chore: use variables in Rust format strings

Change this:

    format!("{}", foo)

into this:

    format!("{foo}")

Support for this feature was added in Rust 1.58 (see
https://github.com/rust-lang/rust/releases/tag/1.58.0) and in 1.67
clippy suggests about this. Because the new style seems to be where
the Rust ecosystem is going, I think Subplot should follow to avoid
being needlessly different from most other projects.

Sponsored-by: author

1 files changed, 4 insertions, 8 deletions

diff --git a/build.rs b/build.rs
index 857452b..2276f93 100644
--- a/build.rs
+++ b/build.rs
@@ -127,15 +127,11 @@ fn write_out_resource_file<'a>(paths: impl Iterator<Item = &'a Path>) -> Result<
 /// to contain `BUILTIN_{var}` to either the env value, or `{def}` if not
 /// provided.
 fn adopt_env_var(var: &str, def: &str) {
-    println!("cargo:rerun-if-env-changed=SUBPLOT_{var}", var = var);
-    if let Ok(value) = std::env::var(format!("SUBPLOT_{var}", var = var)) {
-        println!(
-            "cargo:rustc-env=BUILTIN_{var}={value}",
-            var = var,
-            value = value
-        );
+    println!("cargo:rerun-if-env-changed=SUBPLOT_{var}");
+    if let Ok(value) = std::env::var(format!("SUBPLOT_{var}")) {
+        println!("cargo:rustc-env=BUILTIN_{var}={value}",);
     } else {
-        println!("cargo:rustc-env=BUILTIN_{var}={def}", var = var, def = def);
+        println!("cargo:rustc-env=BUILTIN_{var}={def}");
     }
 }