Fix some fine-grained module error message bugs

Author: msullivan

mypy/build.py

@@ -1909,6 +1909,34 @@ def write_cache(self) -> None:
             self.mark_interface_stale()
             self.interface_hash = new_interface_hash
 
+    def verify_dependencies(self) -> None:
+        """Report errors for import targets in module that don't exist."""
+        # Strip out indirect dependencies. See comment in build.load_graph().
+        manager = self.manager
+        dependencies = [dep for dep in self.dependencies
+                        if self.priorities.get(dep) != PRI_INDIRECT]
+        assert self.ancestors is not None
+        for dep in dependencies + self.suppressed + self.ancestors:
+            if dep not in manager.modules and not manager.options.ignore_missing_imports:
+                line = self.dep_line_map.get(dep, 1)
+                try:
+                    if dep in self.ancestors:
+                        state, ancestor = None, self  # type: (Optional[State], Optional[State])
+                    else:
+                        state, ancestor = self, None
+                    # Called just for its side effects of producing diagnostics.
+                    find_module_and_diagnose(
+                        manager, self.options, dep,
+                        caller_state=state, caller_line=line,
+                        ancestor_for=ancestor)
+                except Exception:
+                    # Swallow up any exception while generating a diagnostic.
+                    # This can actually include CompileErrors that get generated in
+                    # fine-grained mode when an __init__.py is deleted, if a module
+                    # that was in that package has targets reprocessed before
+                    # it is renamed.
+                    pass
+
     def dependency_priorities(self) -> List[int]:
         return [self.priorities.get(dep, PRI_HIGH) for dep in self.dependencies]
 

mypy/server/update.py

@@ -594,18 +594,6 @@ def get_all_changed_modules(root_module: str,
     return changed_modules
 
 
-def verify_dependencies(state: State, manager: BuildManager) -> None:
-    """Report errors for import targets in module that don't exist."""
-    # Strip out indirect dependencies. See comment in build.load_graph().
-    dependencies = [dep for dep in state.dependencies if state.priorities.get(dep) != PRI_INDIRECT]
-    for dep in dependencies + state.suppressed:  # TODO: ancestors?
-        if dep not in manager.modules and not state.options.ignore_missing_imports:
-            assert state.tree
-            line = state.dep_line_map.get(dep, 1)
-            assert state.path
-            module_not_found(manager, line, state, dep)
-
-
 def collect_dependencies(new_modules: Mapping[str, Optional[MypyFile]],
                          deps: Dict[str, Set[str]],
                          graph: Dict[str, State]) -> None:
@@ -879,7 +867,7 @@ def key(node: DeferredNode) -> int:
     update_deps(module_id, nodes, graph, deps, options)
 
     # Report missing imports.
-    verify_dependencies(graph[module_id], manager)
+    graph[module_id].verify_dependencies()
 
     return new_triggered
 

mypy/test/testfinegrained.py

@@ -222,7 +222,7 @@ def parse_sources(self, program_text: str,
         m = re.search('# cmd: mypy ([a-zA-Z0-9_./ ]+)$', program_text, flags=re.MULTILINE)
         regex = '# cmd{}: mypy ([a-zA-Z0-9_./ ]+)$'.format(incremental_step)
         alt_m = re.search(regex, program_text, flags=re.MULTILINE)
-        if alt_m is not None and incremental_step > 1:
+        if alt_m is not None:
             # Optionally return a different command if in a later step
             # of incremental mode, otherwise default to reusing the
             # original cmd.

test-data/unit/fine-grained-modules.test

@@ -1632,3 +1632,112 @@ class Foo:
 [out]
 ==
 a.py:3: error: Argument 1 to "foo" of "Foo" has incompatible type "int"; expected "str"
+
+[case testSkipButDontIgnore1]
+# cmd: mypy a.py c.py
+# flags: --follow-imports=skip
+[file a.py]
+import b
+from c import x
+[file b.py]
+[file c.py]
+x = 1
+[file c.py.2]
+x = '2'
+[out]
+==
+
+[case testSkipButDontIgnore2]
+# cmd: mypy a.py c.py
+# flags: --follow-imports=skip
+[file a.py]
+from c import x
+import b
+[file b.py]
+[file c.py]
+x = 1
+[file c.py.2]
+x = '2'
+[file c.py.3]
+x = 2
+[delete b.py.3]
+[out]
+==
+==
+a.py:2: error: Cannot find module named 'b'
+a.py:2: note: (Perhaps setting MYPYPATH or using the "--ignore-missing-imports" flag would help)
+
+[case testErrorButDontIgnore1]
+# cmd: mypy a.py c.py
+# flags: --follow-imports=error
+[file a.py]
+from c import x
+import b
+[file b.py]
+[file c.py]
+x = 1
+[file c.py.2]
+x = '2'
+[out]
+a.py:2: note: Import of 'b' ignored
+a.py:2: note: (Using --follow-imports=error, module not passed on command line)
+==
+a.py:2: note: Import of 'b' ignored
+a.py:2: note: (Using --follow-imports=error, module not passed on command line)
+
+[case testErrorButDontIgnore2]
+# cmd1: mypy a.py c.py b.py
+# cmd2: mypy a.py c.py
+# flags: --follow-imports=error
+[file a.py]
+from c import x
+import b
+[file b.py]
+[file c.py]
+x = 1
+[file c.py.2]
+x = '2'
+[out]
+==
+a.py:2: note: Import of 'b' ignored
+a.py:2: note: (Using --follow-imports=error, module not passed on command line)
+
+-- This test fails because p.b doesn't seem to trigger p properly...
+[case testErrorButDontIgnore3-skip]
+# cmd1: mypy a.py c.py p/b.py p/__init__.py
+# cmd2: mypy a.py c.py p/b.py
+# flags: --follow-imports=error --verbose
+[file a.py]
+from c import x
+from p.b import y
+[file p/b.py]
+y = 12
+[file p/__init__.py]
+[file c.py]
+x = 1
+[file c.py.2]
+x = '2'
+[out]
+==
+p/b.py: note: Ancestor package 'p' ignored
+p/b.py: note: (Using --follow-imports=error, submodule passed on command line)
+
+[case testErrorButDontIgnore4]
+# cmd: mypy a.py z.py p/b.py p/__init__.py
+# cmd2: mypy a.py p/b.py
+# flags: --follow-imports=error
+[file a.py]
+from p.b import y
+[file p/b.py]
+from z import x
+y = 12
+[file p/__init__.py]
+[file z.py]
+x = 1
+[delete z.py.2]
+[out]
+==
+p/b.py: note: Ancestor package 'p' ignored
+p/b.py: note: (Using --follow-imports=error, submodule passed on command line)
+p/b.py:1: error: Cannot find module named 'z'
+p/b.py:1: note: (Perhaps setting MYPYPATH or using the "--ignore-missing-imports" flag would help)