Add rustfmt_skip to generated files

implementations/rust/preserves-schema/Makefile

@@ -5,5 +5,6 @@ regenerate:
 	cargo run -- \
 		--prefix crate::gen \
 		--support-crate crate \
+		--rustfmt-skip \
 		-o $(CURDIR)/src/gen \
 		../../../schema/schema.bin

implementations/rust/preserves-schema/src/bin/preserves-schema-rs.rs

@@ -22,6 +22,9 @@ struct CommandLine {
     #[structopt(long)]
     xref: Vec<String>,
 
+    #[structopt(long)]
+    rustfmt_skip: bool,
+
     input_glob: Vec<String>,
 }
 
@@ -43,6 +46,7 @@ fn main() -> Result<(), Error> {
     if let Some(c) = args.support_crate {
         config.support_crate = c;
     }
+    config.rustfmt_skip = args.rustfmt_skip;
     config.load_schemas_and_bundles(
         &expand_inputs(&args.input_glob)?,
         &expand_inputs(&args.xref)?)?;

implementations/rust/preserves-schema/src/compiler/mod.rs

@@ -104,6 +104,7 @@ pub struct CompilerConfig {
     pub support_crate: String,
     pub external_modules: Map<ModulePath, ExternalModule>,
     pub plugins: Vec<Box<dyn Plugin>>,
+    pub rustfmt_skip: bool,
 }
 
 pub fn load_schema_or_bundle_with_purpose(
@@ -189,6 +190,7 @@ impl CompilerConfig {
                 Box::new(parsers::ParserPlugin),
                 Box::new(unparsers::UnparserPlugin),
             ],
+            rustfmt_skip: false,
         }
     }
 
@@ -319,7 +321,11 @@ pub fn compile(config: &CompilerConfig) -> io::Result<()> {
 
         lines.push(Formatter::to_string(vertical(false, seq![
             "#![allow(unused_parens)]",
-            "#![allow(unused_imports)]",
+            "#![allow(unused_imports)]"])));
+        if config.rustfmt_skip {
+            lines.push("#![cfg_attr(rustfmt, rustfmt_skip)]".to_owned());
+        }
+        lines.push(Formatter::to_string(vertical(false, seq![
             "",
             "use std::convert::TryFrom;",
             format!("use {}::support as _support;", &config.support_crate),
@@ -352,6 +358,11 @@ pub fn compile(config: &CompilerConfig) -> io::Result<()> {
         mod_rs.extend(vec!["mod.rs"]);
         let mut lines = Vec::new();
 
+        if config.rustfmt_skip {
+            lines.push("#![cfg_attr(rustfmt, rustfmt_skip)]".to_owned());
+            lines.push("".to_owned());
+        }
+
         for (modpath, (_, module_purpose)) in config.bundle.iter() {
             if *module_purpose != Purpose::Codegen {
                 continue;

implementations/rust/preserves-schema/src/gen/mod.rs

@@ -1,3 +1,5 @@
+#![cfg_attr(rustfmt, rustfmt_skip)]
+
 pub mod schema;
 
 use crate::support as _support;

implementations/rust/preserves-schema/src/gen/schema.rs

@@ -1,5 +1,6 @@
 #![allow(unused_parens)]
 #![allow(unused_imports)]
+#![cfg_attr(rustfmt, rustfmt_skip)]
 
 use std::convert::TryFrom;
 use crate::support as _support;