add tests for the django test suite

scripts/typecheck_django_tests.xsh

@@ -2,10 +2,55 @@ import os
 if not os.path.exists('./django-sources'):
     git clone -b stable/2.1.x https://github.com/django/django.git django-sources
 
-ignored_error_patterns = ["Need type annotation for", "already defined on", "Cannot assign to a"]
-for line in $(mypy --config-file ./scripts/mypy.ini ./django-sources/tests).split('\n'):
-    for pattern in ignored_error_patterns:
-        if pattern in line:
-            break
-    else:
-        print(line)
+IGNORED_ERROR_PATTERNS = [
+    'Need type annotation for',
+    'already defined on',
+    'Cannot assign to a',
+    'cannot perform relative import',
+    'broken_app',
+    'LazySettings',
+    'Cannot infer type of lambda',
+    'Incompatible types in assignment (expression has type "Callable[',
+    '"Callable[[Any], Any]" has no attribute',
+    'Invalid value for a to= parameter'
+]
+TESTS_DIRS = [
+    'absolute_url_overrides',
+    'admin_*',
+    'aggregation*',
+    'annotations'
+]
+
+def check_file_in_the_current_directory(directory, fname):
+    cd @(directory)
+    with ${...}.swap(FNAME=fname):
+        for line in $(mypy --config-file ../../../scripts/mypy.ini $FNAME).split('\n'):
+            for pattern in IGNORED_ERROR_PATTERNS:
+                if pattern in line:
+                    break
+            else:
+                if line:
+                    print(line)
+    cd -
+
+def parse_ls_output_into_fnames(output):
+    fnames = []
+    for line in output.splitlines()[1:]:
+        fnames.append(line.split()[-1])
+    return fnames
+
+all_tests_dirs = []
+for test_dir in TESTS_DIRS:
+    with ${...}.swap(TEST_DIR=test_dir):
+        dirs = g`django-sources/tests/$TEST_DIR`
+        all_tests_dirs.extend(dirs)
+
+for tests_dir in all_tests_dirs:
+    print('Checking ' + tests_dir)
+    abs_dir = os.path.join(os.getcwd(), tests_dir)
+
+    with ${...}.swap(ABS_DIR=abs_dir):
+        ls_output = $(ls $ABS_DIR)
+        for fname in parse_ls_output_into_fnames(ls_output):
+            path_to_check = os.path.join(abs_dir, fname)
+            check_file_in_the_current_directory(abs_dir, fname)