Initial commit

Author: alexeagle

.bazelrc

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+# Bazel settings that apply to this repository.
+# Take care to document any settings that you expect users to apply.
+# Settings that apply only to CI are in .github/workflows/ci.bazelrc
+
+
+# Load any settings specific to the current user.
+# .bazelrc.user should appear in .gitignore so that settings are not shared with team members
+# This needs to be last statement in this
+# config, as the user configuration should be able to overwrite flags from this file.
+# See https://docs.bazel.build/versions/master/best-practices.html#bazelrc
+# (Note that we use .bazelrc.user so the file appears next to .bazelrc in directory listing,
+# rather than user.bazelrc as suggested in the Bazel docs)
+try-import %workspace%/.bazelrc.user

.bazelversion

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+5.0.0
+# The first line of this file is used by Bazelisk and Bazel to be sure
+# the right version of Bazel is used to build and test this repo.
+# This also defines which version is used on CI.
+#
+# Note that you should also run integration_tests against other Bazel
+# versions you support.

.github/workflows/ci.bazelrc

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+# This file contains Bazel settings to apply on CI only.
+# It is referenced with a --bazelrc option in the call to bazel in ci.yaml
+
+# Debug where options came from
+build --announce_rc
+# This directory is configured in GitHub actions to be persisted between runs.
+build --disk_cache=~/.cache/bazel
+build --repository_cache=~/.cache/bazel-repo
+# Don't rely on test logs being easily accessible from the test runner,
+# though it makes the log noisier.
+test --test_output=errors
+# Allows tests to run bazelisk-in-bazel, since this is the cache folder used
+test --test_env=XDG_CACHE_HOME

.github/workflows/ci.yaml

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+name: CI
+
+# Controls when the action will run.
+on:
+  # Triggers the workflow on push or pull request events but only for the main branch
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  test:
+    # The type of runner that the job will run on
+    runs-on: ubuntu-latest
+
+    # Steps represent a sequence of tasks that will be executed as part of the job
+    steps:
+      # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+      - uses: actions/checkout@v2
+      # Cache build and external artifacts so that the next ci build is incremental.
+      # Because github action caches cannot be updated after a build, we need to
+      # store the contents of each build in a unique cache key, then fall back to loading
+      # it on the next ci run. We use hashFiles(...) in the key and restore-keys- with
+      # the prefix to load the most recent cache for the branch on a cache miss. You
+      # should customize the contents of hashFiles to capture any bazel input sources,
+      # although this doesn't need to be perfect. If none of the input sources change
+      # then a cache hit will load an existing cache and bazel won't have to do any work.
+      # In the case of a cache miss, you want the fallback cache to contain most of the
+      # previously built artifacts to minimize build time. The more precise you are with
+      # hashFiles sources the less work bazel will have to do.
+      - name: Mount bazel caches
+        uses: actions/cache@v2
+        with:
+          path: |
+            "~/.cache/bazel"
+            "~/.cache/bazel-repo"
+          key: bazel-cache-${{ hashFiles('**/BUILD.bazel', '**/*.bzl', 'WORKSPACE') }}
+          restore-keys: bazel-cache-
+      - name: bazel test //...
+        env:
+          # Bazelisk will download bazel to here, ensure it is cached between runs.
+          XDG_CACHE_HOME: ~/.cache/bazel-repo
+        run: bazel --bazelrc=.github/workflows/ci.bazelrc --bazelrc=.bazelrc test //...

.github/workflows/release.yml

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+# Cut a release whenever a new tag is pushed to the repo.
+# You should use an annotated tag, like `git tag -a v1.2.3`
+# and put the release notes into the commit message for the tag.
+name: Release
+
+on:
+  push:
+    tags:
+      - "v*.*.*"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Mount bazel caches
+        uses: actions/cache@v2
+        with:
+          path: |
+            "~/.cache/bazel"
+            "~/.cache/bazel-repo"
+          key: bazel-cache-${{ hashFiles('**/BUILD.bazel', '**/*.bzl', 'WORKSPACE') }}
+          restore-keys: bazel-cache-
+      - name: bazel test //...
+        env:
+          # Bazelisk will download bazel to here
+          XDG_CACHE_HOME: ~/.cache/bazel-repo
+        run: bazel --bazelrc=.github/workflows/ci.bazelrc --bazelrc=.bazelrc test //...
+      - name: Prepare workspace snippet
+        run: .github/workflows/workspace_snippet.sh ${{ env.GITHUB_REF_NAME }} > release_notes.txt
+      - name: Release
+        uses: softprops/action-gh-release@v1
+        with:
+          prerelease: true
+          # Use GH feature to populate the changelog automatically
+          generate_release_notes: true
+          body_path: release_notes.txt

.github/workflows/workspace_snippet.sh

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+#!/usr/bin/env bash
+
+set -o errexit -o nounset -o pipefail
+
+# Set by GH actions, see
+# https://docs.github.com/en/actions/learn-github-actions/environment-variables#default-environment-variables
+TAG=${GITHUB_REF_NAME}
+PREFIX="rules_mylang-${TAG:1}"
+SHA=$(git archive --format=tar --prefix=${PREFIX}/ ${TAG} | gzip | shasum -a 256 | awk '{print $1}')
+
+cat << EOF
+WORKSPACE snippet:
+\`\`\`starlark
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+http_archive(
+    name = "com_myorg_rules_mylang",
+    sha256 = "${SHA}",
+    strip_prefix = "${PREFIX}",
+    url = "https://github.com/myorg/rules_mylang/archive/refs/tags/${TAG}.tar.gz",
+)
+
+# Fetches the rules_mylang dependencies.
+# If you want to have a different version of some dependency,
+# you should fetch it *before* calling this.
+# Alternatively, you can skip calling this function, so long as you've
+# already fetched all the dependencies.
+load("@com_myorg_rules_mylang//mylang:repositories.bzl", "rules_mylang_dependencies")
+rules_mylang_dependencies()
+
+\`\`\`
+EOF

.gitignore

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+bazel-*
+.bazelrc.user

.pre-commit-config.yaml

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+# See CONTRIBUTING.md for instructions.
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+
+# Commitizen runs in commit-msg stage
+# but we don't want to run the other hooks on commit messages
+default_stages: [commit]
+
+repos:
+  # Check formatting and lint for starlark code
+  - repo: https://github.com/keith/pre-commit-buildifier
+    rev: 4.0.1.1
+    hooks:
+      - id: buildifier
+      - id: buildifier-lint
+  # Enforce that commit messages allow for later changelog generation
+  - repo: https://github.com/commitizen-tools/commitizen
+    rev: v2.18.0
+    hooks:
+      # Requires that commitizen is already installed
+      - id: commitizen
+        stages: [commit-msg]
+  - repo: https://github.com/pre-commit/mirrors-prettier
+    rev: "v2.4.0"
+    hooks:
+      - id: prettier

.prettierignore

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+docs/*.md

BUILD.bazel

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+load("@bazel_skylib//:bzl_library.bzl", "bzl_library")
+load("@bazel_gazelle//:def.bzl", "gazelle", "gazelle_binary")
+
+gazelle_binary(
+    name = "gazelle_bin",
+    languages = ["@bazel_skylib//gazelle/bzl"],
+)
+
+gazelle(
+    name = "gazelle",
+    gazelle = "gazelle_bin",
+)
+
+bzl_library(
+    name = "internal_deps",
+    srcs = ["internal_deps.bzl"],
+    visibility = ["//visibility:public"],
+    deps = [
+        "@bazel_tools//tools/build_defs/repo:http.bzl",
+        "@bazel_tools//tools/build_defs/repo:utils.bzl",
+    ],
+)

CONTRIBUTING.md

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+# How to Contribute
+
+## Formatting
+
+Starlark files should be formatted by buildifier.
+We suggest using a pre-commit hook to automate this.
+First [install pre-commit](https://pre-commit.com/#installation),
+then run
+
+```shell
+pre-commit install
+```
+
+Otherwise later tooling on CI may yell at you about formatting/linting violations.
+
+## Updating BUILD files
+
+Some targets are generated from sources.
+Currently this is just the `bzl_library` targets.
+Run `bazel run //:gazelle` to keep them up-to-date.
+
+## Using this as a development dependency of other rules
+
+You'll commonly find that you develop in another WORKSPACE, such as
+some other ruleset that depends on rules_mylang, or in a nested
+WORKSPACE in the integration_tests folder.
+
+To always tell Bazel to use this directory rather than some release
+artifact or a version fetched from the internet, run this from this
+directory:
+
+```sh
+OVERRIDE="--override_repository=rules_mylang=$(pwd)/rules_mylang"
+echo "build $OVERRIDE" >> ~/.bazelrc
+echo "fetch $OVERRIDE" >> ~/.bazelrc
+echo "query $OVERRIDE" >> ~/.bazelrc
+```
+
+This means that any usage of `@rules_mylang` on your system will point to this folder.
+
+## Releasing
+
+1. Determine the next release version, following semver (could automate in the future from changelog)
+1. Tag the repo and push it (or create a tag in GH UI)
+1. Watch the automation run on GitHub actions