[Clippy] Add clippy to CI, allow current violations at a module level

.github/workflows/main.yml

@@ -47,6 +47,34 @@ jobs:
     - run: cargo run -p systest
     - run: cargo run -p systest --features unstable-sha256
 
+  clippy:
+    name: Clippy
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        build: [stable, beta, windows]
+        include:
+          - build: stable
+            os: ubuntu-latest
+            rust: stable
+          - build: beta
+            os: ubuntu-latest
+            rust: beta
+          - build: windows
+            os: windows-2022
+            rust: stable
+    steps:
+    - uses: actions/checkout@master
+      with:
+        submodules: true
+    - name: Install Rust (rustup)
+      run: rustup update ${{ matrix.rust }} --no-self-update && rustup default ${{ matrix.rust }}
+      shell: bash
+    - name: Install Clippy (rustup)
+      run: rustup component add clippy
+    - run: cargo clippy --all-targets --all-features -- -Dwarnings
+
   rustfmt:
     name: Rustfmt
     runs-on: ubuntu-latest

examples/add.rs

@@ -14,6 +14,7 @@
 
 #![deny(warnings)]
 #![allow(trivial_casts)]
+#![allow(clippy::needless_borrows_for_generic_args)]
 
 use clap::Parser;
 use git2::Repository;

examples/clone.rs

@@ -13,6 +13,8 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::explicit_auto_deref)]
+#![allow(clippy::manual_checked_ops)]
 
 use clap::Parser;
 use git2::build::{CheckoutBuilder, RepoBuilder};

examples/diff.rs

@@ -13,6 +13,9 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::explicit_auto_deref)]
+#![allow(clippy::needless_borrows_for_generic_args)]
+#![allow(clippy::redundant_closure)]
 
 use clap::Parser;
 use git2::{Blob, Diff, DiffOptions, Error, Object, ObjectType, Oid, Repository};

examples/init.rs

@@ -13,6 +13,7 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::manual_strip)]
 
 use clap::Parser;
 use git2::ObjectFormat;

examples/log.rs

@@ -13,6 +13,8 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::manual_strip)]
+#![allow(clippy::needless_borrowed_reference)]
 
 use clap::Parser;
 use git2::{Commit, DiffOptions, ObjectType, Repository, Signature, Time};

examples/pull.rs

@@ -12,6 +12,9 @@
  * <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
+#![allow(clippy::needless_borrow)]
+#![allow(clippy::needless_question_mark)]
+
 use clap::Parser;
 use git2::Repository;
 use std::io::{self, Write};

examples/rev-list.rs

@@ -14,6 +14,7 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::manual_strip)]
 
 use clap::Parser;
 use git2::{Error, Oid, Repository, Revwalk};

examples/tag.rs

@@ -13,6 +13,7 @@
  */
 
 #![deny(warnings)]
+#![allow(clippy::explicit_auto_deref)]
 
 use clap::Parser;
 use git2::{Commit, Error, Repository, Tag};

libgit2-sys/build.rs

@@ -1,3 +1,6 @@
+#![allow(clippy::needless_borrows_for_generic_args)]
+#![allow(clippy::unnecessary_map_or)]
+
 use std::env;
 use std::fs;
 use std::io;

libgit2-sys/lib.rs

@@ -1,5 +1,6 @@
 #![doc(html_root_url = "https://docs.rs/libgit2-sys/0.18")]
 #![allow(non_camel_case_types, unused_extern_crates)]
+#![allow(clippy::legacy_numeric_constants)]
 
 // This is required to link libz when libssh2-sys is not included.
 extern crate libz_sys as libz;

src/apply.rs

@@ -1,6 +1,9 @@
 //! git_apply support
 //! see original: <https://github.com/libgit2/libgit2/blob/master/include/git2/apply.h>
 
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::new_without_default)]
+
 use crate::{panic, raw, util::Binding, DiffDelta, DiffHunk};
 use libc::c_int;
 use std::{ffi::c_void, mem};
@@ -149,6 +152,7 @@ impl<'cb> ApplyOptions<'cb> {
 }
 
 #[cfg(test)]
+#[allow(clippy::needless_borrows_for_generic_args)]
 mod tests {
     use super::*;
     use std::{fs::File, io::Write, path::Path};

src/blame.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::redundant_closure)]
+
 use crate::util::{self, Binding};
 use crate::{raw, signature, Error, Oid, Repository, Signature};
 use libc::c_char;
@@ -388,6 +390,9 @@ impl<'blame> FusedIterator for BlameIter<'blame> {}
 impl<'blame> ExactSizeIterator for BlameIter<'blame> {}
 
 #[cfg(test)]
+#[allow(clippy::bool_assert_comparison)]
+#[allow(clippy::needless_borrow)]
+#[allow(clippy::needless_borrows_for_generic_args)]
 mod tests {
     use std::fs::{self, File};
     use std::path::Path;

src/blob.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::io_other_error)]
+
 use std::io;
 use std::marker;
 use std::mem;

src/branch.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::missing_safety_doc)]
+
 use std::ffi::CString;
 use std::marker;
 use std::ptr;

src/buf.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::explicit_auto_deref)]
+
 use std::ops::{Deref, DerefMut};
 use std::ptr;
 use std::slice;

src/build.rs

@@ -1,5 +1,8 @@
 //! Builder-pattern objects for configuration various git operations.
 
+#![allow(clippy::manual_non_exhaustive)]
+#![allow(clippy::missing_safety_doc)]
+
 use libc::{c_char, c_int, c_uint, c_void, size_t};
 use std::ffi::{CStr, CString};
 use std::mem;
@@ -767,6 +770,8 @@ impl TreeUpdateBuilder {
 }
 
 #[cfg(test)]
+#[allow(clippy::needless_borrow)]
+#[allow(clippy::needless_borrows_for_generic_args)]
 mod tests {
     use super::{CheckoutBuilder, RepoBuilder, TreeUpdateBuilder};
     use crate::{CheckoutNotificationType, FileMode, Repository};

src/call.rs

@@ -1,3 +1,4 @@
+#![allow(clippy::needless_lifetimes)]
 #![macro_use]
 
 use crate::Error;

src/cherrypick.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::new_without_default)]
+
 use std::mem;
 
 use crate::build::CheckoutBuilder;

src/commit.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::redundant_closure)]
+
 use std::iter::FusedIterator;
 use std::marker;
 use std::mem;
@@ -413,6 +415,8 @@ impl<'repo> Drop for Commit<'repo> {
 }
 
 #[cfg(test)]
+#[allow(clippy::bool_assert_comparison)]
+#[allow(clippy::let_and_return)]
 mod tests {
     #[test]
     fn smoke() {

src/config.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::should_implement_trait)]
+
 use std::ffi::CString;
 use std::marker;
 use std::path::{Path, PathBuf};
@@ -639,6 +641,7 @@ impl<'cfg> Drop for ConfigEntry<'cfg> {
 }
 
 #[cfg(test)]
+#[allow(clippy::bool_assert_comparison)]
 mod tests {
     use std::fs::File;
     use tempfile::TempDir;

src/cred.rs

@@ -1,3 +1,10 @@
+#![allow(clippy::manual_strip)]
+#![allow(clippy::match_result_ok)]
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::needless_borrowed_reference)]
+#![allow(clippy::needless_borrows_for_generic_args)]
+#![allow(clippy::should_implement_trait)]
+
 #[cfg(feature = "cred")]
 use log::{debug, trace};
 use std::ffi::CString;
@@ -495,6 +502,8 @@ impl CredentialHelper {
 
 #[cfg(test)]
 #[cfg(feature = "cred")]
+#[allow(clippy::unused_io_amount)]
+#[allow(clippy::useless_conversion)]
 mod test {
     use std::env;
     use std::fs::File;

src/diff.rs

@@ -1,3 +1,7 @@
+#![allow(clippy::empty_docs)]
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::new_without_default)]
+
 use libc::{c_char, c_int, c_void, size_t};
 use std::ffi::CString;
 use std::iter::FusedIterator;
@@ -1588,6 +1592,9 @@ impl DiffPatchidOptions {
 }
 
 #[cfg(test)]
+#[allow(clippy::assign_op_pattern)]
+#[allow(clippy::needless_borrows_for_generic_args)]
+#[allow(clippy::while_let_on_iterator)]
 mod tests {
     #[cfg(feature = "unstable-sha256")]
     use crate::Diff;

src/email.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::too_many_arguments)]
+
 use std::ffi::CString;
 use std::{mem, ptr};
 

src/error.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::should_implement_trait)]
+
 use libc::c_int;
 use std::env::JoinPathsError;
 use std::error;

src/index.rs

@@ -882,6 +882,8 @@ impl Binding for IndexEntry {
 }
 
 #[cfg(test)]
+#[allow(clippy::needless_borrow)]
+#[allow(clippy::needless_borrows_for_generic_args)]
 mod tests {
     use std::fs::{self, File};
     use std::path::Path;

src/indexer.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::io_other_error)]
+
 use std::ffi::CStr;
 use std::path::Path;
 use std::{io, marker, mem, ptr};
@@ -242,6 +244,7 @@ impl Drop for Indexer<'_> {
 }
 
 #[cfg(test)]
+#[allow(clippy::unused_io_amount)]
 mod tests {
     use crate::{Buf, Indexer};
     use std::io::prelude::*;

src/lib.rs

@@ -70,6 +70,9 @@
 #![deny(missing_docs)]
 #![warn(rust_2018_idioms)]
 #![cfg_attr(test, deny(warnings))]
+#![allow(clippy::needless_lifetimes)]
+#![allow(clippy::should_implement_trait)]
+#![allow(clippy::unnecessary_cast)]
 
 use bitflags::bitflags;
 use libgit2_sys as raw;

src/mailmap.rs

@@ -93,6 +93,7 @@ impl Mailmap {
 }
 
 #[cfg(test)]
+#[allow(clippy::needless_borrow)]
 mod tests {
     use super::*;
 

src/merge.rs

@@ -1,3 +1,6 @@
+#![allow(clippy::missing_safety_doc)]
+#![allow(clippy::redundant_closure)]
+
 use libc::{c_char, c_uint, c_ushort, size_t};
 use std::ffi::CString;
 use std::marker;

src/message.rs

@@ -1,3 +1,7 @@
+#![allow(clippy::len_without_is_empty)]
+#![allow(clippy::needless_borrow)]
+#![allow(clippy::redundant_closure)]
+
 use core::ops::Range;
 use std::ffi::CStr;
 use std::ffi::CString;
@@ -237,6 +241,7 @@ fn to_bytes_tuple(trailers: &MessageTrailers, index: usize) -> (&[u8], &[u8]) {
 }
 
 #[cfg(test)]
+#[allow(clippy::char_lit_as_u8)]
 mod tests {
 
     #[test]

src/odb.rs

@@ -1,3 +1,8 @@
+#![allow(clippy::io_other_error)]
+#![allow(clippy::len_without_is_empty)]
+#![allow(clippy::single_match)]
+#![allow(clippy::should_implement_trait)]
+
 use std::io;
 use std::marker;
 use std::ptr;
@@ -579,6 +584,8 @@ pub(crate) extern "C" fn write_pack_progress_cb(
 }
 
 #[cfg(test)]
+#[allow(clippy::bool_assert_comparison)]
+#[allow(clippy::unused_io_amount)]
 mod tests {
     use crate::{Buf, ObjectType, Oid, Repository};
     use std::io::prelude::*;

src/oid_array.rs

@@ -1,5 +1,7 @@
 //! Bindings to libgit2's raw `git_oidarray` type
 
+#![allow(clippy::extra_unused_lifetimes)]
+
 use std::ops::Deref;
 
 use crate::oid::Oid;

src/opts.rs

@@ -1,5 +1,7 @@
 //! Bindings to libgit2's git_libgit2_opts function.
 
+#![allow(clippy::missing_safety_doc)]
+
 use std::ffi::CString;
 use std::ptr;
 

src/packbuilder.rs

@@ -1,3 +1,5 @@
+#![allow(clippy::redundant_closure)]
+
 use libc::{c_int, c_uint, c_void, size_t};
 use std::marker;
 use std::path::Path;
@@ -296,6 +298,7 @@ extern "C" fn progress_c(
 }
 
 #[cfg(test)]
+#[allow(clippy::bool_assert_comparison)]
 mod tests {
     use crate::Buf;
 

src/pathspec.rs

@@ -337,6 +337,7 @@ impl<'list> FusedIterator for PathspecFailedEntries<'list> {}
 impl<'list> ExactSizeIterator for PathspecFailedEntries<'list> {}
 
 #[cfg(test)]
+#[allow(clippy::needless_borrows_for_generic_args)]
 mod tests {
     use super::Pathspec;
     use crate::PathspecFlags;