buf: add protobuf linting

Adds protobuf linting hooks using Buf:
	https://docs.buf.build/

Expects buf to be installed locally.

.pre-commit-hooks.yaml

@@ -118,4 +118,22 @@
   files: (?i)\.R$
   pass_filenames: true
   minimum_pre_commit_version: 0.15.0
-  description: 'Run lintr against R code'
+  description: 'Run lintr against R code'
+
+- id: buf-lint
+  name: 'Lint protobuf files'
+  entry: buf-lint.sh
+  types: [proto]
+  language: 'script'
+  pass_filenames: false
+  minimum_pre_commit_version: 0.15.0
+  description: "Runs buf lint at the repo root"
+
+- id: buf-breaking
+  name: 'Check protobuf for breaking changes'
+  entry: buf-breaking.sh
+  types: [proto]
+  language: 'script'
+  pass_filenames: false
+  minimum_pre_commit_version: 0.15.0
+  description: "Runs buf breaking at the repo root"

README.md

@@ -18,6 +18,8 @@ Hooks:
 * `rust-fmt`: runs `cargo fmt --all`
 * `r-stylr`: runs [`stylr`] to format R code
 * `r-lintr`: static analysis of R code with [`lintr`]
+* `buf-lint`: runs [`buf`] lints against protobuf files
+* `buf-breaking`: protobuf breaking change detection using [`buf`]
 
 ## Example config
 
@@ -64,7 +66,7 @@ repos:
         stages: [commit, push]
 
       - id: rust-clippy
-        #args: [                           # Optionally override default configured lints
+        # args: [                          # Optionally override default configured lints
         #  "-D rust_2018_idioms",
         #  "-D missing_docs",
         #]
@@ -81,6 +83,15 @@ repos:
 
       - id: r-lintr
         stages: [commit, push]
+        stages: [commit, push]
+
+      - id: buf-lint
+        stages: [commit, push]
+
+      - id: buf-breaking
+        # Checks against 'master' branch by defaut, change with:
+        # args: [".git#tag=v1.0.0"]
+        stages: [commit, push]
 ```
 
 ## Tagged TODOs
@@ -129,4 +140,5 @@ When adding new hooks you can run `pre-commit try-repo .` for a quick syntax che
 [dep]: https://github.com/golang/dep
 [`post-checkout`]: https://git-scm.com/docs/githooks#_post_checkout
 [`stylr`]: https://styler.r-lib.org/
-[`lintr`]: https://github.com/jimhester/lintr
+[`lintr`]: https://github.com/jimhester/lintr
+[`buf`]: https://buf.build/

buf-breaking.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+# Protobuf breaking change detection with Buf: https://docs.buf.build/
+#
+# To run the checks locally:
+#   buf breaking
+#
+# To view the breaking change lints:
+#   buf config ls-breaking-rules
+
+set -euo pipefail
+
+# Default to checking against the local master Git branch
+against=${1-'.git#branch=master'};
+
+buf breaking "${against}"

buf-lint.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env bash
+
+# Protobuf linting with Buf: https://docs.buf.build/
+#
+# To run the lints locally:
+#   buf lint
+#
+# To view the available lints and their descriptions:
+#   buf config ls-lint-rules
+
+set -euo pipefail
+
+buf lint "$@"