Update linting config

Author: charlieegan3

.github/workflows/ci.yaml

@@ -20,3 +20,12 @@ jobs:
           echo "Please update the table of contents with make toc"
           exit 1
         fi
+    - run: make markdownlint
+    - run: git diff
+    - run: |
+        if [ -z "$(git status --porcelain)" ]; then
+          echo "No changes"
+        else
+          echo "Please fix the markdownlint errors"
+          exit 1
+        fi

.markdownlint.yaml

@@ -0,0 +1,44 @@
+default: true
+
+# MD013/line-length
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md013.md
+MD013:
+  line_length: 120
+  heading_line_length: 80
+  code_blocks: false
+  tables: false
+  headings: true
+
+# MD024/no-duplicate-heading
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md024.md
+MD024:
+  siblings_only: true
+
+# MD026/no-trailing-punctuation
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md026.md
+MD026:
+  # Punctuation characters
+  punctuation: ".,;:，；：！"
+
+# MD031/blanks-around-fences
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md031.md
+MD031: false
+
+# MD033/no-inline-html
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md033.md
+MD033:
+  allowed_elements:
+  - br
+  - details
+  - img
+  - strong
+  - summary
+
+# MD036/no-emphasis-as-heading
+# https://github.com/DavidAnson/markdownlint/blob/v0.32.1/doc/md036.md
+MD036: false
+
+MD004:
+  style: dash
+
+MD010: false

Makefile

@@ -1,4 +1,10 @@
+PHONY: deps
+deps:
+	npm install
+
 PHONY: toc
-toc:
-	npm install # installs the markdown-toc at the expected version from package.json
+toc: deps
 	npx markdown-toc -i style-guide.md --bullets="*" --maxdepth=3
+
+markdownlint: deps
+	npx markdownlint-cli2 style-guide.md --config=.markdownlint.yaml