fix tokio-rs#1001 and add tests

prost-build/src/lib.rs

@@ -1174,6 +1174,25 @@ impl Config {
         let mut written = 0;
         entries.sort();
 
+        if depth == 0 {
+            let (empty, remaining): (Vec<&Module>, Vec<&Module>) =
+                entries.into_iter().partition(|m| m.is_empty());
+            for module in empty {
+                let modname = module.to_partial_file_name(..=depth);
+                if basepath.is_some() {
+                    self.write_line(outfile, depth, &format!("include!(\"{}.rs\");", modname))?;
+                } else {
+                    self.write_line(
+                        outfile,
+                        depth,
+                        &format!("include!(concat!(env!(\"OUT_DIR\"), \"/{}.rs\"));", modname),
+                    )?;
+                }
+                written += 1;
+            }
+            entries = remaining;
+        }
+
         while !entries.is_empty() {
             let modident = entries[0].part(depth);
             let matching: Vec<&Module> = entries
@@ -1414,7 +1433,11 @@ impl Module {
     }
 
     fn to_partial_file_name(&self, range: RangeToInclusive<usize>) -> String {
-        self.components[range].join(".")
+        if self.components.is_empty() {
+            "_".to_string()
+        } else {
+            self.components[range].join(".")
+        }
     }
 
     fn part(&self, idx: usize) -> &str {

tests/src/build.rs

@@ -146,6 +146,35 @@ fn main() {
         .compile_protos(&[src.join("well_known_types.proto")], includes)
         .unwrap();
 
+    {
+        let out = std::env::var("OUT_DIR").unwrap();
+        let out_path = PathBuf::from(out).join("no_package");
+
+        std::fs::create_dir_all(&out_path).unwrap();
+
+        prost_build::Config::new()
+            .out_dir(out_path)
+            .include_file("_includes.rs")
+            .compile_protos(&[src.join("no_package_with_message.proto")], includes)
+            .unwrap();
+    }
+
+    {
+        let out = std::env::var("OUT_DIR").unwrap();
+        let out_path = PathBuf::from(out).join("complex_package_structure");
+
+        std::fs::create_dir_all(&out_path).unwrap();
+
+        prost_build::Config::new()
+            .out_dir(out_path)
+            .include_file("__.rs")
+            .compile_protos(
+                &[src.join("complex_package_structure/proto/post/post.proto")],
+                &[src.join("complex_package_structure/proto")],
+            )
+            .unwrap();
+    }
+
     config
         .compile_protos(
             &[src.join("packages/widget_factory.proto")],

tests/src/complex_package_structure/mod.rs

@@ -0,0 +1,61 @@
+use self::proto::image::Image;
+use self::proto::post::content::post_content_fragment;
+use self::proto::post::content::PostContentFragment;
+use self::proto::post::Post;
+use self::proto::user::User;
+use self::proto::Timestamp;
+
+mod proto {
+    include!(concat!(env!("OUT_DIR"), "/complex_package_structure/__.rs"));
+}
+
+#[test]
+fn it_works() {
+    let user = User {
+        id: "69a4cd96-b956-4fb1-9a97-b222eac33b8a".to_string(),
+        name: "Test User".to_string(),
+        created_at: Some(Timestamp {
+            seconds: 1710366135,
+            nanos: 0,
+        }),
+        ..User::default()
+    };
+    let posts = vec![
+        Post::default(),
+        Post {
+            id: "aa1e751f-e287-4c6e-aa0f-f838f96a1a60".to_string(),
+            author: Some(user),
+            content: vec![
+                PostContentFragment {
+                    content: Some(post_content_fragment::Content::Text(
+                        "Hello, world!".to_string(),
+                    )),
+                },
+                PostContentFragment {
+                    content: Some(post_content_fragment::Content::Image(Image {
+                        name: "doggo.jpg".to_string(),
+                        description: Some("A dog".to_string()),
+                        data: vec![0, 1, 2, 3],
+                    })),
+                },
+                PostContentFragment {
+                    content: Some(post_content_fragment::Content::Link(
+                        "https://example.com".to_string(),
+                    )),
+                },
+            ],
+            ..Post::default()
+        },
+        Post::default(),
+    ];
+    assert_eq!(posts.len(), 3);
+    assert_eq!(posts[1].content.len(), 3);
+    if let PostContentFragment {
+        content: Some(post_content_fragment::Content::Image(Image { name, .. })),
+    } = &posts[1].content[1]
+    {
+        assert_eq!(name, "doggo.jpg");
+    } else {
+        assert!(false, "Expected an image")
+    }
+}

tests/src/complex_package_structure/proto/.editorconfig

@@ -0,0 +1,3 @@
+[*]
+ij_protobuf_keep_blank_lines_in_code = 0
+insert_final_newline = true

tests/src/complex_package_structure/proto/post/content.proto

@@ -0,0 +1,13 @@
+syntax = "proto3";
+
+package post.content;
+
+import "wrong/image.proto";
+
+message PostContentFragment {
+  oneof content {
+    string text = 1;
+    image.Image image = 2;
+    string link = 3;
+  }
+}

tests/src/complex_package_structure/proto/post/post.proto

@@ -0,0 +1,17 @@
+syntax = "proto3";
+
+package post;
+
+import "std/time.proto";
+import "user/user.proto";
+import "post/content.proto";
+
+message Post {
+  string id = 1;
+  string title = 2;
+  reserved 3;
+  user.User author = 4;
+  Timestamp created_at = 5;
+  Timestamp updated_at = 6;
+  repeated content.PostContentFragment content = 7;
+}

tests/src/complex_package_structure/proto/std/time.proto

@@ -0,0 +1,6 @@
+syntax = "proto3";
+
+message Timestamp {
+  int64 seconds = 1;
+  int32 nanos = 2;
+}

tests/src/complex_package_structure/proto/user/user.proto

@@ -0,0 +1,13 @@
+syntax = "proto3";
+
+package user;
+
+import "std/time.proto";
+
+message User {
+  string id = 1;
+  Timestamp created_at = 2;
+  Timestamp updated_at = 3;
+  string name = 4;
+  string email = 5;
+}

tests/src/complex_package_structure/proto/wrong/image.proto

@@ -0,0 +1,12 @@
+// This file makes sure that the file path of the proto file has nothing to do with the package name,
+// therefore testing the validity of write_includes.
+
+syntax = "proto3";
+
+package image;
+
+message Image {
+  string name = 1;
+  optional string description = 2;
+  bytes data = 3;
+}

tests/src/lib.rs

@@ -33,6 +33,8 @@ pub mod unittest;
 #[cfg(test)]
 mod bootstrap;
 #[cfg(test)]
+mod complex_package_structure;
+#[cfg(test)]
 mod debug;
 #[cfg(test)]
 mod deprecated_field;
@@ -41,6 +43,8 @@ mod generic_derive;
 #[cfg(test)]
 mod message_encoding;
 #[cfg(test)]
+mod no_package_with_message;
+#[cfg(test)]
 mod no_unused_results;
 #[cfg(test)]
 #[cfg(feature = "std")]

tests/src/no_package_with_message.proto

@@ -0,0 +1,5 @@
+syntax = "proto3";
+
+message NoPackageWithMessageExampleMsg {
+  string some_field = 1;
+}

tests/src/no_package_with_message.rs

@@ -0,0 +1,11 @@
+mod proto {
+    include!(concat!(env!("OUT_DIR"), "/no_package/_includes.rs"));
+}
+
+#[test]
+fn it_works() {
+    assert_eq!(
+        proto::NoPackageWithMessageExampleMsg::default(),
+        proto::NoPackageWithMessageExampleMsg::default()
+    );
+}