1 files changed, 109 insertions, 0 deletions
diff --git a/src/gen/paths.rs b/src/gen/paths.rs
new file mode 100644
index 0000000..2bc958d
--- /dev/null
+++ b/src/gen/paths.rs
@@ -0,0 +1,109 @@
+use crate::gen::inside::protobuf_crate_path;
+use crate::gen::rust::ident::RustIdent;
+use crate::gen::rust::path::RustPath;
+use crate::gen::strx;
+use crate::gen::well_known_types::WELL_KNOWN_TYPES_PROTO_FILE_FULL_NAMES;
+use crate::Customize;
+
+// Copy-pasted from libsyntax.
+fn ident_start(c: char) -> bool {
+    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_'
+}
+
+// Copy-pasted from libsyntax.
+fn ident_continue(c: char) -> bool {
+    (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_'
+}
+
+pub(crate) fn proto_path_to_rust_mod(path: &str) -> RustIdent {
+    let without_dir = strx::remove_to(path, std::path::is_separator);
+    let without_suffix = strx::remove_suffix(without_dir, ".proto");
+
+    let name = without_suffix
+        .chars()
+        .enumerate()
+        .map(|(i, c)| {
+            let valid = if i == 0 {
+                ident_start(c)
+            } else {
+                ident_continue(c)
+            };
+            if valid {
+                c
+            } else {
+                '_'
+            }
+        })
+        .collect::<String>();
+
+    RustIdent::new(&name)
+}
+
+/// Used in protobuf-codegen-identical-test
+pub fn proto_name_to_rs(proto_file_path: &str) -> String {
+    format!("{}.rs", proto_path_to_rust_mod(proto_file_path))
+}
+
+pub(crate) fn proto_path_to_fn_file_descriptor(
+    proto_path: &str,
+    customize: &Customize,
+) -> RustPath {
+    let protobuf_crate = protobuf_crate_path(customize);
+    match proto_path {
+        "rustproto.proto" => protobuf_crate.append("rustproto::file_descriptor".into()),
+        "google/protobuf/descriptor.proto" => {
+            protobuf_crate.append("descriptor::file_descriptor".into())
+        }
+        s if WELL_KNOWN_TYPES_PROTO_FILE_FULL_NAMES.contains(&s) => protobuf_crate
+            .append_ident("well_known_types".into())
+            .append_ident(proto_path_to_rust_mod(s))
+            .append_ident("file_descriptor".into()),
+        s => RustPath::super_path()
+            .append_ident(proto_path_to_rust_mod(s))
+            .append_ident("file_descriptor".into()),
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::proto_path_to_rust_mod;
+    use crate::gen::rust::ident::RustIdent;
+
+    #[test]
+    fn test_mod_path_proto_ext() {
+        assert_eq!(
+            RustIdent::from("proto"),
+            proto_path_to_rust_mod("proto.proto")
+        );
+    }
+
+    #[test]
+    fn test_mod_path_unknown_ext() {
+        assert_eq!(
+            RustIdent::from("proto_proto3"),
+            proto_path_to_rust_mod("proto.proto3")
+        );
+    }
+
+    #[test]
+    fn test_mod_path_empty_ext() {
+        assert_eq!(RustIdent::from("proto"), proto_path_to_rust_mod("proto"));
+    }
+
+    #[test]
+    fn test_mod_path_dir() {
+        assert_eq!(
+            RustIdent::from("baz"),
+            proto_path_to_rust_mod("foo/bar/baz.proto"),
+        )
+    }
+
+    #[cfg(target_os = "windows")]
+    #[test]
+    fn test_mod_path_dir_backslashes() {
+        assert_eq!(
+            RustIdent::from("baz"),
+            proto_path_to_rust_mod("foo\\bar\\baz.proto"),
+        )
+    }
+}