Formatting without fmt::Debug (#76)

* More efficient string formatting

* Fixed escaping

* Format without fmt::Debug dependency

* Test fmt-debug=none

.github/workflows/check.yml

@@ -47,9 +47,11 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
     runs-on: ${{ matrix.os }}
+    env:
+      RUSTFLAGS: -Zfmt-debug=none
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@stable
+      - uses: dtolnay/rust-toolchain@nightly
         with:
           targets: x86_64-unknown-none
       - run: cargo test --no-default-features

src/dependencies.rs

@@ -1,3 +1,4 @@
+use crate::util::TupleArrayDisplay;
 use crate::{write_str_variable, write_variable};
 use std::{collections, fs, io, path};
 
@@ -85,8 +86,8 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     write_variable!(
         w,
         "DEPENDENCIES",
-        format!("[(&str, &str); {}]", dependencies.deps.len()),
-        format!("{0:?}", dependencies.deps),
+        format_args!("[(&str, &str); {}]", dependencies.deps.len()),
+        TupleArrayDisplay(&dependencies.deps),
         "An array of effective dependencies as documented by `Cargo.lock`."
     );
     write_str_variable!(
@@ -104,8 +105,8 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     write_variable!(
         w,
         "DIRECT_DEPENDENCIES",
-        format!("[(&str, &str); {}]", dependencies.direct_deps.len()),
-        format!("{0:?}", dependencies.direct_deps),
+        format_args!("[(&str, &str); {}]", dependencies.direct_deps.len()),
+        TupleArrayDisplay(&dependencies.direct_deps),
         "An array of direct dependencies as documented by `Cargo.lock`."
     );
     write_str_variable!(
@@ -123,8 +124,8 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     write_variable!(
         w,
         "INDIRECT_DEPENDENCIES",
-        format!("[(&str, &str); {}]", dependencies.indirect_deps.len()),
-        format!("{0:?}", dependencies.indirect_deps),
+        format_args!("[(&str, &str); {}]", dependencies.indirect_deps.len()),
+        TupleArrayDisplay(&dependencies.indirect_deps),
         "An array of indirect dependencies as documented by `Cargo.lock`."
     );
     write_str_variable!(
@@ -155,8 +156,8 @@ pub fn write_dependencies(manifest_location: &path::Path, mut w: &fs::File) -> i
     write_variable!(
         w,
         "DEPENDENCIES",
-        format!("[(&str, &str); {}]", deps.len()),
-        format!("{deps:?}"),
+        format_args!("[(&str, &str); {}]", deps.len()),
+        TupleArrayDisplay(&deps),
         "An array of effective dependencies as documented by `Cargo.lock`."
     );
     write_str_variable!(

src/environment.rs

@@ -1,3 +1,4 @@
+use crate::util::ArrayDisplay;
 use crate::{fmt_option_str, write_str_variable, write_variable};
 use std::{collections, env, ffi, fmt, fs, io, process};
 
@@ -141,8 +142,8 @@ impl EnvironmentMap {
         write_variable!(
             w,
             "FEATURES",
-            format!("[&str; {}]", features.len()),
-            format!("{features:?}"),
+            format_args!("[&str; {}]", features.len()),
+            ArrayDisplay(&features, |t, f| write!(f, "\"{}\"", t.escape_default())),
             "The features that were enabled during compilation."
         );
         let features_str = features.join(", ");
@@ -162,8 +163,12 @@ impl EnvironmentMap {
         write_variable!(
             w,
             "FEATURES_LOWERCASE",
-            format!("[&str; {}]", lowercase_features.len()),
-            format!("{lowercase_features:?}"),
+            format_args!("[&str; {}]", lowercase_features.len()),
+            ArrayDisplay(&lowercase_features, |val, fmt| write!(
+                fmt,
+                "\"{}\"",
+                val.escape_default()
+            )),
             "The features as above, as lowercase strings."
         );
         let lowercase_features_str = lowercase_features.join(", ");
@@ -237,13 +242,21 @@ impl EnvironmentMap {
         let rustc_version = get_version_from_cmd(rustc.as_ref())?;
         let rustdoc_version = get_version_from_cmd(rustdoc.as_ref()).unwrap_or_default();
 
-        let doc = format!("The output of `{rustc} -V`");
-        write_str_variable!(w, "RUSTC_VERSION", rustc_version, doc);
+        write_str_variable!(
+            w,
+            "RUSTC_VERSION",
+            rustc_version,
+            format_args!("The output of `{rustc} -V`")
+        );
 
-        let doc = format!(
-            "The output of `{rustdoc} -V`; empty string if `{rustdoc} -V` failed to execute"
+        write_str_variable!(
+            w,
+            "RUSTDOC_VERSION",
+            rustdoc_version,
+            format_args!(
+                "The output of `{rustdoc} -V`; empty string if `{rustdoc} -V` failed to execute"
+            )
         );
-        write_str_variable!(w, "RUSTDOC_VERSION", rustdoc_version, doc);
         Ok(())
     }
 

src/git.rs

@@ -202,7 +202,7 @@ mod tests {
 
         let commit_oid_short = binding.as_str().unwrap();
 
-        let commit_hash = format!("{commit_oid}");
+        let commit_hash = commit_oid.to_string();
         let commit_hash_short = commit_oid_short.to_string();
 
         assert!(commit_hash.starts_with(&commit_hash_short));
@@ -285,7 +285,7 @@ mod tests {
 
         let commit_oid_short = binding.as_str().unwrap();
 
-        let commit_hash = format!("{commit_oid}");
+        let commit_hash = commit_oid.to_string();
         let commit_hash_short = commit_oid_short.to_string();
 
         assert!(commit_hash.starts_with(&commit_hash_short));

src/lib.rs

@@ -336,7 +336,7 @@ macro_rules! write_str_variable {
             $writer,
             $name,
             "&str",
-            format!("r\"{}\"", $value.escape_default()),
+            format_args!("\"{}\"", $value.escape_default()),
             $doc
         );
     };

src/util.rs

@@ -1,5 +1,8 @@
 //! Various convenience functions for `built` at runtime.
 
+use std::fmt;
+use std::fmt::Write;
+
 #[cfg(feature = "git2")]
 pub use crate::git::{get_repo_description, get_repo_head};
 
@@ -55,3 +58,45 @@ where
 pub fn detect_ci() -> Option<super::CIPlatform> {
     crate::environment::EnvironmentMap::new().detect_ci()
 }
+
+pub(crate) struct ArrayDisplay<'a, T, F>(pub &'a [T], pub F)
+where
+    F: Fn(&T, &mut fmt::Formatter<'_>) -> fmt::Result;
+
+impl<T, F> fmt::Display for ArrayDisplay<'_, T, F>
+where
+    F: Fn(&T, &mut fmt::Formatter<'_>) -> fmt::Result,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.write_char('[')?;
+        for (i, v) in self.0.iter().enumerate() {
+            if i != 0 {
+                f.write_str(", ")?;
+            }
+            (self.1)(v, f)?;
+        }
+        f.write_char(']')
+    }
+}
+
+#[cfg(feature = "cargo-lock")]
+pub(crate) struct TupleArrayDisplay<'a, T>(pub &'a [(T, T)]);
+
+#[cfg(feature = "cargo-lock")]
+impl<T> fmt::Display for TupleArrayDisplay<'_, T>
+where
+    T: AsRef<str>,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(
+            f,
+            "{}",
+            ArrayDisplay(self.0, |(a, b), fmt| write!(
+                fmt,
+                r#"("{}", "{}")"#,
+                a.as_ref().escape_default(),
+                b.as_ref().escape_default()
+            ))
+        )
+    }
+}

tests/testbox_tests.rs

@@ -46,8 +46,9 @@ version = "0.0.1"
 build = "build.rs"
 
 [build-dependencies]
-built = {{ path = {:?}, features = {} }}"#,
-                &built_root, &features,
+built = {{ path = "{}", features = {} }}"#,
+                built_root.display().to_string().escape_default(),
+                &features,
             ),
         )
         .add_file(
@@ -167,7 +168,7 @@ repository = "https://dev.example.com/sources/testbox/"
 license = "MIT"
 
 [build-dependencies]
-built = {{ path = {:?}, default_features=false }}
+built = {{ path = "{}", default_features=false }}
 
 [profile.dev]
 panic = "abort"
@@ -179,7 +180,7 @@ panic = "abort"
 default = ["SuperAwesome", "MegaAwesome"]
 SuperAwesome = []
 MegaAwesome = []"#,
-            &built_root,
+            built_root.display().to_string().escape_default(),
         ),
     )
     .add_file(
@@ -237,16 +238,16 @@ repository = "https://dev.example.com/sources/testbox/"
 license = "MIT"
 
 [dependencies]
-built = {{ path = {:?}, default_features=false }}
+built = {{ path = "{built_root}", default_features=false }}
 
 [build-dependencies]
-built = {{ path = {:?}, default_features=false }}
+built = {{ path = "{built_root}", default_features=false }}
 
 [features]
 default = ["SuperAwesome", "MegaAwesome"]
 SuperAwesome = []
 MegaAwesome = []"#,
-            &built_root, &built_root
+            built_root = built_root.display().to_string().escape_default()
         ),
     );
 
@@ -327,8 +328,8 @@ version = "5.6.7"
 build = "build.rs"
 
 [build-dependencies]
-built = {{ path = {:?} }}"#,
-            &built_root
+built = {{ path = "{}" }}"#,
+            built_root.display().to_string().escape_default()
         ),
     );
     p.add_file(
@@ -371,16 +372,16 @@ repository = "https://dev.example.com/sources/testbox/"
 license = "MIT"
 
 [dependencies]
-built = {{ path = {:?}, features=["cargo-lock", "dependency-tree", "git2", "chrono", "semver"] }}
+built = {{ path = "{built_root}", features=["cargo-lock", "dependency-tree", "git2", "chrono", "semver"] }}
 
 [build-dependencies]
-built = {{ path = {:?}, features=["cargo-lock", "dependency-tree", "git2", "chrono", "semver"] }}
+built = {{ path = "{built_root}", features=["cargo-lock", "dependency-tree", "git2", "chrono", "semver"] }}
 
 [features]
 default = ["SuperAwesome", "MegaAwesome"]
 SuperAwesome = []
 MegaAwesome = []"#,
-            &built_root, &built_root
+            built_root = built_root.display().to_string().escape_default()
         ),
     );
 
@@ -485,11 +486,11 @@ build = "build.rs"
 description = "xobtset"
 
 [dependencies]
-built = {{ path = {:?}, features=["chrono"] }}
+built = {{ path = "{built_root}", features=["chrono"] }}
 
 [build-dependencies]
-built = {{ path = {:?}, features=["chrono"] }}"#,
-            &built_root, &built_root
+built = {{ path = "{built_root}", features=["chrono"] }}"#,
+            built_root = built_root.display().to_string().escape_default()
         ),
     );