependency is left alone and still fails the + circular dependency check. + """ + dependencies = [] + for dependency in module.dependencies: + resolved = self.module_replacements.get(dependency, dependency) + if resolved is module and dependency is not module: + continue + dependencies.append((dependency, resolved)) + + return dependencies + + @staticmethod + def _dependency_name( + declared: type[MVTModule], resolved: type[MVTModule] + ) -> str: + """Return how a dependency is named in the messages about it. + + A dependency is named as the module which declared it wrote it, and, + when that module was replaced, as the module which runs in its place. + """ + if declared is resolved: + return declared.__name__ + + return f"{resolved.__name__} (replacing module {declared.__name__})" + + def _selected_modules( + self, modules: list[type[MVTModule]] + ) -> Optional[list[type[MVTModule]]]: + """Return the modules explicitly requested, or all the enabled ones. + + Returns None when a module was requested by name and no module of + that name can be run. + """ + if not self.module_name: + return [module for module in modules if module.enabled] + + selected = [ + module for module in modules if module.__name__ == self.module_name + ] + + # A module replacing another one does not have to keep its name, so + # the name of a replaced module selects its replacement. + if not selected: + for replaced, replacement in self.module_replacements.items(): + if replaced.__name__ != self.module_name or replacement in selected: + continue + self.log.info( + "Module %s was replaced by module %s, which is run " + "in its place.", + replaced.__name__, + replacement.__name__, + ) + selected.append(replacement) + + if not selected: + self.log.warning( + "No module named %s is available for the %s command. " + "No modules will be run.", + self.module_name, + self.name, + ) + return None + + return selected + def _skipped_modules( self, required: list[type[MVTModule]], @@ -349,15 +594,18 @@ class Command: if module in skipped: continue - for dependency in module.dependencies: + for declared, dependency in self._module_dependencies(module): if dependency not in module_indexes: - skipped[module] = (module, dependency) + # A replaced dependency always resolves to a module of + # this command, so an unavailable one is always the + # module class the author declared. + skipped[module] = (module, declared) changed = True self.log.warning( "Module %s will be SKIPPED: it depends on module " "%s, which is not available in this command.%s", module.__name__, - dependency.__name__, + declared.__name__, remainder, ) break @@ -372,7 +620,7 @@ class Command: "module %s, itself skipped for depending on " "unavailable module %s.%s", module.__name__, - dependency.__name__, + self._dependency_name(declared, dependency), missing.__name__, remainder, ) @@ -383,7 +631,7 @@ class Command: "module %s, which depends on unavailable " "module %s.%s", module.__name__, - dependency.__name__, + self._dependency_name(declared, dependency), root.__name__, missing.__name__, remainder, @@ -397,12 +645,9 @@ class Command: modules = self._available_modules() module_indexes = {module: index for index, module in enumerate(modules)} - if self.module_name: - selected = [ - module for module in modules if module.__name__ == self.module_name - ] - else: - selected = [module for module in modules if module.enabled] + selected = self._selected_modules(modules) + if selected is None: + return None required: set[type[MVTModule]] = set() pending = list(selected) @@ -411,7 +656,7 @@ class Command: if module in required: continue required.add(module) - for dependency in module.dependencies: + for _, dependency in self._module_dependencies(module): # Unavailable dependencies are reported by _skipped_modules(). if dependency in module_indexes: pending.append(dependency) @@ -424,13 +669,14 @@ class Command: "Every selected module was skipped for an unavailable " "dependency. No modules will be run." ) + return None dependents: dict[type[MVTModule], list[type[MVTModule]]] = { module: [] for module in runnable } indegree = {module: 0 for module in runnable} for module in runnable: - for dependency in module.dependencies: + for _, dependency in self._module_dependencies(module): if dependency not in indegree: continue dependents[dependency].append(module) @@ -486,9 +732,12 @@ class Command: module_options=self.module_options, log=module_logger, ) + # Dependencies are keyed by the module class they declare, even + # when it was replaced, so that a module asking for the results + # of a replaced module receives those of its replacement. m.dependency_modules = { - dependency: executed_by_type[dependency] - for dependency in module.dependencies + dependency: executed_by_type[resolved] + for dependency, resolved in self._module_dependencies(module) } if self.iocs.total_ioc_count: diff --git a/src/mvt/common/module.py b/src/mvt/common/module.py index cd127a6..1257aa6 100644 --- a/src/mvt/common/module.py +++ b/src/mvt/common/module.py @@ -46,6 +46,11 @@ class MVTModule: slug: Optional[str] = None dependencies: Sequence[type["MVTModule"]] = () supported_commands: Sequence[tuple[str, str]] = () + # A custom module can name a module class it supersedes, usually a + # built-in one. When both are available to a command, the named module is + # dropped from the run and this module takes its place, including in the + # dependencies of any other module. + replaces: Optional[type["MVTModule"]] = None def __init__( self, diff --git a/tests/common/test_command.py b/tests/common/test_command.py index 4835fd3..8e09f57 100644 --- a/tests/common/test_command.py +++ b/tests/common/test_command.py @@ -68,6 +68,123 @@ class CustomDependsOnBuiltin(RecordingModule): dependencies = (FirstModule,) +class ReplacementModule(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + + def run(self): + super().run() + self.results = ["replacement"] + + +class OtherReplacementModule(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + + +class UnrelatedReplacementModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + replaces = IndependentModule + + +class ReplacementOfReplacementModule(ReplacementModule): + supported_commands = (("ios", "check-backup"),) + replaces = ReplacementModule + + def run(self): + super().run() + self.results = ["replacement of replacement"] + + +class ReplacesOwnDependencyModule(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + dependencies = (FirstModule,) + + +class DisabledReplacementModule(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + enabled = False + + +class MutualReplacementOne(RecordingModule): + supported_commands = (("ios", "check-backup"),) + + +class MutualReplacementTwo(RecordingModule): + supported_commands = (("ios", "check-backup"),) + replaces = MutualReplacementOne + + +MutualReplacementOne.replaces = MutualReplacementTwo + + +class CycleOneModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + + +class CycleTwoModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + replaces = CycleOneModule + + +class CycleThreeModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + replaces = CycleTwoModule + + +CycleOneModule.replaces = CycleThreeModule + + +class UnavailableDependencyModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + + +class ReplacementMissingDependency(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + dependencies = (UnavailableDependencyModule,) + + +class SharedSlugModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + slug = "shared_slug" + + +class OtherSharedSlugModule(RecordingModule): + supported_commands = (("ios", "check-backup"),) + slug = "shared_slug" + + +class ReplacementKeepingTheSlug(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + slug = "first_module" + + +class SameNameReplacementModule(FirstModule): + supported_commands = (("ios", "check-backup"),) + replaces = FirstModule + + def run(self): + super().run() + self.results = ["replacement"] + + +# Modules replacing a built-in one usually keep its class name, which is the +# name `--module` matches on. +SameNameReplacementModule.__name__ = "FirstModule" + + +def logged_substitutions(caplog) -> list[str]: + return [ + record.getMessage() + for record in caplog.records + if record.levelno == logging.INFO and "replaces module" in record.getMessage() + ] + + class RecordingCommand(Command): def init(self): self.initialized = True @@ -303,3 +420,376 @@ class TestCommand: cmd.run() assert RecordingModule.run_order == ["FirstModule", "CustomDependsOnBuiltin"] + + def test_custom_module_replaces_builtin(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule, IndependentModule] + cmd.custom_modules = [ReplacementModule] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == ["IndependentModule", "ReplacementModule"] + assert cmd.module_replacements == {FirstModule: ReplacementModule} + assert ( + "Module ReplacementModule from" in caplog.text + and "replaces module FirstModule" in caplog.text + ) + + def test_modules_without_replaces_all_run(self): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [CustomIOSBackupModule] + + cmd.run() + + assert RecordingModule.run_order == ["FirstModule", "CustomIOSBackupModule"] + assert cmd.module_replacements == {} + + def test_unavailable_replaced_module_is_ignored(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [IndependentModule] + cmd.custom_modules = [ReplacementModule] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == ["IndependentModule", "ReplacementModule"] + assert cmd.module_replacements == {} + assert "replaces module FirstModule" not in caplog.text + + def test_dependencies_are_resolved_to_the_replacement(self): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [SecondModule, FirstModule] + cmd.custom_modules = [ReplacementModule] + + cmd.run() + + assert RecordingModule.run_order == ["ReplacementModule", "SecondModule"] + second = next( + module for module in cmd.executed if isinstance(module, SecondModule) + ) + assert isinstance(second.dependency_modules[FirstModule], ReplacementModule) + assert second.results == ["replacement", "second"] + + def test_replacement_with_unavailable_dependency_skips_its_dependents( + self, caplog + ): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule, SecondModule, IndependentModule] + cmd.custom_modules = [ReplacementMissingDependency] + + with caplog.at_level(logging.INFO): + cmd.run() + + # The replacement cannot run, and the module it replaced was dropped + # from the run by the replacement, so neither of them produces + # results and the module depending on the replaced one is skipped. + assert RecordingModule.run_order == ["IndependentModule"] + assert ( + "Module ReplacementMissingDependency will be SKIPPED: it depends " + "on module UnavailableDependencyModule, which is not available in " + "this command." in caplog.text + ) + # The skipped dependent is told which module it actually depends on, + # and the module class its author declared. + assert ( + "Module SecondModule will be SKIPPED: it depends on module " + "ReplacementMissingDependency (replacing module FirstModule), " + "itself skipped for depending on unavailable module " + "UnavailableDependencyModule." in caplog.text + ) + + def test_selected_replacement_with_unavailable_dependency_runs_nothing( + self, caplog, tmp_path + ): + cmd = RecordingCommand(module_name="FirstModule", results_path=str(tmp_path)) + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule, IndependentModule] + cmd.custom_modules = [ReplacementMissingDependency] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == [] + assert not hasattr(cmd, "initialized") + assert ( + "Module FirstModule was replaced by module " + "ReplacementMissingDependency, which is run in its place." + in caplog.text + ) + assert "Module ReplacementMissingDependency will be SKIPPED" in caplog.text + assert "No modules will be run" in caplog.text + # Nothing else was selected, so the warnings must not promise that the + # analysis continues right before saying that it does not. + assert "The rest of the analysis will still run" not in caplog.text + # No module ran, so no results were stored next to the command log. + assert [path.name for path in tmp_path.iterdir()] == ["command.log"] + + def test_chained_replacements_are_resolved(self): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [SecondModule, FirstModule] + cmd.custom_modules = [ReplacementModule, ReplacementOfReplacementModule] + + cmd.run() + + assert RecordingModule.run_order == [ + "ReplacementOfReplacementModule", + "SecondModule", + ] + second = next( + module for module in cmd.executed if isinstance(module, SecondModule) + ) + assert second.results == ["replacement of replacement", "second"] + + def test_replacement_which_is_not_a_subclass_warns(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [IndependentModule] + cmd.custom_modules = [UnrelatedReplacementModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == ["UnrelatedReplacementModule"] + assert "is not a subclass of it" in caplog.text + + def test_multiple_modules_replacing_the_same_module_warn(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [ReplacementModule, OtherReplacementModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == [ + "ReplacementModule", + "OtherReplacementModule", + ] + assert cmd.module_replacements == {FirstModule: ReplacementModule} + assert ( + "Modules ReplacementModule and OtherReplacementModule both replace " + "module FirstModule. Both of them will run, FirstModule will not, " + "and modules depending on FirstModule will use the results of " + "ReplacementModule." in caplog.text + ) + assert "overwrite each other's results file" in caplog.text + + def test_module_replacing_its_own_dependency_runs(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [ReplacesOwnDependencyModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == ["ReplacesOwnDependencyModule"] + assert ( + "Module ReplacesOwnDependencyModule depends on module FirstModule, " + "which it also replaces" in caplog.text + ) + + def test_literal_self_dependency_is_still_circular(self, caplog): + class SelfDependentModule(RecordingModule): + pass + + SelfDependentModule.dependencies = (SelfDependentModule,) + + cmd = RecordingCommand() + cmd.modules = [SelfDependentModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == [] + assert not hasattr(cmd, "initialized") + assert "Circular module dependency detected" in caplog.text + + def test_disabled_replacement_keeps_the_replaced_module(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [DisabledReplacementModule] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == ["FirstModule"] + assert cmd.module_replacements == {} + assert logged_substitutions(caplog) == [] + + def test_modules_replacing_each_other_all_run(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.custom_modules = [MutualReplacementOne, MutualReplacementTwo] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == [ + "MutualReplacementOne", + "MutualReplacementTwo", + ] + assert cmd.module_replacements == {} + assert ( + "Modules MutualReplacementOne, MutualReplacementTwo replace each " + "other in a cycle" in caplog.text + ) + assert logged_substitutions(caplog) == [] + + def test_replacement_cycle_of_three_modules_all_run(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.custom_modules = [CycleOneModule, CycleTwoModule, CycleThreeModule] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == [ + "CycleOneModule", + "CycleTwoModule", + "CycleThreeModule", + ] + assert cmd.module_replacements == {} + assert ( + "Modules CycleOneModule, CycleThreeModule, CycleTwoModule replace " + "each other in a cycle" in caplog.text + ) + assert logged_substitutions(caplog) == [] + + def test_selected_replaced_module_name_runs_the_replacement(self, caplog): + cmd = RecordingCommand(module_name="FirstModule") + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [ReplacementModule] + + with caplog.at_level(logging.INFO): + cmd.run() + + assert RecordingModule.run_order == ["ReplacementModule"] + assert ( + "Module FirstModule was replaced by module ReplacementModule" + in caplog.text + ) + + def test_unknown_selected_module_warns_and_stops(self, caplog): + cmd = RecordingCommand(module_name="NoSuchModule") + cmd.name = "check-backup" + cmd.modules = [FirstModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == [] + assert not hasattr(cmd, "initialized") + assert ( + "No module named NoSuchModule is available for the check-backup " + "command" in caplog.text + ) + + def test_selected_module_name_matches_the_replacement(self): + cmd = RecordingCommand(module_name="FirstModule") + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [SameNameReplacementModule] + + cmd.run() + + assert len(cmd.executed) == 1 + assert isinstance(cmd.executed[0], SameNameReplacementModule) + assert cmd.executed[0].results == ["replacement"] + + def test_list_modules_reflects_replacements(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule, IndependentModule] + cmd.custom_modules = [ReplacementModule] + + with caplog.at_level(logging.INFO): + cmd.list_modules() + + listed = [ + record.getMessage() + for record in caplog.records + if "Modules from" in record.getMessage() + ] + assert any("ReplacementModule" in message for message in listed) + assert not any("FirstModule" in message for message in listed) + + def test_modules_sharing_a_slug_are_reported(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.custom_modules = [SharedSlugModule, OtherSharedSlugModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert RecordingModule.run_order == [ + "SharedSlugModule", + "OtherSharedSlugModule", + ] + collisions = [ + record.getMessage() + for record in caplog.records + if "both use the slug" in record.getMessage() + ] + assert len(collisions) == 1 + assert "Modules SharedSlugModule from" in collisions[0] + assert "and OtherSharedSlugModule from" in collisions[0] + assert "both use the slug shared_slug" in collisions[0] + assert "overwrites the results of the other in shared_slug.json" in ( + collisions[0] + ) + + def test_replacement_keeping_the_replaced_slug_is_not_reported(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule] + cmd.custom_modules = [ReplacementKeepingTheSlug] + + with caplog.at_level(logging.WARNING): + cmd.run() + + # The replaced module is no longer part of the run, so taking over its + # slug is what the replacement is for, not a collision. + assert RecordingModule.run_order == ["ReplacementKeepingTheSlug"] + assert ReplacementKeepingTheSlug.get_slug() == FirstModule.get_slug() + assert "both use the slug" not in caplog.text + + def test_modules_with_distinct_slugs_are_not_reported(self, caplog): + cmd = RecordingCommand() + cmd.platform = "ios" + cmd.name = "check-backup" + cmd.modules = [FirstModule, IndependentModule] + cmd.custom_modules = [CustomIOSBackupModule] + + with caplog.at_level(logging.WARNING): + cmd.run() + + assert "both use the slug" not in caplog.text