Use protoc from Bazel if missing from path

Closes #2134

Cargo.lock

@@ -118,6 +118,7 @@ dependencies = [
  "unicase",
  "unicode-normalization",
  "utime",
+ "which",
  "zip",
  "zstd",
 ]

cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",

pylib/rsbridge/cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",

rslib/BUILD.bazel

@@ -31,6 +31,7 @@ cargo_build_script(
     ],
     deps = [
         "//rslib/cargo:prost_build",
+        "//rslib/cargo:which",
     ],
 )
 

rslib/Cargo.toml

@@ -23,6 +23,7 @@ required-features = ["bench"]
 
 [build-dependencies]
 prost-build = "0.11.1"
+which = "4.3.0"
 
 [dev-dependencies]
 env_logger = "0.9.1"

rslib/build/protobuf.rs

@@ -1,7 +1,11 @@
 // Copyright: Ankitects Pty Ltd and contributors
 // License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
 
-use std::{env, fmt::Write, path::PathBuf};
+use std::{
+    env,
+    fmt::Write,
+    path::{Path, PathBuf},
+};
 
 struct CustomGenerator {}
 
@@ -71,6 +75,7 @@ fn service_generator() -> Box<dyn prost_build::ServiceGenerator> {
 }
 
 pub fn write_backend_proto_rs() {
+    maybe_add_protobuf_to_path();
     let proto_dir = if let Ok(proto) = env::var("PROTO_TOP") {
         PathBuf::from(proto).parent().unwrap().to_owned()
     } else {
@@ -122,3 +127,24 @@ pub fn write_backend_proto_rs() {
         .compile_protos(paths.as_slice(), &[proto_dir])
         .unwrap();
 }
+
+/// If PROTOC is not defined, and protoc is not on path, use the protoc
+/// fetched by Bazel so that Rust Analyzer does not fail.
+fn maybe_add_protobuf_to_path() {
+    if std::env::var("PROTOC").is_ok() {
+        return;
+    }
+    if which::which("protoc").is_ok() {
+        return;
+    }
+    let base = Path::new("../.bazel/out/../external");
+    let subpath = if cfg!(target_os = "windows") {
+        "protoc_bin_windows/bin/protoc.exe"
+    } else if cfg!(target_os = "macos") {
+        "protoc_bin_macos/bin/protoc"
+    } else {
+        "protoc_bin_linux_x86_64/bin/protoc"
+    };
+    let path = base.join(subpath);
+    std::env::set_var("PROTOC", path.to_str().unwrap());
+}

rslib/cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",

rslib/i18n/cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",

rslib/i18n_helpers/cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",

rslib/linkchecker/cargo/BUILD.bazel

@@ -579,6 +579,15 @@ alias(
     ],
 )
 
+alias(
+    name = "which",
+    actual = "@raze__which__4_3_0//:which",
+    tags = [
+        "cargo-raze",
+        "manual",
+    ],
+)
+
 alias(
     name = "zip",
     actual = "@raze__zip__0_6_2//:zip",