maintain: modernize and check types

.pre-commit-config.yaml

@@ -1,29 +1,37 @@
 repos:
 - repo: https://github.com/pre-commit/pre-commit-hooks
-  rev: v4.5.0
+  rev: cef0300fd0fc4d2a87a85fa2093c6b283ea36f4b  # frozen: v5.0.0
   hooks:
   - id: end-of-file-fixer
   - id: mixed-line-ending
   - id: trailing-whitespace
   - id: check-yaml
   - id: check-toml
 - repo: https://github.com/pre-commit/pygrep-hooks
-  rev: v1.10.0
+  rev: 3a6eb0fadf60b3cccfd80bad9dbb6fae7e47b316  # frozen: v1.10.0
   hooks:
   - id: python-check-blanket-noqa
-- repo: https://github.com/timothycrosley/isort
-  rev: 5.13.2
+- repo: https://github.com/PyCQA/isort
+  rev: c235f5e450b4b84e58d114ed4c589cbf454175a3  # frozen: 5.13.2
   hooks:
   - id: isort
 - repo: https://github.com/psf/black
-  rev: 24.2.0
+  rev: 1b2427a2b785cc4aac97c19bb4b9a0de063f9547  # frozen: 24.10.0
   hooks:
   - id: black
 - repo: https://github.com/PyCQA/flake8
-  rev: 7.0.0
+  rev: e43806be3607110919eff72939fda031776e885a  # frozen: 7.1.1
   hooks:
   - id: flake8
     additional_dependencies:
     - flake8-bugbear>=20.11.1
     - flake8-builtins>=1.5.3
     - flake8-comprehensions>=3.3.1
+- repo: https://github.com/pre-commit/mirrors-mypy
+  rev: f56614daa94d5cd733d3b7004c5df9caad267b4a  # frozen: v1.13.0
+  hooks:
+  - id: mypy
+    args: ["--scripts-are-modules"]
+    additional_dependencies:
+    - mdformat
+    files: ^src/mdformat_tables/.+\.py$

pyproject.toml

@@ -80,3 +80,22 @@ deps = ["pre-commit"]
 commands = [
     ["pre-commit", "run", "--config", ".pre-commit-test.yaml", { replace = "posargs", default = ["--all-files", "--verbose", "--show-diff-on-failure"], extend = true }],
 ]
+
+
+[tool.mypy]
+show_error_codes = true
+warn_unreachable = true
+warn_unused_ignores = true
+warn_redundant_casts = true
+warn_unused_configs = true
+# Disabling incremental mode is required for `warn_unused_configs = true` to work
+incremental = false
+disallow_untyped_defs = true
+check_untyped_defs = true
+strict_equality = true
+implicit_reexport = false
+no_implicit_optional = true
+
+[[tool.mypy.overrides]]
+module = "wcwidth.*"
+ignore_missing_imports = true

src/mdformat_tables/plugin.py

@@ -1,5 +1,5 @@
 import argparse
-from typing import Iterable, List, Mapping, Sequence, Union
+from collections.abc import Iterable, Mapping, Sequence
 
 from markdown_it import MarkdownIt
 from mdformat.renderer import RenderContext, RenderTreeNode
@@ -40,8 +40,8 @@ def _center(text: str, width: int) -> str:
 
 def _to_string(
     rows: Sequence[Sequence[str]], align: Sequence[Sequence[str]], widths: Sequence[int]
-) -> List[str]:
-    def join_row(items: Union[Iterable[str], Sequence[str]]) -> str:
+) -> list[str]:
+    def join_row(items: Iterable[str]) -> str:
         return "| " + " | ".join(items) + " |"
 
     def format_delimiter_cell(index: int, align: str) -> str:
@@ -60,13 +60,13 @@ def format_delimiter_cell(index: int, align: str) -> str:
     delimiter = join_row(
         (format_delimiter_cell(i, al) for i, al in enumerate(align[0]))
     )
-    rows = [
+    joined_rows = (
         join_row(
             pad[_al](text, widths[i]) for i, (text, _al) in enumerate(zip(row, aligns))
         )
         for row, aligns in zip(rows[1:], align[1:])
-    ]
-    return [header, delimiter, *rows]
+    )
+    return [header, delimiter, *joined_rows]
 
 
 def _render_table(node: RenderTreeNode, context: RenderContext) -> str:
@@ -80,8 +80,8 @@ def _render_table(node: RenderTreeNode, context: RenderContext) -> str:
     compact_tables_from_api = context.options["mdformat"].get("compact_tables")
     compact_tables = compact_tables_from_cli_or_toml or compact_tables_from_api
     # gather rendered cell content into row * column array
-    rows: List[List[str]] = []
-    align: List[List[str]] = []
+    rows: list[list[str]] = []
+    align: list[list[str]] = []
     for descendant in node.walk(include_self=False):
         if descendant.type == "tr":
             rows.append([])