fix: Respect --locked flag

When using `--rust-version`, the lockfile can be blown away.
While that is a problem in of its own,
this focuses on an incremental step of not blowing it away if `--locked`
is used.

This is part of #234

README.md

@@ -54,6 +54,9 @@ OPTIONS:
         --manifest-path <PATH>
             Path to Cargo.toml.
 
+        --locked
+            Require Cargo.lock is up to date.
+
     -F, --features <FEATURES>...
             Space or comma separated list of features to activate.
 

src/cli.rs

@@ -21,6 +21,8 @@ pub(crate) struct Args {
 
     pub(crate) subcommand: Option<String>,
 
+    /// --locked
+    pub(crate) locked: bool,
     /// --manifest-path <PATH>
     pub(crate) manifest_path: Option<String>,
     /// --no-manifest-path
@@ -154,6 +156,7 @@ impl Args {
         let mut clean_per_version = false;
         let mut keep_going = false;
         let mut print_command_list = false;
+        let mut locked = false;
         let mut no_manifest_path = false;
         let mut rust_version = false;
         let mut version_range = None;
@@ -306,6 +309,7 @@ impl Args {
                 Long("clean-per-version") => parse_flag!(clean_per_version),
                 Long("keep-going") => parse_flag!(keep_going),
                 Long("print-command-list") => parse_flag!(print_command_list),
+                Long("locked") => parse_flag!(locked),
                 Long("no-manifest-path") => parse_flag!(no_manifest_path),
                 Long("ignore-unknown-features") => parse_flag!(ignore_unknown_features),
                 Short('v') | Long("verbose") => verbose += 1,
@@ -624,6 +628,7 @@ impl Args {
             clean_per_version,
             keep_going,
             print_command_list,
+            locked,
             no_manifest_path,
             include_features: include_features.into_iter().map(Into::into).collect(),
             at_least_one_of,
@@ -700,6 +705,7 @@ const HELP: &[HelpText<'_>] = &[
         "This flag can only be used together with --workspace",
     ]),
     ("", "--manifest-path", "<PATH>", "Path to Cargo.toml", &[]),
+    ("", "--locked", "", "Require Cargo.lock is up to date", &[]),
     ("-F", "--features", "<FEATURES>...", "Space or comma separated list of features to activate", &[]),
     ("", "--each-feature", "", "Perform for each feature of the package", &[
         "This also includes runs with just --no-default-features flag, and default features.",

src/main.rs

@@ -114,7 +114,7 @@ fn try_main() -> Result<()> {
 
             // First, generate the lockfile using the oldest cargo specified.
             // https://github.com/taiki-e/cargo-hack/issues/105
-            let mut generate_lockfile = true;
+            let mut generate_lockfile = !cx.locked;
             // Workaround for spurious "failed to select a version" error.
             // (This does not work around the underlying cargo bug: https://github.com/rust-lang/cargo/issues/10623)
             let mut regenerate_lockfile_on_51_or_up = false;
@@ -392,6 +392,9 @@ fn exec_on_packages(
     keep_going: &mut KeepGoing,
     cargo_version: u32,
 ) -> Result<()> {
+    if cx.locked {
+        line.arg("--locked");
+    }
     if cx.target.is_empty() || cargo_version >= 64 {
         // TODO: We should test that cargo's multi-target build does not break the resolver behavior required for a correct check.
         for target in &cx.target {
@@ -625,6 +628,9 @@ fn exec_cargo_inner(
 fn cargo_clean(cx: &Context, id: Option<&PackageId>) -> Result<()> {
     let mut line = cx.cargo();
     line.arg("clean");
+    if cx.locked {
+        line.arg("--locked");
+    }
     if let Some(id) = id {
         line.arg("--package");
         line.arg(&cx.packages(id).name);

tests/long-help.txt

@@ -24,6 +24,9 @@ OPTIONS:
         --manifest-path <PATH>
             Path to Cargo.toml.
 
+        --locked
+            Require Cargo.lock is up to date.
+
     -F, --features <FEATURES>...
             Space or comma separated list of features to activate.
 

tests/short-help.txt

@@ -12,6 +12,7 @@ OPTIONS:
         --workspace                      Perform command for all packages in the workspace
         --exclude <SPEC>...              Exclude packages from the check
         --manifest-path <PATH>           Path to Cargo.toml
+        --locked                         Require Cargo.lock is up to date
     -F, --features <FEATURES>...         Space or comma separated list of features to activate
         --each-feature                   Perform for each feature of the package
         --feature-powerset               Perform for the feature powerset of the package