Add coverage reporting and expand ERCOT tests

.github/workflows/ci.yml

@@ -47,3 +47,10 @@ jobs:
 
       - name: Run tests with coverage
         run: just test-coverage
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v5
+        with:
+          file: ./coverage.xml
+          fail_ci_if_error: true
+          token: ${{ secrets.CODECOV_TOKEN }}

.pre-commit-config.yaml

@@ -0,0 +1,26 @@
+# Pre-commit hooks for tinygrid
+# Install: uv run pre-commit install
+# Run manually: uv run pre-commit run --all-files
+
+repos:
+  # Use local hooks to respect project configs (ruff.toml, pyrightconfig.json)
+  - repo: local
+    hooks:
+      - id: ruff
+        name: ruff
+        entry: uv run ruff check --fix --unsafe-fixes
+        language: system
+        types: [python]
+
+      - id: ruff-format
+        name: ruff-format
+        entry: uv run ruff format
+        language: system
+        types: [python]
+
+      - id: pyright
+        name: pyright
+        entry: uv run pyright
+        language: system
+        types: [python]
+        pass_filenames: false

README.md

@@ -1,6 +1,7 @@
 # Tiny Grid
 
 [![CI](https://github.com/kvkenyon/tinygrid/actions/workflows/ci.yml/badge.svg)](https://github.com/kvkenyon/tinygrid/actions)
+[![codecov](https://codecov.io/gh/kvkenyon/tinygrid/branch/main/graph/badge.svg)](https://codecov.io/gh/kvkenyon/tinygrid)
 
 A Python SDK for accessing electricity grid data from US Independent System Operators (ISOs).
 
@@ -195,19 +196,37 @@ just test
 # Run tests with coverage
 just test-coverage
 
-# Lint
+# Lint and format
 just lint
-
-# Format
 just format
+just lint-fix  # Auto-fix lint issues
 
 # Type check
 just type-check
 
-# Run all checks
+# Run all checks (lint, format, type-check, test)
 just check
 ```
 
+### Pre-commit Hooks
+
+Pre-commit hooks automatically run linting and formatting before each commit to catch issues early.
+
+```bash
+# Install hooks (one-time setup after cloning)
+just hooks-install
+
+# Run hooks manually on all files
+just hooks-run
+```
+
+The hooks run:
+- **ruff** - Linting with auto-fix
+- **ruff-format** - Code formatting
+- **pyright** - Type checking
+
+If a hook fails, fix the issues and re-commit. Ruff auto-fixes will be staged automatically.
+
 ## License
 
 MIT