Clippy fixes (#729)

* plot: clippy: Fix `needless_borrow` lints.

* ci: Enable clippy for all targets in the workspace.

* Update clippy section in `CONTRIBUTING.md`.

* Remove instances of `allow(clippy:all)`.

These are no longer needed.

.github/workflows/ci.yaml

@@ -64,7 +64,7 @@ jobs:
 
       - name: Check for clippy hints
         if: ${{ matrix.rust == 'stable' }}
-        run: cargo clippy -- -D warnings
+        run: cargo clippy --workspace --all-targets -- -D warnings
 
       # This fails on 1.64, but works on 1.66 and later.
       # https://github.com/rust-lang/rust/issues/103306

CONTRIBUTING.md

@@ -33,11 +33,11 @@ cargo test --all
 cargo bench
 ```
 
-It's a good idea to run clippy and fix any warnings as well:
+It's a good idea to run `clippy` and fix any warnings as well:
 
 ```
-rustup component add clippy-preview
-cargo clippy --all
+rustup component add clippy
+cargo clippy --workspace --all-targets
 ```
 
 Finally, run Rustfmt to maintain a common code style:

plot/src/axis.rs

@@ -155,9 +155,6 @@ where
 }
 
 impl<'a> Script for (Axis, &'a Properties) {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let &(axis, properties) = self;
         let axis_ = axis.display();

plot/src/candlestick.rs

@@ -27,9 +27,6 @@ impl Default for Properties {
 }
 
 impl Script for Properties {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let mut script = String::from("with candlesticks ");
 

plot/src/curve.rs

@@ -38,9 +38,6 @@ impl CurveDefault<Style> for Properties {
 }
 
 impl Script for Properties {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let mut script = if let Some(axes) = self.axes {
             format!("axes {} ", axes.display())

plot/src/errorbar.rs

@@ -36,9 +36,6 @@ impl ErrorBarDefault<Style> for Properties {
 }
 
 impl Script for Properties {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let mut script = format!("with {} ", self.style.display());
 

plot/src/filledcurve.rs

@@ -27,9 +27,6 @@ impl Default for Properties {
 }
 
 impl Script for Properties {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let mut script = if let Some(axes) = self.axes {
             format!("axes {} ", axes.display())

plot/src/key.rs

@@ -48,9 +48,6 @@ impl Properties {
 }
 
 impl Script for Properties {
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> String {
         let mut script = if self.hidden {
             return String::from("set key off\n");

plot/src/lib.rs

@@ -438,9 +438,6 @@ impl Figure {
         }
     }
 
-    // Allow clippy::format_push_string even with older versions of rust (<1.62) which
-    // don't have it defined.
-    #[allow(clippy::all)]
     fn script(&self) -> Vec<u8> {
         let mut s = String::new();
 
@@ -1062,7 +1059,7 @@ mod test {
     #[test]
     fn test_parse_version_on_valid_string() {
         let string = "gnuplot 5.0 patchlevel 7";
-        let version = super::parse_version(&string).unwrap();
+        let version = super::parse_version(string).unwrap();
         assert_eq!(5, version.major);
         assert_eq!(0, version.minor);
         assert_eq!("7", &version.patch);
@@ -1071,7 +1068,7 @@ mod test {
     #[test]
     fn test_parse_gentoo_version() {
         let string = "gnuplot 5.2 patchlevel 5a (Gentoo revision r0)";
-        let version = super::parse_version(&string).unwrap();
+        let version = super::parse_version(string).unwrap();
         assert_eq!(5, version.major);
         assert_eq!(2, version.minor);
         assert_eq!("5a", &version.patch);