*: add lite-runtime customization options

proto/rustproto.proto

@@ -35,6 +35,9 @@ extend google.protobuf.FileOptions {
     optional bool serde_derive_all = 17030;
     // Guard serde annotations with cfg attr.
     optional string serde_derive_cfg_all = 17031;
+
+    // When true, will only generate codes that works with lite runtime.
+    optional bool lite_runtime_all = 17035;
 }
 
 extend google.protobuf.MessageOptions {

protobuf-codegen/src/customize.rs

@@ -31,6 +31,8 @@ pub struct Customize {
     pub serde_derive: Option<bool>,
     /// When `serde_derive` is set, serde annotations will be guarded with `#[cfg(cfg, ...)]`.
     pub serde_derive_cfg: Option<String>,
+    /// Enable lite runtime
+    pub lite_runtime: Option<bool>,
 
     // When adding more options please keep in sync with `parse_from_parameter` below.
     /// Make sure `Customize` is always used with `..Default::default()`
@@ -83,6 +85,9 @@ impl Customize {
         if let Some(ref v) = that.serde_derive_cfg {
             self.serde_derive_cfg = Some(v.clone());
         }
+        if let Some(v) = that.lite_runtime {
+            self.lite_runtime = Some(v);
+        }
     }
 
     /// Update unset fields of self with fields from other customize
@@ -131,6 +136,8 @@ impl Customize {
                 r.serde_derive = Some(parse_bool(v)?);
             } else if n == "serde_derive_cfg" {
                 r.serde_derive_cfg = Some(v.to_owned());
+            } else if n == "lite_runtime" {
+                r.lite_runtime = Some(parse_bool(v)?);
             } else {
                 return Err(CustomizeParseParameterError::UnknownOptionName(
                     n.to_owned(),
@@ -153,6 +160,7 @@ pub fn customize_from_rustproto_for_message(source: &MessageOptions) -> Customiz
     let singular_field_option = rustproto::exts::singular_field_option.get(source);
     let serde_derive = rustproto::exts::serde_derive.get(source);
     let serde_derive_cfg = rustproto::exts::serde_derive_cfg.get(source);
+    let lite_runtime = None;
     Customize {
         expose_oneof,
         expose_fields,
@@ -165,6 +173,7 @@ pub fn customize_from_rustproto_for_message(source: &MessageOptions) -> Customiz
         singular_field_option,
         serde_derive,
         serde_derive_cfg,
+        lite_runtime,
         _future_options: (),
     }
 }
@@ -182,6 +191,7 @@ pub fn customize_from_rustproto_for_field(source: &FieldOptions) -> Customize {
     let singular_field_option = rustproto::exts::singular_field_option_field.get(source);
     let serde_derive = None;
     let serde_derive_cfg = None;
+    let lite_runtime = None;
     Customize {
         expose_oneof,
         expose_fields,
@@ -194,6 +204,7 @@ pub fn customize_from_rustproto_for_field(source: &FieldOptions) -> Customize {
         singular_field_option,
         serde_derive,
         serde_derive_cfg,
+        lite_runtime,
         _future_options: (),
     }
 }
@@ -210,6 +221,7 @@ pub fn customize_from_rustproto_for_file(source: &FileOptions) -> Customize {
     let singular_field_option = rustproto::exts::singular_field_option_all.get(source);
     let serde_derive = rustproto::exts::serde_derive_all.get(source);
     let serde_derive_cfg = rustproto::exts::serde_derive_cfg_all.get(source);
+    let lite_runtime = rustproto::exts::lite_runtime_all.get(source);
     Customize {
         expose_oneof,
         expose_fields,
@@ -222,6 +234,7 @@ pub fn customize_from_rustproto_for_file(source: &FileOptions) -> Customize {
         singular_field_option,
         serde_derive,
         serde_derive_cfg,
+        lite_runtime,
         _future_options: (),
     }
 }

protobuf-codegen/src/enums.rs

@@ -70,16 +70,19 @@ impl<'a> EnumGen<'a> {
                 root_scope,
             )
         };
-        EnumGen {
-            enum_with_scope,
-            type_name: rust_name,
-            lite_runtime: enum_with_scope
+        let lite_runtime = customize.lite_runtime.unwrap_or_else(|| {
+            enum_with_scope
                 .get_scope()
                 .get_file_descriptor()
                 .options
                 .get_message()
                 .get_optimize_for()
-                == FileOptions_OptimizeMode::LITE_RUNTIME,
+                == FileOptions_OptimizeMode::LITE_RUNTIME
+        });
+        EnumGen {
+            enum_with_scope,
+            type_name: rust_name,
+            lite_runtime,
             customize: customize.clone(),
         }
     }

protobuf-codegen/src/lib.rs

@@ -128,6 +128,13 @@ fn gen_file(
     let scope = FileScope {
         file_descriptor: file,
     }.to_scope();
+    let lite_runtime = customize.lite_runtime.unwrap_or_else(|| {
+        file
+            .options
+            .get_message()
+            .get_optimize_for()
+            == FileOptions_OptimizeMode::LITE_RUNTIME
+    });
 
     let mut v = Vec::new();
 
@@ -150,8 +157,7 @@ fn gen_file(
 
         write_extensions(file, &root_scope, &mut w);
 
-        let optimize_mode = file.options.get_message().get_optimize_for();
-        if optimize_mode != FileOptions_OptimizeMode::LITE_RUNTIME {
+        if !lite_runtime {
             w.write_line("");
             write_file_descriptor_data(file, &mut w);
         }

protobuf-codegen/src/message.rs

@@ -40,17 +40,20 @@ impl<'a> MessageGen<'a> {
             .into_iter()
             .map(|field| FieldGen::parse(field, root_scope, &customize))
             .collect();
+        let lite_runtime = customize.lite_runtime.unwrap_or_else(|| {
+            message
+                .get_file_descriptor()
+                .options
+                .get_message()
+                .get_optimize_for()
+                == FileOptions_OptimizeMode::LITE_RUNTIME
+        });
         MessageGen {
             message: message,
             root_scope: root_scope,
             type_name: message.rust_name(),
             fields: fields,
-            lite_runtime: message
-                .get_file_descriptor()
-                .options
-                .get_message()
-                .get_optimize_for()
-                == FileOptions_OptimizeMode::LITE_RUNTIME,
+            lite_runtime,
             customize,
         }
     }
@@ -73,7 +76,8 @@ impl<'a> MessageGen<'a> {
             .filter(|f| match f.kind {
                 FieldKind::Singular(ref singular) => singular.flag.is_required(),
                 _ => false,
-            }).collect()
+            })
+            .collect()
     }
 
     fn message_fields(&'a self) -> Vec<&'a FieldGen> {
@@ -415,11 +419,19 @@ impl<'a> MessageGen<'a> {
     }
 
     fn write_impl_default_for_amp(&self, w: &mut CodeWriter) {
-        w.impl_args_for_block(&["'a"], "::std::default::Default", &format!("&'a {}", self.type_name), |w| {
-            w.def_fn(&format!("default() -> &'a {}", self.type_name), |w| {
-                w.write_line(&format!("<{} as ::protobuf::Message>::default_instance()", self.type_name));
-            });
-        });
+        w.impl_args_for_block(
+            &["'a"],
+            "::std::default::Default",
+            &format!("&'a {}", self.type_name),
+            |w| {
+                w.def_fn(&format!("default() -> &'a {}", self.type_name), |w| {
+                    w.write_line(&format!(
+                        "<{} as ::protobuf::Message>::default_instance()",
+                        self.type_name
+                    ));
+                });
+            },
+        );
     }
 
     fn write_dummy_impl_partial_eq(&self, w: &mut CodeWriter) {

protobuf-test/src/common/v2/test_enable_lite_runtime.rs

@@ -0,0 +1,13 @@
+use protobuf_test_common::*;
+
+use super::test_enable_lite_runtime_pb::*;
+
+#[test]
+fn test_lite_runtime() {
+    let mut m = TestLiteRuntime::new();
+    m.set_v(10);
+    test_serialize_deserialize("08 0a", &m);
+
+    // test it doesn't crash
+    format!("{:?}", m);
+}

protobuf-test/src/common/v2/test_enable_lite_runtime_pb.proto

@@ -0,0 +1,18 @@
+syntax = "proto2";
+
+import "rustproto.proto";
+option (rustproto.generate_accessors_all) = true;
+option (rustproto.lite_runtime_all) = true;
+
+
+package test_enable_lite_runtime;
+
+enum EnumTestLiteRuntime {
+    UNKNOWN = 0;
+    ONE = 1;
+    TWO = 2;
+}
+
+message TestLiteRuntime {
+    optional int32 v = 1;
+}