Expose cargo and rustc version envvars

Author: Jon Gjengset

crates/cargo-test-support/src/lib.rs

@@ -1041,6 +1041,14 @@ pub fn is_nightly() -> bool {
         && (vv.contains("-nightly") || vv.contains("-dev"))
 }
 
+pub fn rustc_release() -> &'static str {
+    RUSTC_INFO
+        .verbose_version
+        .lines()
+        .find_map(|line| line.strip_prefix("release: "))
+        .expect("verbose version has release: field")
+}
+
 pub fn process<T: AsRef<OsStr>>(t: T) -> ProcessBuilder {
     _process(t.as_ref())
 }

src/cargo/core/compiler/custom_build.rs

@@ -254,6 +254,22 @@ fn build_work(cx: &mut Context<'_, '_>, unit: &Unit) -> CargoResult<Job> {
         cmd.env("RUSTC_WRAPPER", wrapper);
     }
     cmd.env("RUSTFLAGS", bcx.rustflags_args(unit).join(" "));
+    let version = crate::version();
+    cmd.env(
+        "CARGO_VERSION",
+        format!("{}.{}.{}", version.major, version.minor, version.patch),
+    );
+    cmd.env("CARGO_VERSION_MAJOR", version.major.to_string());
+    cmd.env("CARGO_VERSION_MINOR", version.minor.to_string());
+    cmd.env("CARGO_VERSION_PATCH", version.patch.to_string());
+    let version = &bcx.rustc().version;
+    cmd.env(
+        "RUSTC_VERSION",
+        format!("{}.{}.{}", version.major, version.minor, version.patch),
+    );
+    cmd.env("RUSTC_VERSION_MAJOR", version.major.to_string());
+    cmd.env("RUSTC_VERSION_MINOR", version.minor.to_string());
+    cmd.env("RUSTC_VERSION_PATCH", version.patch.to_string());
 
     // Gather the set of native dependencies that this package has along with
     // some other variables to close over.

tests/testsuite/build_script.rs

@@ -5,7 +5,9 @@ use cargo_test_support::paths::CargoPathExt;
 use cargo_test_support::registry::Package;
 use cargo_test_support::tools;
 use cargo_test_support::{basic_manifest, cross_compile, is_coarse_mtime, project};
-use cargo_test_support::{rustc_host, sleep_ms, slow_cpu_multiplier, symlink_supported};
+use cargo_test_support::{
+    rustc_host, rustc_release, sleep_ms, slow_cpu_multiplier, symlink_supported,
+};
 use cargo_util::paths::remove_dir_all;
 use std::env;
 use std::fs;
@@ -80,10 +82,11 @@ fn custom_build_env_vars() {
         )
         .file("bar/src/lib.rs", "pub fn hello() {}");
 
+    let cargo_version = cargo::version();
+    let rustc_version = semver::Version::parse(rustc_release()).unwrap();
     let file_content = format!(
         r#"
             use std::env;
-            use std::io::prelude::*;
             use std::path::Path;
 
             fn main() {{
@@ -122,13 +125,37 @@ fn custom_build_env_vars() {
 
                 let rustflags = env::var("RUSTFLAGS").unwrap();
                 assert_eq!(rustflags, "");
+
+                let version = env::var("CARGO_VERSION").unwrap();
+                assert_eq!(version, "{1}.{2}.{3}", "bad cargo version");
+                let version = env::var("CARGO_VERSION_MAJOR").unwrap();
+                assert_eq!(version, "{1}");
+                let version = env::var("CARGO_VERSION_MINOR").unwrap();
+                assert_eq!(version, "{2}");
+                let version = env::var("CARGO_VERSION_PATCH").unwrap();
+                assert_eq!(version, "{3}");
+
+                let version = env::var("RUSTC_VERSION").unwrap();
+                assert_eq!(version, "{4}.{5}.{6}", "bad rust version");
+                let version = env::var("RUSTC_VERSION_MAJOR").unwrap();
+                assert_eq!(version, "{4}");
+                let version = env::var("RUSTC_VERSION_MINOR").unwrap();
+                assert_eq!(version, "{5}");
+                let version = env::var("RUSTC_VERSION_PATCH").unwrap();
+                assert_eq!(version, "{6}");
             }}
         "#,
         p.root()
             .join("target")
             .join("debug")
             .join("build")
-            .display()
+            .display(),
+        cargo_version.major,
+        cargo_version.minor,
+        cargo_version.patch,
+        rustc_version.major,
+        rustc_version.minor,
+        rustc_version.patch,
     );
 
     let p = p.file("bar/build.rs", &file_content).build();