Auto merge of #9732 - djc:rust-version-docs, r=ehuss

Stabilize the rust-version field

I've tried to make the documentation here fairly comprehensive. I've also updated the first version for the 2021 edition, which should now be stable pending substantial unforeseen changes.

See #8072.

CHANGELOG.md

@@ -5,6 +5,8 @@
 
 ### Added
 
+- Added support for the [`rust-version`](https://doc.rust-lang.org/nightly/cargo/reference/manifest.html#the-rust-version-field)
+  field in a crate's metadata and the `--ignore-rust-version` command line option.
 - Build scripts can now pass additional linker arguments for binaries or all
   linkable targets. [docs](https://doc.rust-lang.org/nightly/cargo/reference/build-scripts.html#outputs-of-the-build-script)
   [#9557](https://github.com/rust-lang/cargo/pull/9557)

src/cargo/core/features.rs

@@ -166,8 +166,7 @@ impl Edition {
         match self {
             Edition2015 => None,
             Edition2018 => Some(semver::Version::new(1, 31, 0)),
-            // FIXME: This will likely be 1.56, update when that seems more likely.
-            Edition2021 => Some(semver::Version::new(1, 62, 0)),
+            Edition2021 => Some(semver::Version::new(1, 56, 0)),
         }
     }
 
@@ -396,7 +395,7 @@ features! {
     (unstable, strip, "", "reference/unstable.html#profile-strip-option"),
 
     // Specifying a minimal 'rust-version' attribute for crates
-    (unstable, rust_version, "", "reference/unstable.html#rust-version"),
+    (stable, rust_version, "1.56", "reference/manifest.html#the-rust-version-field"),
 
     // Support for 2021 edition.
     (unstable, edition2021, "", "reference/unstable.html#edition-2021"),

src/cargo/util/command_prelude.rs

@@ -218,7 +218,7 @@ pub trait AppExt: Sized {
     fn arg_ignore_rust_version(self) -> Self {
         self._arg(opt(
             "ignore-rust-version",
-            "Ignore `rust-version` specification in packages (unstable)",
+            "Ignore `rust-version` specification in packages",
         ))
     }
 
@@ -533,12 +533,6 @@ pub trait ArgMatchesExt {
             honor_rust_version: !self._is_present("ignore-rust-version"),
         };
 
-        if !opts.honor_rust_version {
-            config
-                .cli_unstable()
-                .fail_if_stable_opt("--ignore-rust-version", 8072)?;
-        }
-
         if let Some(ws) = workspace {
             self.check_optional_opts(ws, &opts)?;
         } else if self.is_present_with_zero_values("package") {

src/cargo/util/toml/mod.rs

@@ -1122,46 +1122,25 @@ impl TomlManifest {
         }
 
         let rust_version = if let Some(rust_version) = &project.rust_version {
-            if features.require(Feature::rust_version()).is_err() {
-                let mut msg =
-                    "`rust-version` is not supported on this version of Cargo and will be ignored"
-                        .to_string();
-                if config.nightly_features_allowed {
-                    msg.push_str(
-                        "\n\n\
-                        consider adding `cargo-features = [\"rust-version\"]` to the manifest",
-                    );
-                } else {
-                    msg.push_str(
-                        "\n\n\
-                        this Cargo does not support nightly features, but if you\n\
-                        switch to nightly channel you can add\n\
-                        `cargo-features = [\"rust-version\"]` to enable this feature",
-                    );
+            let req = match semver::VersionReq::parse(rust_version) {
+                // Exclude semver operators like `^` and pre-release identifiers
+                Ok(req) if rust_version.chars().all(|c| c.is_ascii_digit() || c == '.') => req,
+                _ => bail!("`rust-version` must be a value like \"1.32\""),
+            };
+            if let Some(first_version) = edition.first_version() {
+                let unsupported =
+                    semver::Version::new(first_version.major, first_version.minor - 1, 9999);
+                if req.matches(&unsupported) {
+                    bail!(
+                        "rust-version {} is older than first version ({}) required by \
+                            the specified edition ({})",
+                        rust_version,
+                        first_version,
+                        edition,
+                    )
                 }
-                warnings.push(msg);
-                None
-            } else {
-                let req = match semver::VersionReq::parse(rust_version) {
-                    // Exclude semver operators like `^` and pre-release identifiers
-                    Ok(req) if rust_version.chars().all(|c| c.is_ascii_digit() || c == '.') => req,
-                    _ => bail!("`rust-version` must be a value like \"1.32\""),
-                };
-                if let Some(first_version) = edition.first_version() {
-                    let unsupported =
-                        semver::Version::new(first_version.major, first_version.minor - 1, 9999);
-                    if req.matches(&unsupported) {
-                        bail!(
-                            "rust-version {} is older than first version ({}) required by \
-                                the specified edition ({})",
-                            rust_version,
-                            first_version,
-                            edition,
-                        )
-                    }
-                }
-                Some(rust_version.clone())
             }
+            Some(rust_version.clone())
         } else {
             None
         };

src/doc/man/cargo-bench.md

@@ -83,6 +83,8 @@ target.
 
 {{> options-target-triple }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-build.md

@@ -35,6 +35,8 @@ they have `required-features` that are missing.
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-check.md

@@ -42,6 +42,8 @@ they have `required-features` that are missing.
 
 {{> options-profile }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-doc.md

@@ -64,6 +64,8 @@ flag and will always document the given target.
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-fix.md

@@ -122,6 +122,8 @@ When no target selection options are given, `cargo fix` will fix all targets
 
 {{> options-profile }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-run.md

@@ -50,6 +50,8 @@ Run the specified example.
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-rustc.md

@@ -47,6 +47,8 @@ binary and library targets of the selected package.
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-rustdoc.md

@@ -62,6 +62,8 @@ if its name is the same as the lib target. Binaries are skipped if they have
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/cargo-test.md

@@ -102,6 +102,8 @@ target options.
 
 {{> options-release }}
 
+{{> options-ignore-rust-version }}
+
 {{/options}}
 
 ### Output Options

src/doc/man/generated_txt/cargo-bench.txt

@@ -202,6 +202,11 @@ OPTIONS
            <https://doc.rust-lang.org/cargo/guide/build-cache.html>
            documentation for more details.
 
+       --ignore-rust-version
+           Benchmark the target even if the selected Rust compiler is older
+           than the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-build.txt

@@ -146,6 +146,11 @@ OPTIONS
            Build optimized artifacts with the release profile. See the PROFILES
            section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Build the target even if the selected Rust compiler is older than
+           the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-check.txt

@@ -158,6 +158,11 @@ OPTIONS
            have it check unit tests which are usually excluded via the cfg
            attribute. This does not change the actual profile used.
 
+       --ignore-rust-version
+           Check the target even if the selected Rust compiler is older than
+           the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-doc.txt

@@ -123,6 +123,11 @@ OPTIONS
            Document optimized artifacts with the release profile. See the
            PROFILES section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Document the target even if the selected Rust compiler is older than
+           the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-fix.txt

@@ -231,6 +231,11 @@ OPTIONS
            it fix unit tests which are usually excluded via the cfg attribute.
            This does not change the actual profile used.
 
+       --ignore-rust-version
+           Fix the target even if the selected Rust compiler is older than the
+           required Rust version as configured in the project's rust-version
+           field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-run.txt

@@ -75,6 +75,11 @@ OPTIONS
            Run optimized artifacts with the release profile. See the PROFILES
            section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Run the target even if the selected Rust compiler is older than the
+           required Rust version as configured in the project's rust-version
+           field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-rustc.txt

@@ -137,6 +137,11 @@ OPTIONS
            Build optimized artifacts with the release profile. See the PROFILES
            section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Build the target even if the selected Rust compiler is older than
+           the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-rustdoc.txt

@@ -146,6 +146,11 @@ OPTIONS
            Document optimized artifacts with the release profile. See the
            PROFILES section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Document the target even if the selected Rust compiler is older than
+           the required Rust version as configured in the project's
+           rust-version field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/generated_txt/cargo-test.txt

@@ -223,6 +223,11 @@ OPTIONS
            Test optimized artifacts with the release profile. See the PROFILES
            section for details on how this affects profile selection.
 
+       --ignore-rust-version
+           Test the target even if the selected Rust compiler is older than the
+           required Rust version as configured in the project's rust-version
+           field.
+
    Output Options
        --target-dir directory
            Directory for all generated artifacts and intermediate files. May

src/doc/man/includes/options-ignore-rust-version.md

@@ -0,0 +1,4 @@
+{{#option "`--ignore-rust-version`"}}
+{{actionverb}} the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's `rust-version` field.
+{{/option}}

src/doc/src/commands/cargo-bench.md

@@ -245,6 +245,12 @@ target artifacts are placed in a separate directory. See the
 
 
 
+<dt class="option-term" id="option-cargo-bench---ignore-rust-version"><a class="option-anchor" href="#option-cargo-bench---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Benchmark the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-build.md

@@ -188,6 +188,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-build---ignore-rust-version"><a class="option-anchor" href="#option-cargo-build---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Build the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-check.md

@@ -202,6 +202,12 @@ used.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-check---ignore-rust-version"><a class="option-anchor" href="#option-cargo-check---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Check the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-doc.md

@@ -161,6 +161,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-doc---ignore-rust-version"><a class="option-anchor" href="#option-cargo-doc---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Document the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-fix.md

@@ -282,6 +282,12 @@ used.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-fix---ignore-rust-version"><a class="option-anchor" href="#option-cargo-fix---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Fix the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-run.md

@@ -106,6 +106,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-run---ignore-rust-version"><a class="option-anchor" href="#option-cargo-run---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Run the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-rustc.md

@@ -175,6 +175,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-rustc---ignore-rust-version"><a class="option-anchor" href="#option-cargo-rustc---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Build the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-rustdoc.md

@@ -190,6 +190,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-rustdoc---ignore-rust-version"><a class="option-anchor" href="#option-cargo-rustdoc---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Document the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/commands/cargo-test.md

@@ -269,6 +269,12 @@ selection.</dd>
 
 
 
+<dt class="option-term" id="option-cargo-test---ignore-rust-version"><a class="option-anchor" href="#option-cargo-test---ignore-rust-version"></a><code>--ignore-rust-version</code></dt>
+<dd class="option-desc">Test the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's <code>rust-version</code> field.</dd>
+
+
+
 </dl>
 
 ### Output Options

src/doc/src/reference/manifest.md

@@ -9,6 +9,7 @@ in the [TOML] format. Every manifest file consists of the following sections:
   * [`version`](#the-version-field) — The version of the package.
   * [`authors`](#the-authors-field) — The authors of the package.
   * [`edition`](#the-edition-field) — The Rust edition.
+  * [`rust-version`](#the-rust-version-field) — The minimal supported Rust version.
   * [`description`](#the-description-field) — A description of the package.
   * [`documentation`](#the-documentation-field) — URL of the package documentation.
   * [`readme`](#the-readme-field) — Path to the package's README file.
@@ -144,6 +145,33 @@ assumed for backwards compatibility. Note that all manifests
 created with [`cargo new`] will not use this historical fallback because they
 will have `edition` explicitly specified to a newer value.
 
+#### The `rust-version` field
+
+The `rust-version` field is an optional key that tells cargo what version of the
+Rust language and compiler your package can be compiled with. If the currently
+selected version of the Rust compiler is older than the stated version, cargo
+will exit with an error, telling the user what version is required.
+
+The first version of Cargo that supports this field was released with Rust 1.56.0.
+In older releases, the field will be ignored, and Cargo will display a warning.
+
+```toml
+[package]
+# ...
+rust-version = "1.56"
+```
+
+The Rust version must be a bare version number with two or three components; it
+cannot include semver operators or pre-release identifiers. Compiler pre-release
+identifiers such as -nightly will be ignored while checking the Rust version.
+The `rust-version` must be equal to or newer than the version that first
+introduced the configured `edition`.
+
+The `rust-version` may be ignored using the `--ignore-rust-version` option.
+
+Setting the `rust-version` key in `[package]` will affect all targets/crates in
+the package, including test suites, benchmarks, binaries, examples, etc.
+
 #### The `description` field
 
 The description is a short blurb about the package. [crates.io] will display

src/doc/src/reference/unstable.md

@@ -89,7 +89,6 @@ Each new feature described below should explain how to use it.
     * [Custom named profiles](#custom-named-profiles) — Adds custom named profiles in addition to the standard names.
     * [Profile `strip` option](#profile-strip-option) — Forces the removal of debug information and symbols from executables.
     * [per-package-target](#per-package-target) — Sets the `--target` to use for each individual package.
-    * [rust-version](#rust-version) — Allows to declare the minimum supported Rust version.
     * [Edition 2021](#edition-2021) — Adds support for the 2021 Edition.
 * Information and metadata
     * [Build-plan](#build-plan) — Emits JSON information on which commands will be run.
@@ -1170,25 +1169,6 @@ cargo logout -Z credential-process
 [crates.io]: https://crates.io/
 [config file]: config.md
 
-### rust-version
-* RFC: [#2495](https://github.com/rust-lang/rfcs/blob/master/text/2495-min-rust-version.md)
-* rustc Tracking Issue: [#65262](https://github.com/rust-lang/rust/issues/65262)
-
-The `-Z rust-version` flag enables the reading of the `rust-version` field in the
-Cargo manifest `package` section. This can be used by a package to state a minimal
-version of the compiler required to build the package. An error is generated if
-the version of rustc is older than the stated `rust-version`. The
-`--ignore-rust-version` flag can be used to override the check.
-
-```toml
-cargo-features = ["rust-version"]
-
-[package]
-name = "mypackage"
-version = "0.0.1"
-rust-version = "1.42"
-```
-
 ### edition 2021
 * Tracking Issue: [rust-lang/rust#85811](https://github.com/rust-lang/rust/issues/85811)
 
@@ -1420,3 +1400,9 @@ The `configurable-env` feature to specify environment variables in Cargo
 configuration has been stabilized in the 1.56 release. See the [config
 documentation](config.html#env) for more information about configuring
 environment variables.
+
+### rust-version
+
+The `rust-version` field in `Cargo.toml` has been stabilized in the 1.56 release.
+See the [rust-version field](manifest.html#the-rust-version-field) for more
+information on using the `rust-version` field and the `--ignore-rust-version` option.

src/etc/man/cargo-bench.1

@@ -250,6 +250,12 @@ Note that specifying this flag makes Cargo run in a different mode where the
 target artifacts are placed in a separate directory. See the
 \fIbuild cache\fR <https://doc.rust\-lang.org/cargo/guide/build\-cache.html> documentation for more details.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Benchmark the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-build.1

@@ -175,6 +175,12 @@ Build optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Build the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-check.1

@@ -189,6 +189,12 @@ This is useful to have it check unit tests which are usually
 excluded via the \fBcfg\fR attribute. This does not change the actual profile
 used.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Check the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-doc.1

@@ -142,6 +142,12 @@ Document optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Document the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-fix.1

@@ -284,6 +284,12 @@ This is useful to have it fix unit tests which are usually
 excluded via the \fBcfg\fR attribute. This does not change the actual profile
 used.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Fix the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-run.1

@@ -86,6 +86,12 @@ Run optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Run the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-rustc.1

@@ -161,6 +161,12 @@ Build optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Build the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-rustdoc.1

@@ -172,6 +172,12 @@ Document optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Document the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

src/etc/man/cargo-test.1

@@ -272,6 +272,12 @@ Test optimized artifacts with the \fBrelease\fR profile. See the
 PROFILES section for details on how this affects profile
 selection.
 .RE
+.sp
+\fB\-\-ignore\-rust\-version\fR
+.RS 4
+Test the target even if the selected Rust compiler is older than the
+required Rust version as configured in the project's \fBrust\-version\fR field.
+.RE
 .SS "Output Options"
 .sp
 \fB\-\-target\-dir\fR \fIdirectory\fR

tests/testsuite/rust_version.rs

@@ -2,58 +2,12 @@
 
 use cargo_test_support::{project, registry::Package};
 
-#[cargo_test]
-fn rust_version_gated() {
-    project()
-        .file(
-            "Cargo.toml",
-            r#"
-                [package]
-                name = "foo"
-                version = "0.0.1"
-                rust-version = "1.9999"
-            "#,
-        )
-        .file("src/lib.rs", "")
-        .build()
-        .cargo("build")
-        .masquerade_as_nightly_cargo()
-        .with_stderr_contains(
-            "warning: `rust-version` is not supported on this version of Cargo and will be ignored\
-            \n\nconsider adding `cargo-features = [\"rust-version\"]` to the manifest",
-        )
-        .run();
-
-    project()
-        .file(
-            "Cargo.toml",
-            r#"
-                [package]
-                name = "foo"
-                version = "0.0.1"
-                rust-version = "1.9999"
-            "#,
-        )
-        .file("src/lib.rs", "")
-        .build()
-        .cargo("build")
-        .with_stderr_contains(
-            "warning: `rust-version` is not supported on this version of Cargo and will be ignored\
-            \n\nthis Cargo does not support nightly features, but if you\n\
-            switch to nightly channel you can add\n\
-            `cargo-features = [\"rust-version\"]` to enable this feature",
-        )
-        .run();
-}
-
 #[cargo_test]
 fn rust_version_satisfied() {
     let p = project()
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -66,10 +20,8 @@ fn rust_version_satisfied() {
         .file("src/main.rs", "fn main() {}")
         .build();
 
-    p.cargo("build").masquerade_as_nightly_cargo().run();
-    p.cargo("build --ignore-rust-version -Zunstable-options")
-        .masquerade_as_nightly_cargo()
-        .run();
+    p.cargo("build").run();
+    p.cargo("build --ignore-rust-version").run();
 }
 
 #[cargo_test]
@@ -78,8 +30,6 @@ fn rust_version_bad_caret() {
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -92,7 +42,6 @@ fn rust_version_bad_caret() {
         .file("src/main.rs", "fn main() {}")
         .build()
         .cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr(
             "error: failed to parse manifest at `[..]`\n\n\
@@ -107,8 +56,6 @@ fn rust_version_bad_pre_release() {
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -121,7 +68,6 @@ fn rust_version_bad_pre_release() {
         .file("src/main.rs", "fn main() {}")
         .build()
         .cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr(
             "error: failed to parse manifest at `[..]`\n\n\
@@ -136,8 +82,6 @@ fn rust_version_bad_nonsense() {
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -150,7 +94,6 @@ fn rust_version_bad_nonsense() {
         .file("src/main.rs", "fn main() {}")
         .build()
         .cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr(
             "error: failed to parse manifest at `[..]`\n\n\
@@ -165,8 +108,6 @@ fn rust_version_too_high() {
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -180,22 +121,18 @@ fn rust_version_too_high() {
         .build();
 
     p.cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr(
             "error: package `foo v0.0.1 ([..])` cannot be built because it requires \
              rustc 1.9876.0 or newer, while the currently active rustc version is [..]",
         )
         .run();
-    p.cargo("build --ignore-rust-version -Zunstable-options")
-        .masquerade_as_nightly_cargo()
-        .run();
+    p.cargo("build --ignore-rust-version").run();
 }
 
 #[cargo_test]
 fn rust_version_dependency_fails() {
     Package::new("bar", "0.0.1")
-        .cargo_feature("rust-version")
         .rust_version("1.2345.0")
         .file("src/lib.rs", "fn other_stuff() {}")
         .publish();
@@ -216,7 +153,6 @@ fn rust_version_dependency_fails() {
         .build();
 
     p.cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr(
             "    Updating `[..]` index\n \
@@ -226,9 +162,7 @@ fn rust_version_dependency_fails() {
              rustc 1.2345.0 or newer, while the currently active rustc version is [..]",
         )
         .run();
-    p.cargo("build --ignore-rust-version -Zunstable-options")
-        .masquerade_as_nightly_cargo()
-        .run();
+    p.cargo("build --ignore-rust-version").run();
 }
 
 #[cargo_test]
@@ -237,8 +171,6 @@ fn rust_version_older_than_edition() {
         .file(
             "Cargo.toml",
             r#"
-            cargo-features = ["rust-version"]
-
             [project]
             name = "foo"
             version = "0.0.1"
@@ -252,7 +184,6 @@ fn rust_version_older_than_edition() {
         .file("src/main.rs", "fn main() {}")
         .build()
         .cargo("build")
-        .masquerade_as_nightly_cargo()
         .with_status(101)
         .with_stderr_contains("  rust-version 1.1 is older than first version (1.31.0) required by the specified edition (2018)",
         )