Crate built

Provides a crate with information from the time it was built.

built is used as a build-time dependency to collect various information about the build-environment, serialize this information into Rust-code and provide that to the crate. The information collected by built include:

• Various metadata like version, authors, homepage etc. as set by Cargo.toml
• The tag or commit id if the crate was being compiled from within a Git repository.
• The values of CARGO_CFG_* build script environment variables, like CARGO_CFG_TARGET_OS and CARGO_CFG_TARGET_ARCH.
• The features the crate was compiled with.
• The various dependencies, dependencies of dependencies and their versions Cargo ultimately chose to compile.
• The presence of a CI-platform like Github Actions, Travis CI and AppVeyor.
• The compiler and it’s version; the documentation-generator and it’s version.

built does not add any further runtime-dependencies to a crate; all information is serialized as types from stdlib. One can include built as a runtime-dependency and use it’s convenience functions.

To add built to a crate, add it as a build-time dependency, use a build-script to collect and serialize the build-time information, and include! the generated code.

Add this to Cargo.toml:

[package]
build = "build.rs"

[build-dependencies]
built = "0.7"

Add or modify a build-script. In build.rs:

fn main() {
    built::write_built_file().expect("Failed to acquire build-time information");
}

The build-script will by default write a file named built.rs into Cargo’s output directory. It can be picked up in main.rs (or anywhere else) like this:

// Use of a mod or pub mod is not actually necessary.
pub mod built_info {
   // The file has been placed there by the build script.
   include!(concat!(env!("OUT_DIR"), "/built.rs"));
}

…and then used somewhere in the crate’s code:

/// Determine if current version is a pre-release or was built from a git-repo
fn release_is_unstable() -> bool {
    return !built_info::PKG_VERSION_PRE.is_empty() || built_info::GIT_VERSION.is_some()
}

/// Default log-level, enhanced on CI
fn default_log_level() -> LogLevel {
    if built_info::CI_PLATFORM.is_some() {
        LogLevel::TRACE
    } else {
        LogLevel::ERROR
    }
}

/// The time this crate was built
#[cfg(feature = "chrono")]
fn built_time() -> built::chrono::DateTime<built::chrono::Local> {
    built::util::strptime(built_info::BUILT_TIME_UTC)
        .with_timezone(&built::chrono::offset::Local)
}

/// If another crate pulls in a dependency we don't like, print a warning
#[cfg(feature = "semver")]
fn check_sane_dependencies() {
    if built::util::parse_versions(&built_info::DEPENDENCIES)
                    .any(|(name, ver)| name == "DeleteAllMyFiles"
                                       && ver < built::semver::Version::parse("1.1.4").unwrap()) {
        eprintln!("DeleteAllMyFiles < 1.1.4 may not delete all your files. Beware!");
    }
}

---

Feature flags

The information that built collects and makes available in built.rs depends on the features that were enabled on the build-time dependency.

Always available

The following information is available regardless of feature-flags.

/// The Continuous Integration platform detected during compilation.
pub const CI_PLATFORM: Option<&str> = None;

/// The full version.
pub const PKG_VERSION: &str = "0.1.0";
/// The major version.
pub const PKG_VERSION_MAJOR: &str = "0";
/// The minor version.
pub const PKG_VERSION_MINOR: &str = "1";
/// "The patch version.
pub const PKG_VERSION_PATCH: &str = "0";
/// "The pre-release version.
pub const PKG_VERSION_PRE: &str = "";

/// "A colon-separated list of authors.
pub const PKG_AUTHORS: &str = "Lukas Lueg <lukas.lueg@gmail.com>";

/// The name of the package.
pub const PKG_NAME: &str = "example_project";
/// "The description.
pub const PKG_DESCRIPTION: &str = "";
/// "The homepage.
pub const PKG_HOMEPAGE: &str = "";
/// "The license.
pub const PKG_LICENSE: &str = "MIT";
/// The source repository as advertised in Cargo.toml.
pub const PKG_REPOSITORY: &str = "";

/// The target triple that was being compiled for.
pub const TARGET: &str = "x86_64-unknown-linux-gnu";
/// The host triple of the rust compiler.
pub const HOST: &str = "x86_64-unknown-linux-gnu";
/// `release` for release builds, `debug` for other builds.
pub const PROFILE: &str = "debug";

/// The compiler that cargo resolved to use.
pub const RUSTC: &str = "rustc";
/// The documentation-generator that cargo resolved to use.
pub const RUSTDOC: &str = "rustdoc";
/// The output of `rustc -V`
pub const RUSTC_VERSION: &str = "rustc 1.43.1 (8d69840ab 2020-05-04)";
/// The output of `rustdoc -V`
pub const RUSTDOC_VERSION: &str = "rustdoc 1.43.1 (8d69840ab 2020-05-04)";

/// Value of OPT_LEVEL for the profile used during compilation.
pub const OPT_LEVEL: &str = "0";
/// The parallelism that was specified during compilation.
pub const NUM_JOBS: u32 = 8;
/// "Value of DEBUG for the profile used during compilation.
pub const DEBUG: bool = true;

/// The features that were enabled during compilation.
pub const FEATURES: [&str; 0] = [];
/// The features as a comma-separated string.
pub const FEATURES_STR: &str = "";
/// The features as above, as lowercase strings.
pub const FEATURES_LOWERCASE: [&str; 0] = [];
/// The feature-string as above, from lowercase strings.
pub const FEATURES_LOWERCASE_STR: &str = "";

/// The target architecture, given by `CARGO_CFG_TARGET_ARCH`.
pub const CFG_TARGET_ARCH: &str = "x86_64";
/// The endianness, given by `CARGO_CFG_TARGET_ENDIAN`.
pub const CFG_ENDIAN: &str = "little";
/// The toolchain-environment, given by `CARGO_CFG_TARGET_ENV`.
pub const CFG_ENV: &str = "gnu";
/// The OS-family, given by `CARGO_CFG_TARGET_FAMILY`.
pub const CFG_FAMILY: &str = "unix";
/// The operating system, given by `CARGO_CFG_TARGET_OS`.
pub const CFG_OS: &str = "linux";
/// The pointer width, given by `CARGO_CFG_TARGET_POINTER_WIDTH`.
pub const CFG_POINTER_WIDTH: &str = "64";

cargo-lock

Parses Cargo.lockand generates representations of dependencies and their versions.

For this to work, Cargo.lock needs to actually be there; this is (usually) only true for executables and not for libraries. Cargo will only create a Cargo.lock for the top-level crate in a dependency-tree. In case of a library, the top-level crate will decide which crate/version combination to compile and there will be no Cargo.lock while the library gets compiled as a dependency.

Parsing Cargo.lock instead of Cargo.toml allows to serialize the precise versions Cargo chose to compile. One can’t, however, distinguish build-dependencies, dev-dependencies and dependencies. Furthermore, some dependencies never show up if Cargo had not been forced to actually use them (e.g. dev-dependencies with cargo test never having been executed).

Note that if the dependency-tree-feature is not active, the list of dependencies contains the root-package(s) as well.

/// An array of effective dependencies as documented by `Cargo.lock`.
pub const DEPENDENCIES: [(&str, &str); 37] = [("autocfg", "1.0.0"), ("bitflags", "1.2.1"), ("built", "0.4.1"), ("cargo-lock", "4.0.1"), ("cc", "1.0.54"), ("cfg-if", "0.1.10"), ("chrono", "0.4.11"), ("example_project", "0.1.0"), ("git2", "0.13.6"), ("idna", "0.2.0"), ("jobserver", "0.1.21"), ("libc", "0.2.71"), ("libgit2-sys", "0.12.6+1.0.0"), ("libz-sys", "1.0.25"), ("log", "0.4.8"), ("matches", "0.1.8"), ("num-integer", "0.1.42"), ("num-traits", "0.2.11"), ("percent-encoding", "2.1.0"), ("pkg-config", "0.3.17"), ("proc-macro2", "1.0.17"), ("quote", "1.0.6"), ("semver", "1.0.0"), ("serde", "1.0.110"), ("serde_derive", "1.0.110"), ("smallvec", "1.4.0"), ("syn", "1.0.25"), ("time", "0.1.43"), ("toml", "0.5.6"), ("unicode-bidi", "0.3.4"), ("unicode-normalization", "0.1.12"), ("unicode-xid", "0.2.0"), ("url", "2.1.1"), ("vcpkg", "0.2.8"), ("winapi", "0.3.8"), ("winapi-i686-pc-windows-gnu", "0.4.0"), ("winapi-x86_64-pc-windows-gnu", "0.4.0")];
/// The effective dependencies as a comma-separated string.
pub const DEPENDENCIES_STR: &str = "autocfg 1.0.0, bitflags 1.2.1, built 0.4.1, cargo-lock 4.0.1, cc 1.0.54, cfg-if 0.1.10, chrono 0.4.11, example_project 0.1.0, git2 0.13.6, idna 0.2.0, jobserver 0.1.21, libc 0.2.71, libgit2-sys 0.12.6+1.0.0, libz-sys 1.0.25, log 0.4.8, matches 0.1.8, num-integer 0.1.42, num-traits 0.2.11, percent-encoding 2.1.0, pkg-config 0.3.17, proc-macro2 1.0.17, quote 1.0.6, semver 1.0.0, serde 1.0.110, serde_derive 1.0.110, smallvec 1.4.0, syn 1.0.25, time 0.1.43, toml 0.5.6, unicode-bidi 0.3.4, unicode-normalization 0.1.12, unicode-xid 0.2.0, url 2.1.1, vcpkg 0.2.8, winapi 0.3.8, winapi-i686-pc-windows-gnu 0.4.0, winapi-x86_64-pc-windows-gnu 0.4.0";

dependency-tree (implies cargo-lock)

Solve the dependency-graph in Cargo.lock to discern direct and indirect dependencies.

“Direct” dependencies are those which the root-package(s) depends on. “Indirect” dependencies are those which are not direct dependencies.

/// An array of direct dependencies as documented by `Cargo.lock`.
pub const DIRECT_DEPENDENCIES: [(&str, &str); 1] = [("built", "0.6.1")];
/// The direct dependencies as a comma-separated string.
pub const DIRECT_DEPENDENCIES_STR: &str = r"built 0.6.1";

/// An array of indirect dependencies as documented by `Cargo.lock`.
pub const INDIRECT_DEPENDENCIES: [(&str, &str); 64] = [("android-tzdata", "0.1.1"), ("android_system_properties", "0.1.5"), ("autocfg", "1.1.0"), ("bitflags", "2.4.0"), ("bumpalo", "3.13.0"), ("cargo-lock", "9.0.0"), ("cc", "1.0.83"), ("cfg-if", "1.0.0"), ("chrono", "0.4.29"), ("core-foundation-sys", "0.8.4"), ("equivalent", "1.0.1"), ("example_project", "0.1.0"), ("fixedbitset", "0.4.2"), ("form_urlencoded", "1.2.0"), ("git2", "0.18.0"), ("hashbrown", "0.14.0"), ("iana-time-zone", "0.1.57"), ("iana-time-zone-haiku", "0.1.2"), ("idna", "0.4.0"), ("indexmap", "2.0.0"), ("jobserver", "0.1.26"), ("js-sys", "0.3.64"), ("libc", "0.2.147"), ("libgit2-sys", "0.16.1+1.7.1"), ("libz-sys", "1.1.12"), ("log", "0.4.20"), ("memchr", "2.6.3"), ("num-traits", "0.2.16"), ("once_cell", "1.18.0"), ("percent-encoding", "2.3.0"), ("petgraph", "0.6.4"), ("pkg-config", "0.3.27"), ("proc-macro2", "1.0.66"), ("quote", "1.0.33"), ("semver", "1.0.18"), ("serde", "1.0.188"), ("serde_derive", "1.0.188"), ("serde_spanned", "0.6.3"), ("syn", "2.0.31"), ("tinyvec", "1.6.0"), ("tinyvec_macros", "0.1.1"), ("toml", "0.7.6"), ("toml_datetime", "0.6.3"), ("toml_edit", "0.19.14"), ("unicode-bidi", "0.3.13"), ("unicode-ident", "1.0.11"), ("unicode-normalization", "0.1.22"), ("url", "2.4.1"), ("vcpkg", "0.2.15"), ("wasm-bindgen", "0.2.87"), ("wasm-bindgen-backend", "0.2.87"), ("wasm-bindgen-macro", "0.2.87"), ("wasm-bindgen-macro-support", "0.2.87"), ("wasm-bindgen-shared", "0.2.87"), ("windows", "0.48.0"), ("windows-targets", "0.48.5"), ("windows_aarch64_gnullvm", "0.48.5"), ("windows_aarch64_msvc", "0.48.5"), ("windows_i686_gnu", "0.48.5"), ("windows_i686_msvc", "0.48.5"), ("windows_x86_64_gnu", "0.48.5"), ("windows_x86_64_gnullvm", "0.48.5"), ("windows_x86_64_msvc", "0.48.5"), ("winnow", "0.5.15")];
/// The indirect dependencies as a comma-separated string.
pub const INDIRECT_DEPENDENCIES_STR: &str = r"android-tzdata 0.1.1, android_system_properties 0.1.5, autocfg 1.1.0, bitflags 2.4.0, bumpalo 3.13.0, cargo-lock 9.0.0, cc 1.0.83, cfg-if 1.0.0, chrono 0.4.29, core-foundation-sys 0.8.4, equivalent 1.0.1, example_project 0.1.0, fixedbitset 0.4.2, form_urlencoded 1.2.0, git2 0.18.0, hashbrown 0.14.0, iana-time-zone 0.1.57, iana-time-zone-haiku 0.1.2, idna 0.4.0, indexmap 2.0.0, jobserver 0.1.26, js-sys 0.3.64, libc 0.2.147, libgit2-sys 0.16.1+1.7.1, libz-sys 1.1.12, log 0.4.20, memchr 2.6.3, num-traits 0.2.16, once_cell 1.18.0, percent-encoding 2.3.0, petgraph 0.6.4, pkg-config 0.3.27, proc-macro2 1.0.66, quote 1.0.33, semver 1.0.18, serde 1.0.188, serde_derive 1.0.188, serde_spanned 0.6.3, syn 2.0.31, tinyvec 1.6.0, tinyvec_macros 0.1.1, toml 0.7.6, toml_datetime 0.6.3, toml_edit 0.19.14, unicode-bidi 0.3.13, unicode-ident 1.0.11, unicode-normalization 0.1.22, url 2.4.1, vcpkg 0.2.15, wasm-bindgen 0.2.87, wasm-bindgen-backend 0.2.87, wasm-bindgen-macro 0.2.87, wasm-bindgen-macro-support 0.2.87, wasm-bindgen-shared 0.2.87, windows 0.48.0, windows-targets 0.48.5, windows_aarch64_gnullvm 0.48.5, windows_aarch64_msvc 0.48.5, windows_i686_gnu 0.48.5, windows_i686_msvc 0.48.5, windows_x86_64_gnu 0.48.5, windows_x86_64_gnullvm 0.48.5, windows_x86_64_msvc 0.48.5, winnow 0.5.15";

git2

Try to open the git-repository at manifest_location and retrieve HEAD tag or commit id.

Notice that GIT_HEAD_REF is None if HEAD is detached or not valid UTF-8.

Continuous Integration platforms like Travis and AppVeyor will do shallow clones, causing libgit2 to be unable to get a meaningful result. GIT_VERSION and GIT_DIRTY will therefor always be None if a CI-platform is detected.

/// If the crate was compiled from within a git-repository,
/// `GIT_VERSION` contains HEAD's tag. The short commit id is used
/// if HEAD is not tagged.
pub const GIT_VERSION: Option<&str> = Some("0.4.1-10-gca2af4f");

/// If the repository had dirty/staged files.
pub const GIT_DIRTY: Option<bool> = Some(true);

/// If the crate was compiled from within a git-repository,
/// `GIT_HEAD_REF` contains full name to the reference pointed to by
/// HEAD (e.g.: `refs/heads/master`). If HEAD is detached or the branch
/// name is not valid UTF-8 `None` will be stored.
pub const GIT_HEAD_REF: Option<&str> = Some("refs/heads/master");

/// If the crate was compiled from within a git-repository,
/// `GIT_COMMIT_HASH` contains HEAD's full commit SHA-1 hash.
pub const GIT_COMMIT_HASH: Option<&str> = Some("ca2af4f11bb8f4f6421c4cccf428bf4862573daf");

/// If the crate was compiled from within a git-repository,
/// `GIT_COMMIT_HASH_SHORT` contains HEAD's short commit SHA-1 hash.
pub const GIT_COMMIT_HASH_SHORT: Option<&str> = Some("ca2af4f");

chrono

The build-time is recorded as BUILT_TIME_UTC. If built is included as a runtime-dependency, it can parse the string-representation into a time:Tm with the help of built::util::strptime().

/// The built-time in RFC2822, UTC
pub const BUILT_TIME_UTC: &str = "Wed, 27 May 2020 18:12:39 +0000";

Re-exports

• pub use semver;
• pub use chrono;

Modules

• util
  Various convenience functions for built at runtime.

Enums

• CIPlatform
  Various Continuous Integration platforms whose presence can be detected.

Functions

• write_built_file
  A shorthand for calling write_built_file() with CARGO_MANIFEST_DIR and [OUT_DIR]/built.rs.
• write_built_file_with_opts
  Writes rust-code describing the crate at manifest_location to a new file named dst.