Automatic PR labeler (#6912)

* label all new prs with needs-triage

* label new prs according to files they touch

* newlines at end of files

Author: TomNicholas

.github/labeler.yml

@@ -0,0 +1,82 @@
+Automation:
+  - .github/*
+  - .github/**/*
+
+CI:
+  - ci/*
+  - ci/**/*
+
+dependencies:
+  - requirements.txt
+  - ci/requirements/*
+
+documentation:
+  - doc/*
+  - doc/**/*
+
+topic-arrays:
+  - xarray/core/duck_array_ops.py
+
+topic-backends:
+  - xarray/backends/*
+  - xarray/backends/**/*
+
+topic-cftime:
+  - xarray/coding/*time*
+
+topic-CF conventions:
+  - xarray/conventions.py
+
+topic-combine:
+  - xarray/core/combine.py
+
+topic-dask:
+  - xarray/core/dask*
+  - xarray/core/parallel.py
+
+topic-DataTree:
+  - xarray/core/datatree*
+
+topic-faq:
+  - doc/howdoi.rst
+
+topic-groupby:
+  - xarray/core/groupby.py
+
+topic-html-repr:
+  - xarray/core/formatting_html.py
+
+topic-hypothesis:
+  - xarray/properties/*
+  - xarray/testing/strategies/*
+
+topic-indexing:
+  - xarray/core/indexes.py
+  - xarray/core/indexing.py
+
+topic-performance:
+  - asv_bench/benchmarks/*
+  - asv_bench/benchmarks/**/*
+
+topic-plotting:
+  - xarray/plot/*
+  - xarray/plot/**/*
+
+topic-rolling:
+  - xarray/core/rolling.py
+  - xarray/core/rolling_exp.py
+
+topic-testing:
+  - conftest.py
+  - xarray/testing.py
+  - xarray/testing/*
+
+topic-typing:
+  - xarray/core/types.py
+
+topic-zarr:
+  - xarray/backends/zarr.py
+
+io:
+  - xarray/backends/*
+  - xarray/backends/**/*

.github/workflows/label-all.yml

@@ -0,0 +1,14 @@
+name: "Issue and PR Labeler"
+on:
+  pull_request:
+    types: [opened]
+  issues:
+    types: [opened, reopened]
+jobs:
+  label-all-on-open:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: andymckay/[email protected]
+        with:
+          add-labels: "needs triage"
+          ignore-if-labeled: false

.github/workflows/label-prs.yml

@@ -0,0 +1,12 @@
+name: "PR Labeler"
+on:
+- pull_request_target
+
+jobs:
+  label:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/labeler@main
+      with:
+        repo-token: "${{ secrets.GITHUB_TOKEN }}"
+        sync-labels: false