check heading increase (#3159)

seahub/api2/endpoints/markdown_lint.py

@@ -12,7 +12,7 @@ from rest_framework import status
 from seahub.api2.authentication import TokenAuthentication
 from seahub.api2.throttling import UserRateThrottle
 from seahub.api2.utils import api_error
-from seahub.utils.markdown_lint import check_header_one, check_heading_end_with
+from seahub.utils.markdown_lint import check_heading_one, check_heading_end_with, check_heading_increase
 
 
 logger = logging.getLogger(__name__)
@@ -42,13 +42,18 @@ class MarkdownLintView(APIView):
         document_nodes = slate["document"]["nodes"]
 
         # check h1
-        header_one_issue_list = check_header_one(document_nodes)
-        if len(header_one_issue_list) > 0:
-            issue_list.extend(header_one_issue_list)
+        heading_one_issue_list = check_heading_one(document_nodes)
+        if len(heading_one_issue_list) > 0:
+            issue_list.extend(heading_one_issue_list)
 
         # check heading_end_with
         heading_end_issue_list = check_heading_end_with(document_nodes)
         if len(heading_end_issue_list) > 0:
             issue_list.extend(heading_end_issue_list)
 
+        # check heading_increase
+        heading_increase_issue_list = check_heading_increase(document_nodes)
+        if len(heading_increase_issue_list) > 0:
+            issue_list.extend(heading_increase_issue_list)
+
         return Response({"issue_list": issue_list}, status=status.HTTP_200_OK)

seahub/utils/markdown_lint.py

@@ -2,18 +2,18 @@
 # -*- coding: utf-8 -*-
 
 
-def check_header_one(document_nodes):
+def check_heading_one(document_nodes):
 
     issue_list = []
-    issue_count = 0
-    position = []
+    h1_count = 0
+    position_list = []
 
-    for index, node in enumerate(document_nodes):
+    for position, node in enumerate(document_nodes):
         if node["type"] == "header_one":
-            issue_count += 1  # issue < 1: missing h1; issue > 1: multiple h1.
-            position.append(index)
+            h1_count += 1
+            position_list.append(position)
 
-    if issue_count < 1:
+    if h1_count < 1:
         issue = dict()
         issue["issue"] = "Missing h1."
         issue["issue_code"] = "missing_h1"
@@ -26,25 +26,75 @@ def check_heading_end_with(document_nodes):
 
     issue_list = []
     issue_count = 0
-    position = []
+    position_list = []
 
-    for index, node in enumerate(document_nodes):
+    for position, node in enumerate(document_nodes):
         if node["type"].startswith("header_") and (
                 node["nodes"][0]["leaves"][0]["text"].endswith(":") or
                 node["nodes"][0]["leaves"][0]["text"].endswith("：")):
             issue_count += 1
-            position.append(index)
+            position_list.append(position)
 
     if issue_count > 0:
         issue = dict()
         issue["issue"] = "Heading end with colon."
         issue["issue_code"] = "heading_end_with_colon"
         issue["detail"] = []
-        for index in position:
+        for position in position_list:
             detail = dict()
-            detail["position"] = index
+            detail["position"] = position
             detail["description"] = "Trailing punctuation in heading should not be a colon."
             issue["detail"].append(detail)
         issue_list.append(issue)
 
     return issue_list
+
+
+def check_heading_increase(document_nodes):
+    """ Only check h1, h2, h3, h4. Don't check h5, h6.
+    """
+
+    issue_list = []
+    issue_count = 0
+    heading_list = []
+    position_list = []
+
+    for position, node in enumerate(document_nodes):
+        # init heading data, e.g. {"heading_level": 2, "position": 1}
+        heading_dict = dict()
+        if node["type"].startswith("header_one"):
+            heading_dict["heading_level"] = 1
+            heading_dict["position"] = position
+            heading_list.append(heading_dict)
+        elif node["type"].startswith("header_two"):
+            heading_dict["heading_level"] = 2
+            heading_dict["position"] = position
+            heading_list.append(heading_dict)
+        elif node["type"].startswith("header_three"):
+            heading_dict["heading_level"] = 3
+            heading_dict["position"] = position
+            heading_list.append(heading_dict)
+        elif node["type"].startswith("header_four"):
+            heading_dict["heading_level"] = 4
+            heading_dict["position"] = position
+            heading_list.append(heading_dict)
+
+    for index, heading in enumerate(heading_list[1:]):
+        # The level of the current heading minus the level of the previous heading
+        if heading["heading_level"] - heading_list[index]["heading_level"] > 1:
+            issue_count += 1
+            position_list.append(heading["position"])
+
+    if issue_count > 0:
+        issue = dict()
+        issue["issue"] = "Heading increase irregular."
+        issue["issue_code"] = "heading_increase_irregular"
+        issue["detail"] = []
+        for position in position_list:
+            detail = dict()
+            detail["position"] = position
+            detail["description"] = "Heading levels should only increment by one level at a time."
+            issue["detail"].append(detail)
+        issue_list.append(issue)
+
+    return issue_list