test: requires attribute accepts string literals for cmds (#14875)

### What does this PR try to resolve?

The new syntax is key-value pair like `requires = "rustfmt"`,
comparing to the previous `requires_<cmd>`.

This enables `cargo_test` to require that the CLI contains
non-alphabetic names, such as `llvm-profdata`.

### How should we test and review this PR?

CI passes

### Additional information

This is a request from
<#14859 (comment)>,
but I found it a bit tricky so split off this change first.

Cargo.toml

@@ -32,7 +32,7 @@ cargo-credential-libsecret = { version = "0.4.7", path = "credential/cargo-crede
 cargo-credential-macos-keychain = { version = "0.4.7", path = "credential/cargo-credential-macos-keychain" }
 cargo-credential-wincred = { version = "0.4.7", path = "credential/cargo-credential-wincred" }
 cargo-platform = { path = "crates/cargo-platform", version = "0.2.0" }
-cargo-test-macro = { version = "0.3.0", path = "crates/cargo-test-macro" }
+cargo-test-macro = { version = "0.4.0", path = "crates/cargo-test-macro" }
 cargo-test-support = { version = "0.6.0", path = "crates/cargo-test-support" }
 cargo-util = { version = "0.2.14", path = "crates/cargo-util" }
 cargo-util-schemas = { version = "0.7.0", path = "crates/cargo-util-schemas" }

crates/cargo-test-macro/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "cargo-test-macro"
-version = "0.3.4"
+version = "0.4.0"
 edition.workspace = true
 rust-version = "1.83"  # MSRV:1
 license.workspace = true

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

@@ -34,8 +34,8 @@ use std::sync::Once;
 ///   This is useful for tests that use unstable options in `rustc` or `rustdoc`.
 ///   These tests are run in Cargo's CI, but are disabled in rust-lang/rust's CI due to the difficulty of updating both repos simultaneously.
 ///   A `reason` field is required to explain why it is nightly-only.
-/// * `requires_<cmd>` --- This indicates a command that is required to be installed to be run.
-///   For example, `requires_rustfmt` means the test will only run if the executable `rustfmt` is installed.
+/// * `requires = "<cmd>"` --- This indicates a command that is required to be installed to be run.
+///   For example, `requires = "rustfmt"` means the test will only run if the executable `rustfmt` is installed.
 ///   These tests are *always* run on CI.
 ///   This is mainly used to avoid requiring contributors from having every dependency installed.
 /// * `build_std_real` --- This is a "real" `-Zbuild-std` test (in the `build_std` integration test).
@@ -133,8 +133,18 @@ pub fn cargo_test(attr: TokenStream, item: TokenStream) -> TokenStream {
                     "rustup or stable toolchain not installed"
                 );
             }
-            s if s.starts_with("requires_") => {
+            s if s.starts_with("requires=") => {
                 let command = &s[9..];
+                let Ok(literal) = command.parse::<Literal>() else {
+                    panic!("expect a string literal, found: {command}");
+                };
+                let literal = literal.to_string();
+                let Some(command) = literal
+                    .strip_prefix('"')
+                    .and_then(|lit| lit.strip_suffix('"'))
+                else {
+                    panic!("expect a quoted string literal, found: {literal}");
+                };
                 set_ignore!(!has_command(command), "{command} not installed");
             }
             s if s.starts_with(">=1.") => {

tests/testsuite/cargo_init/simple_hg/mod.rs

@@ -5,7 +5,7 @@ use cargo_test_support::prelude::*;
 use cargo_test_support::str;
 use cargo_test_support::Project;
 
-#[cargo_test(requires_hg)]
+#[cargo_test(requires = "hg")]
 fn case() {
     let project = Project::from_template(current_dir!().join("in"));
     let project_root = &project.root();

tests/testsuite/git.rs

@@ -2917,7 +2917,7 @@ fn failed_submodule_checkout() {
     t.join().unwrap();
 }
 
-#[cargo_test(requires_git)]
+#[cargo_test(requires = "git")]
 fn use_the_cli() {
     let project = project();
     let git_project = git::new("dep1", |project| {
@@ -3028,7 +3028,7 @@ fn templatedir_doesnt_cause_problems() {
     p.cargo("check").run();
 }
 
-#[cargo_test(requires_git)]
+#[cargo_test(requires = "git")]
 fn git_with_cli_force() {
     // Supports a force-pushed repo.
     let git_project = git::new("dep1", |project| {
@@ -3095,7 +3095,7 @@ two
         .run();
 }
 
-#[cargo_test(requires_git)]
+#[cargo_test(requires = "git")]
 fn git_fetch_cli_env_clean() {
     // This tests that git-fetch-with-cli works when GIT_DIR environment
     // variable is set (for whatever reason).
@@ -4069,7 +4069,7 @@ src/lib.rs
         .run();
 }
 
-#[cargo_test(public_network_test, requires_git)]
+#[cargo_test(public_network_test, requires = "git")]
 fn github_fastpath_error_message() {
     let p = project()
         .file(

tests/testsuite/git_gc.rs

@@ -90,7 +90,7 @@ fn run_test(path_env: Option<&OsStr>) {
     );
 }
 
-#[cargo_test(requires_git)]
+#[cargo_test(requires = "git")]
 fn use_git_gc() {
     run_test(None);
 }

tests/testsuite/new.rs

@@ -114,7 +114,7 @@ fn simple_git() {
     cargo_process("build").cwd(&paths::root().join("foo")).run();
 }
 
-#[cargo_test(requires_hg)]
+#[cargo_test(requires = "hg")]
 fn simple_hg() {
     cargo_process("new --lib foo --edition 2015 --vcs hg").run();
 

tests/testsuite/profile_trim_paths.rs

@@ -445,17 +445,17 @@ mod object_works {
             .stdout
     }
 
-    #[cargo_test(requires_nm, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(requires = "nm", nightly, reason = "-Zremap-path-scope is unstable")]
     fn with_split_debuginfo_off() {
         object_works_helper("off", inspect_debuginfo);
     }
 
-    #[cargo_test(requires_nm, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(requires = "nm", nightly, reason = "-Zremap-path-scope is unstable")]
     fn with_split_debuginfo_packed() {
         object_works_helper("packed", inspect_debuginfo);
     }
 
-    #[cargo_test(requires_nm, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(requires = "nm", nightly, reason = "-Zremap-path-scope is unstable")]
     fn with_split_debuginfo_unpacked() {
         object_works_helper("unpacked", inspect_debuginfo);
     }
@@ -475,17 +475,29 @@ mod object_works {
             .stdout
     }
 
-    #[cargo_test(requires_readelf, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(
+        requires = "readelf",
+        nightly,
+        reason = "-Zremap-path-scope is unstable"
+    )]
     fn with_split_debuginfo_off() {
         object_works_helper("off", inspect_debuginfo);
     }
 
-    #[cargo_test(requires_readelf, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(
+        requires = "readelf",
+        nightly,
+        reason = "-Zremap-path-scope is unstable"
+    )]
     fn with_split_debuginfo_packed() {
         object_works_helper("packed", inspect_debuginfo);
     }
 
-    #[cargo_test(requires_readelf, nightly, reason = "-Zremap-path-scope is unstable")]
+    #[cargo_test(
+        requires = "readelf",
+        nightly,
+        reason = "-Zremap-path-scope is unstable"
+    )]
     fn with_split_debuginfo_unpacked() {
         object_works_helper("unpacked", inspect_debuginfo);
     }
@@ -676,7 +688,7 @@ fn custom_build_env_var_trim_paths() {
 }
 
 #[cfg(unix)]
-#[cargo_test(requires_lldb, nightly, reason = "-Zremap-path-scope is unstable")]
+#[cargo_test(requires = "lldb", nightly, reason = "-Zremap-path-scope is unstable")]
 fn lldb_works_after_trimmed() {
     use cargo_test_support::compare::assert_e2e;
     use cargo_util::is_ci;