fix: cache key dependency on installed packages (#138)

Add the installed packages to the environment element of the cache key
so that CI tooling is considered. This ensures that rust CI tooling is
cached correctly when changes occur. Prior to this a manual key change
or cache expiry would need to occur before CI tools were correctly
cached.

README.md

@@ -95,6 +95,7 @@ This cache is automatically keyed by:
 - the value of some compiler-specific environment variables (eg. RUSTFLAGS, etc), and
 - a hash of all `Cargo.lock` / `Cargo.toml` files found anywhere in the repository (if present).
 - a hash of all `rust-toolchain` / `rust-toolchain.toml` files in the root of the repository (if present).
+- a hash of installed packages as generated by `cargo install --list`.
 
 An additional input `key` can be provided if the builtin keys are not sufficient.
 

dist/restore/index.js

@@ -60055,6 +60055,9 @@ class CacheConfig {
             }
         }
         self.keyEnvs = keyEnvs;
+        // Installed packages and their versions are also considered for the key.
+        const packages = await getPackages();
+        hasher.update(packages);
         key += `-${hasher.digest("hex")}`;
         self.restoreKey = key;
         // Construct the lockfiles portion of the key:
@@ -60146,6 +60149,11 @@ async function getRustVersion() {
         .filter((s) => s.length === 2);
     return Object.fromEntries(splits);
 }
+async function getPackages() {
+    let stdout = await getCmdOutput("cargo", ["install", "--list"]);
+    // Make OS independent.
+    return stdout.split(/[\n\r]+/).join("\n");
+}
 async function globFiles(pattern) {
     const globber = await glob.create(pattern, {
         followSymbolicLinks: false,

dist/save/index.js

@@ -60055,6 +60055,9 @@ class CacheConfig {
             }
         }
         self.keyEnvs = keyEnvs;
+        // Installed packages and their versions are also considered for the key.
+        const packages = await getPackages();
+        hasher.update(packages);
         key += `-${hasher.digest("hex")}`;
         self.restoreKey = key;
         // Construct the lockfiles portion of the key:
@@ -60146,6 +60149,11 @@ async function getRustVersion() {
         .filter((s) => s.length === 2);
     return Object.fromEntries(splits);
 }
+async function getPackages() {
+    let stdout = await getCmdOutput("cargo", ["install", "--list"]);
+    // Make OS independent.
+    return stdout.split(/[\n\r]+/).join("\n");
+}
 async function globFiles(pattern) {
     const globber = await glob.create(pattern, {
         followSymbolicLinks: false,

src/config.ts

@@ -103,6 +103,11 @@ export class CacheConfig {
     }
 
     self.keyEnvs = keyEnvs;
+
+    // Installed packages and their versions are also considered for the key.
+    const packages = await getPackages();
+    hasher.update(packages);
+
     key += `-${hasher.digest("hex")}`;
 
     self.restoreKey = key;
@@ -220,6 +225,12 @@ async function getRustVersion(): Promise<RustVersion> {
   return Object.fromEntries(splits);
 }
 
+async function getPackages(): Promise<string> {
+  let stdout = await getCmdOutput("cargo", ["install", "--list"]);
+  // Make OS independent.
+  return stdout.split(/[\n\r]+/).join("\n");
+}
+
 async function globFiles(pattern: string): Promise<string[]> {
   const globber = await glob.create(pattern, {
     followSymbolicLinks: false,