Improve output code formatting

Author: twistedfall

binding-generator/src/string_ext.rs

@@ -25,7 +25,7 @@ pub trait StringExt {
 	) -> bool;
 	fn extend_join(&mut self, it: impl Iterator<Item = impl AsRef<str>>, sep: &str);
 	fn extend_sep(&mut self, sep: &str, s: &str);
-	fn push_indented_str(&mut self, indent: Indent, val: &str);
+	fn push_indented_lines(&mut self, indent: Indent, val: &str);
 	fn bump_counter(&mut self);
 	fn cleanup_name(&mut self);
 }
@@ -211,13 +211,16 @@ impl StringExt for String {
 		self.push_str(s);
 	}
 
-	fn push_indented_str(&mut self, indent: Indent, val: &str) {
+	fn push_indented_lines(&mut self, indent: Indent, val: &str) {
 		let mut lines = val.lines_with_nl();
 		if let Some(line) = lines.next() {
 			self.push_str(line);
 		}
 		for line in lines {
-			self.extend(iter::repeat(indent.symbol).take(indent.len));
+			// there is more than just a newline in the buffer
+			if line.len() > 1 {
+				self.extend(iter::repeat(indent.symbol).take(indent.len));
+			}
 			self.push_str(line);
 		}
 	}
@@ -346,7 +349,7 @@ impl CompiledInterpolation<'_> {
 				}
 				Compiled::IntpLiteral(s) => out += s,
 				Compiled::Var(name) => {
-					out.push_indented_str(line_indent, params.get(name).map_or(INVALID_PARAM_NAME, |x| x.as_ref()))
+					out.push_indented_lines(line_indent, params.get(name).map_or(INVALID_PARAM_NAME, |x| x.as_ref()))
 				}
 				Compiled::IntpLineEnd(s) => {
 					out += s;

binding-generator/src/test.rs

@@ -372,6 +372,26 @@ test3 end
 			.interpolate(&HashMap::from([("name1", ""), ("name2", "test2"), ("name3", "test3")]));
 		assert_eq!("	test2 			test3", res);
 	}
+
+	// empty lines don't get indent
+	{
+		let tpl = "
+block {
+	{{var}}
+}";
+		let var = "\
+line1
+
+line2";
+		let expected = "\
+block {
+	line1
+
+	line2
+}";
+		let res = tpl.compile_interpolation().interpolate(&HashMap::from([("var", var)]));
+		assert_eq!(expected, res);
+	}
 }
 
 #[test]

binding-generator/src/writer/rust_native/comment.rs

@@ -234,7 +234,10 @@ fn add_comment_markers<'c>(comment: &'c str, marker: &str) -> Cow<'c, str> {
 				String::with_capacity(comment.len() + (marker.len() + 1) * 128),
 				|mut out_prefixed, line| {
 					out_prefixed.push_str(marker);
-					out_prefixed.push(' ');
+					// there is more than just a newline in the buffer
+					if line.len() > 1 {
+						out_prefixed.push(' ');
+					}
 					out_prefixed + line
 				},
 			)

binding-generator/src/writer/rust_native/mod.rs

@@ -165,13 +165,12 @@ impl GeneratorVisitor<'_> for RustNativeBindingWriter<'_> {
 	fn visit_class(&mut self, class: Class) {
 		self.emit_debug_log(&class);
 		if class.kind().is_trait() {
-			self.prelude_traits.push(format!(
-				"super::{}",
-				class.rust_trait_name(NameStyle::decl(), Constness::Const)
-			));
 			self
 				.prelude_traits
-				.push(format!("super::{}", class.rust_trait_name(NameStyle::decl(), Constness::Mut)));
+				.push(class.rust_trait_name(NameStyle::decl(), Constness::Const).into_owned());
+			self
+				.prelude_traits
+				.push(class.rust_trait_name(NameStyle::decl(), Constness::Mut).into_owned());
 		}
 		let name = class.cpp_name(CppNameStyle::Reference).into_owned();
 		self.rust_classes.push((name.clone(), class.gen_rust(self.opencv_version)));
@@ -216,7 +215,7 @@ impl GeneratorVisitor<'_> for RustNativeBindingWriter<'_> {
 		write_generated_type(&self.types_dir, "cpp", prio, &safe_id, || typ.gen_cpp());
 	}
 
-	fn goodbye(self) {
+	fn goodbye(mut self) {
 		static RUST: Lazy<CompiledInterpolation> = Lazy::new(|| include_str!("tpl/module/rust.tpl.rs").compile_interpolation());
 
 		static RUST_PRELUDE: Lazy<CompiledInterpolation> =
@@ -230,7 +229,13 @@ impl GeneratorVisitor<'_> for RustNativeBindingWriter<'_> {
 		insert_lines(&mut rust, self.rust_typedefs.into_iter().collect());
 		insert_lines(&mut rust, self.rust_funcs);
 		insert_lines(&mut rust, self.rust_classes);
-		let prelude = RUST_PRELUDE.interpolate(&HashMap::from([("traits", self.prelude_traits.join(", "))]));
+		let pub_use_traits = if self.prelude_traits.is_empty() {
+			"".to_string()
+		} else {
+			self.prelude_traits.sort_unstable();
+			format!("pub use super::{{{}}};", self.prelude_traits.join(", "))
+		};
+		let prelude = RUST_PRELUDE.interpolate(&HashMap::from([("pub_use_traits", pub_use_traits)]));
 		let comment = RenderComment::new(&self.comment, self.opencv_version);
 		let comment = comment.render_with_comment_marker("//!");
 		File::create(&self.rust_path)

binding-generator/src/writer/rust_native/tpl/class/boxed.tpl.rs

@@ -1,7 +1,7 @@
 {{doc_comment}}
 {{debug}}
 pub struct {{rust_local}} {
-	ptr: {{rust_extern_mut}}
+	ptr: {{rust_extern_mut}},
 }
 
 opencv_type_boxed! { {{rust_local}} }

binding-generator/src/writer/rust_native/tpl/module/prelude.tpl.rs

@@ -1,4 +1,3 @@
 pub mod prelude {
-	pub use { {{traits}} };
+	{{pub_use_traits}}
 }
-

binding-generator/src/writer/rust_native/tpl/module/rust.tpl.rs

@@ -1,5 +1,6 @@
 {{comment}}
-use crate::{mod_prelude::*, {{static_modules}}};
+use crate::mod_prelude::*;
+use crate::{{{static_modules}}};
 {{prelude}}
 
 {{code}}

build/generator/collector.rs

@@ -240,7 +240,10 @@ fn is_type_externs_file(path: &Path, module: &str) -> bool {
 fn copy_indent(mut read: impl BufRead, write: &mut impl Write, indent: &str) -> Result<()> {
 	let mut line = Vec::with_capacity(100);
 	while read.read_until(b'\n', &mut line)? != 0 {
-		write.write_all(indent.as_bytes())?;
+		// there is more than just a newline in the buffer
+		if line.len() > 1 {
+			write.write_all(indent.as_bytes())?;
+		}
 		write.write_all(&line)?;
 		line.clear();
 	}