Document ShouldRun::paths

Author: jyn514

src/bootstrap/builder.rs

@@ -473,7 +473,15 @@ impl<'a> ShouldRun<'a> {
         self.paths(&[path])
     }
 
-    // multiple aliases for the same job
+    /// Multiple aliases for the same job.
+    ///
+    /// This differs from [`path`] in that multiple calls to path will end up calling `make_run`
+    /// multiple times, whereas a single call to `paths` will only ever generate a single call to
+    /// `paths`.
+    ///
+    /// This is analogous to `all_krates`, although `all_krates` is gone now. Prefer [`path`] where possible.
+    ///
+    /// [`path`]: ShouldRun::path
     pub fn paths(mut self, paths: &[&str]) -> Self {
         static SUBMODULES_PATHS: OnceCell<Vec<String>> = OnceCell::new();