Bump vergen from 3.2.0 to 4.0.2

[dependabot-preview]

Bumps vergen from 3.2.0 to 4.0.2.

Release notes

Sourced from vergen's releases.

v4.0.1

• Documentation updates

v4.0.0

Release 4.0 Breaking Changes

• The main entry point for use has changed from generate_cargo_keys to gen
• There are now 3 features that allow you to control what instructions can be generated (build, git, and rustc).
  • The build feature enables the VERGEN_BUILD_* instructions.
  • The git feature enables the VERGEN_GIT_* instructions, the cargo:rerun-if-changed instructions, and the REBUILD_ON_HEAD_CHANGE flag.
  • The rustc feature enables the VERGEN_RUSTC_* instructions.
  • By default, all three features are enabled.
  • You can build with all three features disabled, which basically make the gen function a no-op.
  • You can still use ConstantsFlags to toggle individual cargo instructions.
• The generated instructions have been normalized. Therefore, you may need to update what env variable you are referring to in code. I've included a list below of the full set of instructions that can be generated for reference.

cargo:rustc-env=VERGEN_BUILD_DATE=2021-02-12
cargo:rustc-env=VERGEN_BUILD_TIMESTAMP=2021-02-12T01:54:15.134750+00:00
cargo:rustc-env=VERGEN_GIT_BRANCH=feature/git2
cargo:rustc-env=VERGEN_GIT_COMMIT_DATE=2021-02-11T20:05:53-05:00
cargo:rustc-env=VERGEN_GIT_SEMVER=v3.2.0-86-g95fc0f5
cargo:rustc-env=VERGEN_GIT_SEMVER_LIGHTWEIGHT=blah-33-g95fc0f5
cargo:rustc-env=VERGEN_GIT_SHA=95fc0f5d066710f16e0c23ce3239d6e040abca0d
cargo:rustc-env=VERGEN_GIT_SHA_SHORT=95fc0f5
cargo:rustc-env=VERGEN_RUSTC_CHANNEL=nightly
cargo:rustc-env=VERGEN_RUSTC_COMMIT_DATE=2021-02-10
cargo:rustc-env=VERGEN_RUSTC_COMMIT_HASH=07194ffcd25b0871ce560b9f702e52db27ac9f77
cargo:rustc-env=VERGEN_RUSTC_HOST_TRIPLE=x86_64-apple-darwin
cargo:rustc-env=VERGEN_RUSTC_LLVM_VERSION=11.0
cargo:rustc-env=VERGEN_RUSTC_SEMVER=1.52.0-nightly
cargo:rerun-if-changed=/Users/yoda/projects/rust-lang/vergen/.git/HEAD
cargo:rerun-if-changed=/Users/yoda/projects/rust-lang/vergen/.git/refs/heads/feature/git2

• Under the hood, the Commands used for git have been removed in lieu of using the git2 library directly.
• git2 is also used to determine the HEAD path and the path that it refers to for the cargo:rerun-if-changed instructions. This is more reliable then the manual method that was in place before.
• I've migrated the CI stuff from Travis to GitHub Actions.

Commits

• See full diff in compare view

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[tomtau]

#2520

[dependabot-preview]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.