various updates

This commit updated with some important feedback from @dtolnay. Thank
you!

.buckconfig

@@ -12,3 +12,6 @@ buck = none
 
 [parser]
 target_platform_detector_spec = target:root//...->prelude//platforms:default
+
+[project]
+ignore = .git, target

.github/workflows/ci.yml

@@ -0,0 +1,72 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches: [main]
+
+jobs:
+  test:
+    name: ${{matrix.name || format('Rust {0}', matrix.rust)}}
+    runs-on: ${{matrix.os || 'ubuntu'}}-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - rust: nightly
+          - rust: beta
+          - rust: stable
+          - rust: 1.69.0
+          - name: Cargo on macOS
+            rust: nightly
+            os: macos
+          - name: Cargo on Windows (msvc)
+            rust: nightly-x86_64-pc-windows-msvc
+            os: windows
+    steps:
+      - uses: actions/checkout@v3
+      - uses: dtolnay/rust-toolchain@master
+        with:
+          toolchain: ${{matrix.rust}}
+      - run: cargo check
+      - run: cargo run
+
+  buck:
+    name: Buck2 on ${{matrix.os == 'ubuntu' && 'Linux' || matrix.os == 'macos' && 'macOS' || matrix.os == 'windows' && 'Windows' || '???'}}
+    runs-on: ${{matrix.os}}-latest
+    if: github.event_name != 'pull_request'
+    strategy:
+      matrix:
+        os: [ubuntu, macos, windows]
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          submodules: true
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          components: rust-src
+      - uses: dtolnay/install-buck2@latest
+      - run: buck2 build ...
+      - run: buck2 run //src/bin:hello_world
+
+      - uses: actions/cache/restore@v3
+        id: cache
+        with:
+          path: ~/.cargo/bin/reindeer${{matrix.os == 'windows' && '.exe' || ''}}
+          key: ${{matrix.os}}-reindeer
+
+      - run: cargo install --git https://github.com/facebookincubator/reindeer reindeer
+        if: steps.cache.outputs.cache-hit != 'true'
+
+      - uses: actions/cache/save@v3
+        if: steps.cache.outputs.cache-hit != 'true'
+        with:
+          path: ~/.cargo/bin/reindeer${{matrix.os == 'windows' && '.exe' || ''}}
+          key: ${{steps.cache.outputs.cache-primary-key}}
+
+      - run: reindeer buckify
+        working-directory: third-party
+        if: matrix.os == 'ubuntu'
+      - name: Check reindeer-generated BUCK file up to date
+        run: git diff --exit-code
+        if: matrix.os == 'ubuntu'

.gitignore

@@ -1,2 +1,2 @@
-buck-out
+/buck-out
 target

Cargo.toml

@@ -5,3 +5,6 @@ edition = "2021"
 
 [lib]
 path = "src/lib/print_hello.rs"
+
+[dependencies]
+semver = "1.0.17"

src/bin/BUCK

@@ -5,4 +5,5 @@ rust_binary(
     deps = [
         "//third-party:semver",
     ],
+    visibility = ["PUBLIC"],
 )

third-party/BUCK

@@ -1,3 +1,6 @@
+load("@prelude//rust:cargo_buildscript.bzl", "buildscript_run")
+load("@prelude//rust:cargo_package.bzl", "cargo")
+
 alias(
     name = "semver",
     actual = ":semver-1.0.17",
@@ -12,7 +15,7 @@ http_archive(
     visibility = [],
 )
 
-rust_library(
+cargo.rust_library(
     name = "semver-1.0.17",
     srcs = [":semver-1.0.17.crate"],
     crate = "semver",
@@ -24,16 +27,3 @@ rust_library(
     ],
     visibility = [],
 )
-
-rust_binary(
-    name = "semver-1.0.17-build-script-build",
-    srcs = [":semver-1.0.17.crate"],
-    crate = "build_script_build",
-    crate_root = "semver-1.0.17.crate/build.rs",
-    edition = "2018",
-    features = [
-        "default",
-        "std",
-    ],
-    visibility = [],
-)

toolchains/BUCK

@@ -16,7 +16,6 @@ system_rust_toolchain(
 
 system_cxx_toolchain(
     name = "cxx",
-    linker = "link.exe",
     visibility = ["PUBLIC"],
 )