Turn the no_std feature into default-enabled std

.github/workflows/ci.yml

@@ -11,6 +11,7 @@ jobs:
     strategy:
       matrix:
         toolchain: [stable, beta, nightly]
+        features: [--no-default-features, --all-features]
     steps:
       - name: Checkout sources
         uses: actions/checkout@v1
@@ -26,14 +27,49 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: check
-          args: --all-features --all
+          args: ${{ matrix.features }} --workspace
+
+  no-std:
+    name: no_std Check
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout sources
+        uses: actions/checkout@v1
+
+      - name: Install nightly toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          override: true
+
+      - name: Install cargo no-std-check
+        uses: actions-rs/cargo@v1
+        with:
+          command: install
+          args: cargo-no-std-check
+
+      # https://github.com/mystor/cargo-no-std-check/issues/2
+      # `--no-default-features` doesn't work with `--workspace` correctly.
+      - name: Run cargo no-std-check on libflate crate
+        uses: actions-rs/cargo@v1
+        with:
+          command: no-std-check
+          args: --no-default-features
+
+      - name: Run cargo no-std-check on libflate_lz77 crate
+        uses: actions-rs/cargo@v1
+        with:
+          command: no-std-check
+          args: --no-default-features --manifest-path libflate_lz77/Cargo.toml
 
   test:
     name: Test Suite
     runs-on: ubuntu-latest
     strategy:
       matrix:
         toolchain: [stable, beta, nightly]
+        features: [--no-default-features, --all-features]
     steps:
       - name: Checkout sources
         uses: actions/checkout@v1
@@ -49,14 +85,15 @@ jobs:
         uses: actions-rs/cargo@v1
         with:
           command: test
-          args: --all-features --all
+          args: ${{ matrix.features }} --workspace
 
   lints:
     name: Lints
     runs-on: ubuntu-latest
     strategy:
       matrix:
         toolchain: [stable, beta, nightly]
+        features: [--no-default-features, --all-features]
     steps:
       - name: Checkout sources
         uses: actions/checkout@v1
@@ -75,21 +112,9 @@ jobs:
           command: fmt
           args: --all -- --check
 
-      - name: Run cargo clippy
-        if: matrix.toolchain == 'beta'
-        uses: actions-rs/cargo@v1
-        with:
-          command: clippy
-          # As `return_self_not_must_use` became `pedantic` in the 1.60.0-nightly channel,
-          # we allow the warning to avoid unnecessary code fixes.
-          # See: https://github.com/rust-lang/rust-clippy/issues/8197
-          #
-          # TODO: Remove this branch once stable-1.59.0 is released.
-          args: --all-features --all -- -D warnings --allow clippy::return_self_not_must_use
-
       - name: Run cargo clippy
         if: matrix.toolchain != 'beta'
         uses: actions-rs/cargo@v1
         with:
           command: clippy
-          args: --all-features --all -- -D warnings
+          args: ${{ matrix.features }} --workspace -- -D warnings

Cargo.toml

@@ -1,27 +1,29 @@
 [package]
 name = "libflate"
-version = "1.4.0"
+version = "2.0.0"
 authors = ["Takeru Ohta <phjgt308@gmail.com>"]
 description = "A Rust implementation of DEFLATE algorithm and related formats (ZLIB, GZIP)"
 homepage = "https://github.com/sile/libflate"
 repository = "https://github.com/sile/libflate"
 readme = "README.md"
 keywords = ["deflate", "gzip", "zlib"]
-categories = ["compression"]
+categories = ["compression", "no-std"]
 license = "MIT"
 edition = "2018"
 
 [badges]
 coveralls = {repository = "sile/libflate"}
 
 [dependencies]
-adler32 = "1"
-crc32fast = "1.1.1"
-libflate_lz77 = { path = "libflate_lz77", version = "1.1", default_features = false }
-core2 = { version = "0.4", default_features = false, features = ["alloc"], optional = true }
+adler32 = { version = "1", default-features = false }
+crc32fast = { version = "1.1.1", default-features = false }
+dary_heap = "0.3.5"
+libflate_lz77 = { path = "libflate_lz77", version = "2.0.0", default-features = false }
+core2 = { version = "0.4", default-features = false, features = ["alloc"] }
 
 [features]
-no_std = ["libflate_lz77/no_std", "core2"]
+default = ["std"]
+std = ["libflate_lz77/std", "core2/std"]
 
 [dev-dependencies]
 clap = "2"

examples/flate.rs

@@ -1,32 +1,24 @@
+#![cfg_attr(not(feature = "std"), no_std)]
+
 extern crate clap;
 extern crate libflate;
 
-#[cfg(not(feature = "no_std"))]
-use clap::App;
-#[cfg(not(feature = "no_std"))]
-use clap::Arg;
-#[cfg(not(feature = "no_std"))]
-use clap::SubCommand;
-#[cfg(not(feature = "no_std"))]
-use libflate::gzip;
-#[cfg(not(feature = "no_std"))]
-use libflate::zlib;
-#[cfg(not(feature = "no_std"))]
-use std::fs;
-#[cfg(not(feature = "no_std"))]
-use std::io;
-#[cfg(not(feature = "no_std"))]
-use std::io::Read;
-#[cfg(not(feature = "no_std"))]
-use std::io::Write;
-#[cfg(not(feature = "no_std"))]
-use std::process;
-
-#[cfg(feature = "no_std")]
+#[cfg(not(feature = "std"))]
 fn main() {}
 
-#[cfg(not(feature = "no_std"))]
+#[cfg(feature = "std")]
 fn main() {
+    use clap::App;
+    use clap::Arg;
+    use clap::SubCommand;
+    use libflate::gzip;
+    use libflate::zlib;
+    use std::fs;
+    use std::io;
+    use std::io::Read;
+    use std::io::Write;
+    use std::process;
+
     let matches = App::new("deflate")
         .arg(
             Arg::with_name("INPUT")

libflate_lz77/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "libflate_lz77"
-version = "1.2.0"
+version = "2.0.0"
 authors = ["Takeru Ohta <phjgt308@gmail.com>"]
 edition = "2018"
 description = "LZ77 encoder for libflate crate"
@@ -16,11 +16,12 @@ coveralls = {repository = "sile/libflate"}
 
 [dependencies]
 rle-decode-fast = "1.0.0"
-core2 = { version = "0.4", default-features = false, features = ["alloc"], optional = true }
-hashbrown = { version = "0.13", optional = true }
+core2 = { version = "0.4", default-features = false, features = ["alloc"] }
+hashbrown = { version = "0.13" }
 
 [dev-dependencies]
-libflate = { path = "../", version = "1" }
+libflate = { path = "../", version = "2.0", default-features = false }
 
 [features]
-no_std = ["core2", "hashbrown"]
+default = ["std"]
+std = ["core2/std", "libflate/std"]

libflate_lz77/src/default.rs

@@ -1,11 +1,9 @@
-#[cfg(feature = "no_std")]
 use alloc::vec::Vec;
-#[cfg(feature = "no_std")]
 use core::cmp;
-#[cfg(feature = "no_std")]
+#[cfg(not(feature = "std"))]
 use hashbrown::HashMap;
-#[cfg(not(feature = "no_std"))]
-use std::{cmp, collections::HashMap};
+#[cfg(feature = "std")]
+use std::collections::HashMap;
 
 use super::Code;
 use super::Lz77Encode;

libflate_lz77/src/lib.rs

@@ -2,19 +2,15 @@
 //!
 //! LZ77 is a compression algorithm used in [DEFLATE](https://tools.ietf.org/html/rfc1951).
 #![warn(missing_docs)]
-#![cfg_attr(no_std, feature = "no_std")]
+#![cfg_attr(not(feature = "std"), no_std)]
 
-#[cfg(feature = "no_std")]
 extern crate alloc;
 
 pub use self::default::{DefaultLz77Encoder, DefaultLz77EncoderBuilder};
-#[cfg(feature = "no_std")]
 use alloc::vec::Vec;
-#[cfg(feature = "no_std")]
+use core::cmp;
 use core2::io;
 use rle_decode_fast::rle_decode;
-#[cfg(not(feature = "no_std"))]
-use std::io;
 
 mod default;
 
@@ -180,13 +176,13 @@ impl Lz77Decoder {
                 if self.buffer.len() < backward_distance as usize {
                     return Err(io::Error::new(
                         io::ErrorKind::InvalidData,
-                        #[cfg(not(feature = "no_std"))]
+                        #[cfg(feature = "std")]
                         format!(
                             "Too long backword reference: buffer.len={}, distance={}",
                             self.buffer.len(),
                             backward_distance
                         ),
-                        #[cfg(feature = "no_std")]
+                        #[cfg(not(feature = "std"))]
                         "Too long backword reference",
                     ));
                 }
@@ -240,7 +236,7 @@ impl Lz77Decoder {
 
 impl io::Read for Lz77Decoder {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        let copy_size = std::cmp::min(buf.len(), self.buffer.len() - self.offset);
+        let copy_size = cmp::min(buf.len(), self.buffer.len() - self.offset);
         buf[..copy_size].copy_from_slice(&self.buffer[self.offset..][..copy_size]);
         self.offset += copy_size;
         self.truncate_old_buffer();
@@ -251,12 +247,8 @@ impl io::Read for Lz77Decoder {
 #[cfg(test)]
 mod tests {
     use super::*;
-    #[cfg(feature = "no_std")]
     use alloc::vec::Vec;
-    #[cfg(feature = "no_std")]
     use core2::io::Read as _;
-    #[cfg(not(feature = "no_std"))]
-    use std::io::Read as _;
 
     #[test]
     fn encoder_and_decoder_works() {

src/bit.rs

@@ -1,7 +1,4 @@
-#[cfg(feature = "no_std")]
 use core2::io;
-#[cfg(not(feature = "no_std"))]
-use std::io;
 
 #[derive(Debug)]
 pub struct BitWriter<W> {
@@ -179,10 +176,8 @@ pub(crate) struct BitReaderState {
 #[cfg(test)]
 mod tests {
     use super::*;
-    #[cfg(feature = "no_std")]
+    use alloc::vec::Vec;
     use core2::io;
-    #[cfg(not(feature = "no_std"))]
-    use std::io;
 
     #[test]
     fn writer_works() {

src/checksum.rs

@@ -1,8 +1,5 @@
 use adler32::RollingAdler32;
-#[cfg(feature = "no_std")]
 use core::fmt;
-#[cfg(not(feature = "no_std"))]
-use std::fmt;
 
 pub struct Adler32(RollingAdler32);
 impl Adler32 {

src/deflate/decode.rs

@@ -1,10 +1,7 @@
 use super::symbol;
 use crate::bit;
 use crate::lz77;
-#[cfg(feature = "no_std")]
 use core2::io::{self, Read};
-#[cfg(not(feature = "no_std"))]
-use std::io::{self, Read};
 
 /// DEFLATE decoder.
 #[derive(Debug)]
@@ -23,10 +20,9 @@ where
     ///
     /// # Examples
     /// ```
-    /// #[cfg(feature = "no_std")]
+    /// # extern crate alloc;
+    /// # use alloc::vec::Vec;
     /// use core2::io::{Cursor, Read};
-    /// #[cfg(not(feature = "no_std"))]
-    /// use std::io::{Cursor, Read};
     /// use libflate::deflate::Decoder;
     ///
     /// let encoded_data = [243, 72, 205, 201, 201, 87, 8, 207, 47, 202, 73, 81, 4, 0];
@@ -58,10 +54,7 @@ where
     ///
     /// # Examples
     /// ```
-    /// #[cfg(feature = "no_std")]
     /// use core2::io::Cursor;
-    /// #[cfg(not(feature = "no_std"))]
-    /// use std::io::Cursor;
     /// use libflate::deflate::Decoder;
     ///
     /// let encoded_data = [243, 72, 205, 201, 201, 87, 8, 207, 47, 202, 73, 81, 4, 0];
@@ -105,9 +98,9 @@ where
                     if used != len.into() {
                         Err(io::Error::new(
                             io::ErrorKind::UnexpectedEof,
-                            #[cfg(not(feature = "no_std"))]
+                            #[cfg(feature = "std")]
                             format!("The reader has incorrect length: expected {len}, read {used}"),
-                            #[cfg(feature = "no_std")]
+                            #[cfg(not(feature = "std"))]
                             "The reader has incorrect length",
                         ))
                     } else {
@@ -173,10 +166,10 @@ where
 
 #[cfg(test)]
 mod tests {
-    #[cfg(not(feature = "no_std"))]
+    #[cfg(feature = "std")]
     use super::*;
     use crate::deflate::symbol::{DynamicHuffmanCodec, HuffmanCodec};
-    #[cfg(not(feature = "no_std"))]
+    #[cfg(feature = "std")]
     use std::io;
 
     #[test]
@@ -197,7 +190,7 @@ mod tests {
     }
 
     #[test]
-    #[cfg(not(feature = "no_std"))]
+    #[cfg(feature = "std")]
     fn it_works() {
         let input = [
             180, 253, 73, 143, 28, 201, 150, 46, 8, 254, 150, 184, 139, 75, 18, 69, 247, 32, 157,
@@ -219,7 +212,7 @@ mod tests {
     }
 
     #[test]
-    #[cfg(not(feature = "no_std"))]
+    #[cfg(feature = "std")]
     fn test_issue_64() {
         let input = b"\x04\x04\x04\x05:\x1az*\xfc\x06\x01\x90\x01\x06\x01";
         let mut decoder = Decoder::new(&input[..]);