Fail early if required tools can't be found.

[duckinator]

text version of the above screenshot

~/test/sometest main+ dist build

  × The following tools are required to run this task, but are missing:
  │ - cargo-auditable
  │ - cargo-cyclonedx
  │ - omnibor-cli
  help: Please install the tools mentioned above and try again.

~/test/sometest main+ dist build --target x86_64-pc-windows-msvc

  × The following tools are required to run this task, but are missing:
  │ - cargo-auditable
  │ - cargo-cyclonedx
  │ - omnibor-cli
  │ - cargo-xwin
  help: Please install the tools mentioned above and try again.

[mistydemeo]

Looks like this has tripped up the tests - let's take a look and make sure we're not introducing tool dep bounds on things that don't actually need them.

[mistydemeo]

Looking good. It might be nice to handle Cargo itself at some point, for users building non-Rust software, but this all looks great.

[duckinator]

Turns out Cargo is handled separately, and tasks::gather_work() can't succeed unless we either don't need or need and have Cargo, so checking for it in do_env_test doesn't make much sense.

As a note for the future, in case that changes, the approach I found that would theoretically work (if the code ever got run) is adding Tools::cargo_tool() -> DistResult<&Tool> alongside Tools::cargo() -> DistResult<&CargoInfo>, then in do_env_test() you can treat it as a normal tool but use .cargo_tool() instead of .cargo().

diff

diff --git a/cargo-dist/src/lib.rs b/cargo-dist/src/lib.rs
index b02525e7..7c1906ed 100644
--- a/cargo-dist/src/lib.rs
+++ b/cargo-dist/src/lib.rs
@@ -70,6 +70,7 @@ pub fn do_env_test(cfg: &Config) -> DistResult<()> {
     let need_omnibor = builds.omnibor;
     let mut need_xwin = false;
     let mut need_zigbuild = false;
+    let mut need_cargo = false;
 
     let tools = dist.tools;
     let host = tools.host_target.parse()?;
@@ -82,6 +83,8 @@ pub fn do_env_test(cfg: &Config) -> DistResult<()> {
 
         match step {
             BuildStep::Cargo(step) => {
+                need_cargo = true;
+
                 let target = step.target_triple.parse()?;
                 let wrapper = tasks::build_wrapper_for_cross(&host, &target)?;
 
@@ -104,6 +107,7 @@ pub fn do_env_test(cfg: &Config) -> DistResult<()> {
     // bool::then(f) returns an Option, so we start with a
     // Vec<Option<Result<&Tool, DistResult>>>.
     let all_tools: Vec<Option<DistResult<&Tool>>> = vec![
+        need_cargo.then(|| tools.cargo_tool()),
         need_cargo_auditable.then(|| tools.cargo_auditable()),
         need_cargo_cyclonedx.then(|| tools.cargo_cyclonedx()),
         need_omnibor.then(|| tools.omnibor()),
diff --git a/cargo-dist/src/tasks.rs b/cargo-dist/src/tasks.rs
index 4c83ec88..2dfad37e 100644
--- a/cargo-dist/src/tasks.rs
+++ b/cargo-dist/src/tasks.rs
@@ -289,9 +289,20 @@ pub struct Tools {
     pub cargo_xwin: Option<Tool>,
     /// cargo-zigbuild, for some cross builds
     pub cargo_zigbuild: Option<Tool>,
+
+    // This is a kludge to avoid type issues. See cargo_tool() docs.
+    cargo_tool: Option<Tool>,
 }
 
 impl Tools {
+    /// Return the cargo info, as a Tool instead of a CargoInfo, or an error.
+    /// This is a kludge to avoid needing to handle type issues.
+    pub fn cargo_tool(&self) -> DistResult<&Tool> {
+        self.cargo_tool.as_ref().ok_or(DistError::ToolMissing {
+            tool: "cargo".to_owned(),
+        })
+    }
+
     /// Returns the cargo info or an error
     pub fn cargo(&self) -> DistResult<&CargoInfo> {
         self.cargo.as_ref().ok_or(DistError::ToolMissing {
@@ -3224,6 +3235,8 @@ fn tool_info() -> DistResult<Tools> {
         cargo_cyclonedx: find_cargo_subcommand("cargo", "cyclonedx", "--version"),
         cargo_xwin: find_cargo_subcommand("cargo", "xwin", "--version"),
         cargo_zigbuild: find_tool("cargo-zigbuild", "--version"),
+
+        cargo_tool: find_tool("cargo", "-V"),
     })
 }