tidy now installs typos-cli as-needed via cargo

Author: lolbinarycat

src/build_helper/src/util.rs

@@ -1,6 +1,7 @@
+use std::env;
 use std::fs::File;
-use std::io::{BufRead, BufReader};
-use std::path::Path;
+use std::io::{self, BufRead, BufReader};
+use std::path::{Path, PathBuf};
 use std::process::Command;
 
 /// Invokes `build_helper::util::detail_exit` with `cfg!(test)`
@@ -66,3 +67,39 @@ pub fn parse_gitmodules(target_dir: &Path) -> Vec<String> {
 
     submodules_paths
 }
+
+/// If the given executible is installed with the given version, use that,
+/// otherwise install via cargo.
+pub fn ensure_version_or_cargo_install(
+    build_dir: &Path,
+    pkg_name: &str,
+    bin_name: &str,
+    version: &str,
+) -> io::Result<PathBuf> {
+    let tool_root_dir = build_dir.join("misc-tools");
+    let tool_bin_dir = tool_root_dir.join("bin");
+    // use --force to ensure that if the required version is bumped, we update it.
+    // use --target-dir to ensure we have a build cache so repeated invocations aren't slow.
+    // modify PATH so that cargo doesn't print a warning telling the user to modify the path.
+    let cargo_exit_code = Command::new("cargo")
+        .args(["install", "--locked", "--force", "--quiet"])
+        .arg("--root")
+        .arg(&tool_root_dir)
+        .arg("--target-dir")
+        .arg(tool_root_dir.join("target"))
+        .arg(format!("{pkg_name}@{version}"))
+        .env(
+            "PATH",
+            env::join_paths(
+                env::split_paths(&env::var("PATH").unwrap())
+                    .chain(std::iter::once(tool_bin_dir.clone())),
+            )
+            .expect("build dir contains invalid char"),
+        )
+        .spawn()?
+        .wait()?;
+    if !cargo_exit_code.success() {
+        return Err(io::Error::other("cargo install failed"));
+    }
+    return Ok(tool_bin_dir.join(bin_name));
+}

src/tools/tidy/src/extra_checks/mod.rs

@@ -23,6 +23,8 @@ use std::process::Command;
 use std::str::FromStr;
 use std::{fmt, fs, io};
 
+use build_helper::util::ensure_version_or_cargo_install;
+
 use crate::CiInfo;
 
 mod rustdoc_js;
@@ -293,7 +295,7 @@ fn check_impl(
         } else {
             eprintln!("spellcheck files");
         }
-        spellcheck_runner(&args)?;
+        spellcheck_runner(&outdir, &args)?;
     }
 
     if js_lint || js_typecheck {
@@ -577,32 +579,10 @@ fn shellcheck_runner(args: &[&OsStr]) -> Result<(), Error> {
 }
 
 /// Check that spellchecker is installed then run it at the given path
-fn spellcheck_runner(args: &[&str]) -> Result<(), Error> {
-    // sync version with .github/workflows/spellcheck.yml
-    let expected_version = "typos-cli 1.34.0";
-    match Command::new("typos").arg("--version").output() {
-        Ok(o) => {
-            let stdout = String::from_utf8_lossy(&o.stdout);
-            if stdout.trim() != expected_version {
-                return Err(Error::Version {
-                    program: "typos",
-                    required: expected_version,
-                    installed: stdout.trim().to_string(),
-                });
-            }
-        }
-        Err(e) if e.kind() == io::ErrorKind::NotFound => {
-            return Err(Error::MissingReq(
-                "typos",
-                "spellcheck file checks",
-                // sync version with .github/workflows/spellcheck.yml
-                Some("install tool via `cargo install [email protected]`".to_owned()),
-            ));
-        }
-        Err(e) => return Err(e.into()),
-    }
+fn spellcheck_runner(outdir: &Path, args: &[&str]) -> Result<(), Error> {
+    let bin_path = ensure_version_or_cargo_install(outdir, "typos-cli", "typos", "1.34.0")?;
 
-    let status = Command::new("typos").args(args).status()?;
+    let status = Command::new(bin_path).args(args).status()?;
     if status.success() { Ok(()) } else { Err(Error::FailedCheck("typos")) }
 }