lint: resolve existing mypy type errors

Adds annotations and re-workes dataflow to satisfy existing mypy issues,
without adding any additional type annotations to, eg, function
signatures.

There will probably be many more type errors when annotations are all
added.

3 files changed, 27 insertions, 22 deletions

diff --git a/python/fatcat_tools/importers/crossref.py b/python/fatcat_tools/importers/crossref.py
index 606d4bb1..d0017002 100644
--- a/python/fatcat_tools/importers/crossref.py
+++ b/python/fatcat_tools/importers/crossref.py
@@ -393,8 +393,6 @@ class CrossrefImporter(EntityImporter):
             ):
                 if clean(rm.get(k)):
                     ref_extra[k] = clean(rm[k])
-            if not ref_extra:
-                ref_extra = None
             refs.append(
                 fatcat_openapi_client.ReleaseRef(
                     index=i,
@@ -406,7 +404,7 @@ class CrossrefImporter(EntityImporter):
                     title=clean(rm.get("article-title")),
                     locator=clean(rm.get("first-page")),
                     # TODO: just dump JSON somewhere here?
-                    extra=ref_extra,
+                    extra=ref_extra or None,
                 )
             )
 
@@ -421,8 +419,8 @@ class CrossrefImporter(EntityImporter):
             )
 
         # extra fields
-        extra = dict()
-        extra_crossref = dict()
+        extra: Dict[str, Any] = dict()
+        extra_crossref: Dict[str, Any] = dict()
         # top-level extra keys
         if not container_id:
             if obj.get("container-title"):
@@ -471,13 +469,13 @@ class CrossrefImporter(EntityImporter):
             "dissertation",
             "book-chapter",
         ):
-            release_stage = "published"
+            release_stage: Optional[str] = "published"
         else:
             # unknown
             release_stage = None
 
         # external identifiers
-        extids: Dict[str, Any] = self.lookup_ext_ids(doi=obj["DOI"].lower())
+        extids: Dict[str, Any] = self.lookup_ext_ids(doi=obj["DOI"].lower()) or {}
 
         # filter out unreasonably huge releases
         if len(abstracts) > 100:
@@ -512,7 +510,7 @@ class CrossrefImporter(EntityImporter):
 
         title: Optional[str] = None
         if obj.get("title"):
-            title = clean(obj.get("title")[0], force_xml=True)
+            title = clean(obj["title"][0], force_xml=True)
             if not title or len(title) <= 1:
                 # title can't be just a single character
                 self.counts["skip-blank-title"] += 1
@@ -520,15 +518,13 @@ class CrossrefImporter(EntityImporter):
 
         subtitle = None
         if obj.get("subtitle"):
-            subtitle = clean(obj.get("subtitle")[0], force_xml=True)
+            subtitle = clean(obj["subtitle"][0], force_xml=True)
             if not subtitle or len(subtitle) <= 1:
                 # subtitle can't be just a single character
                 subtitle = None
 
         if extra_crossref:
             extra["crossref"] = extra_crossref
-        if not extra:
-            extra = None
 
         re = ReleaseEntity(
             work_id=None,
@@ -556,10 +552,10 @@ class CrossrefImporter(EntityImporter):
             pages=clean(obj.get("page")),
             language=clean(obj.get("language")),
             license_slug=license_slug,
-            extra=extra,
-            abstracts=abstracts,
-            contribs=contribs,
-            refs=refs,
+            extra=extra or None,
+            abstracts=abstracts or None,
+            contribs=contribs or None,
+            refs=refs or None,
         )
         return re
 
diff --git a/python/fatcat_tools/importers/dblp_release.py b/python/fatcat_tools/importers/dblp_release.py
index 5baa6cd6..e73e5f33 100644
--- a/python/fatcat_tools/importers/dblp_release.py
+++ b/python/fatcat_tools/importers/dblp_release.py
@@ -26,6 +26,7 @@ import sys  # noqa: F401
 import warnings
 from typing import Any, List, Optional
 
+import bs4
 import fatcat_openapi_client
 
 from fatcat_tools.importers.common import EntityImporter
@@ -420,7 +421,9 @@ class DblpReleaseImporter(EntityImporter):
             )
         )
 
-    def dblp_contribs(self, authors: List[dict]) -> List[fatcat_openapi_client.ReleaseContrib]:
+    def dblp_contribs(
+        self, elem: bs4.element.Tag
+    ) -> List[fatcat_openapi_client.ReleaseContrib]:
         """
         - author (multiple; each a single string)
             => may have HTML entities
@@ -431,21 +434,23 @@ class DblpReleaseImporter(EntityImporter):
         """
         contribs = []
         index = 0
-        for elem in authors.find_all("author"):
+        for elem in elem.find_all("author"):
             contrib = self.dblp_contrib_single(elem)
             contrib.role = "author"
             contrib.index = index
             contribs.append(contrib)
             index += 1
 
-        for elem in authors.find_all("editor"):
+        for elem in elem.find_all("editor"):
             contrib = self.dblp_contrib_single(elem)
             contrib.role = "editor"
             contribs.append(contrib)
 
         return contribs
 
-    def dblp_contrib_single(self, elem: Any) -> fatcat_openapi_client.ReleaseContrib:
+    def dblp_contrib_single(
+        self, elem: bs4.element.Tag
+    ) -> fatcat_openapi_client.ReleaseContrib:
         """
         In the future, might try to implement creator key-ificiation and lookup here.
 
@@ -461,11 +466,15 @@ class DblpReleaseImporter(EntityImporter):
         raw_name = clean_str(elem.text)
 
         # remove number in author name, if present
-        if raw_name.split()[-1].isdigit():
+        if raw_name and raw_name.split()[-1].isdigit():
             raw_name = " ".join(raw_name.split()[:-1])
 
         if elem.get("orcid"):
-            orcid = clean_orcid(elem["orcid"])
+            orcid_val = elem["orcid"]
+            if isinstance(orcid_val, list):
+                orcid = clean_orcid(orcid_val[0])
+            else:
+                orcid = clean_orcid(orcid_val)
             if orcid:
                 creator_id = self.lookup_orcid(orcid)
                 if not creator_id:
diff --git a/python/fatcat_tools/importers/doaj_article.py b/python/fatcat_tools/importers/doaj_article.py
index cd063337..56045ea7 100644
--- a/python/fatcat_tools/importers/doaj_article.py
+++ b/python/fatcat_tools/importers/doaj_article.py
@@ -382,7 +382,7 @@ class DoajArticleImporter(EntityImporter):
             if not license.get("open_access"):
                 continue
             slug = license.get("type")
-            if slug.startswith("CC "):
+            if slug and slug.startswith("CC "):
                 slug = slug.replace("CC ", "cc-").lower()
                 return slug
         return None