Exclude protoc/test-protoc from default workspace

Because it depends on another crate binary, and Cargo does not
expose binaries from dependencies.

(rust-lang/cargo#4316)

Cargo.toml

@@ -1,7 +1,8 @@
 [workspace]
 members = [
     "protoc",
-    "protoc/test-protoc",
+    # Exclude test-protoc from the project, because it depends on binary
+    #"protoc/test-protoc",
     "protoc-rust",
     "protobuf",
     "protobuf-codegen",

ci/run.sh

@@ -19,9 +19,20 @@ protobuf-codegen-pure-test/test.sh
 protoc/test.sh
 cargo build --all --all-targets
 
+check_protoc_crate() {
+    # test depends on `protoc-gen-rust` binary, thus it cannot be a part of workspace
+    cargo build -p protobuf-codegen
+    (
+        cd protoc/test-protoc
+        cargo check
+    )
+}
+
 if [ -z "$ON_WINDOWS" ]; then
     cargo doc -p protobuf
     cargo doc -p protoc
+
+    check_protoc_crate
 fi
 
 # vim: set ts=4 sw=4 et:

protoc/test-protoc/Cargo.toml

@@ -1,3 +1,5 @@
+[workspace]
+
 [package]
 name = "test-protoc"
 version = "0.0.0"