doc: Show feature badges on docs.rs

Cargo.toml

@@ -27,3 +27,4 @@ raw_decoder = []
 
 [package.metadata.docs.rs]
 features = ["stream", "raw_decoder"]
+rustdoc-args = ["--cfg", "docsrs"]

src/decode/stream.rs

@@ -61,6 +61,7 @@ where
 
 /// Lzma decompressor that can process multiple chunks of data using the
 /// `io::Write` interface.
+#[cfg_attr(docsrs, doc(cfg(stream)))]
 pub struct Stream<W>
 where
     W: Write,

src/lib.rs

@@ -1,5 +1,5 @@
 //! Pure-Rust codecs for LZMA, LZMA2, and XZ.
-
+#![cfg_attr(docsrs, feature(doc_cfg, doc_cfg_hide))]
 #![deny(missing_docs)]
 #![deny(missing_debug_implementations)]
 #![forbid(unsafe_code)]
@@ -24,13 +24,17 @@ pub mod compress {
 /// Decompression helpers.
 pub mod decompress {
     pub use crate::decode::options::*;
+
     #[cfg(feature = "raw_decoder")]
+    #[cfg_attr(docsrs, doc(cfg(raw_decoder)))]
     pub mod raw {
         //! Raw decoding primitives for LZMA/LZMA2 streams.
         pub use crate::decode::lzma::{LzmaDecoder, LzmaParams, LzmaProperties};
         pub use crate::decode::lzma2::Lzma2Decoder;
     }
+
     #[cfg(feature = "stream")]
+    #[cfg_attr(docsrs, doc(cfg(stream)))]
     pub use crate::decode::stream::Stream;
 }