diff --git a/src/bootstrap/builder.rs b/src/bootstrap/builder.rs
index 6de3746363337..406bae02d84da 100644
--- a/src/bootstrap/builder.rs
+++ b/src/bootstrap/builder.rs
@@ -2207,6 +2207,24 @@ impl<'a> Builder<'a> {
 
         false
     }
+
+    pub(crate) fn maybe_open_in_browser<S: Step>(&self, path: impl AsRef<Path>) {
+        if self.was_invoked_explicitly::<S>(Kind::Doc) {
+            self.open_in_browser(path);
+        }
+    }
+
+    pub(crate) fn open_in_browser(&self, path: impl AsRef<Path>) {
+        if self.config.dry_run || !self.config.cmd.open() {
+            return;
+        }
+
+        let path = path.as_ref();
+        self.info(&format!("Opening doc {}", path.display()));
+        if let Err(err) = opener::open(path) {
+            self.info(&format!("{}\n", err));
+        }
+    }
 }
 
 #[cfg(test)]
diff --git a/src/bootstrap/doc.rs b/src/bootstrap/doc.rs
index 5d265b9ad0c19..1357718b84e35 100644
--- a/src/bootstrap/doc.rs
+++ b/src/bootstrap/doc.rs
@@ -85,18 +85,6 @@ book!(
     StyleGuide, "src/doc/style-guide", "style-guide";
 );
 
-fn open(builder: &Builder<'_>, path: impl AsRef<Path>) {
-    if builder.config.dry_run || !builder.config.cmd.open() {
-        return;
-    }
-
-    let path = path.as_ref();
-    builder.info(&format!("Opening doc {}", path.display()));
-    if let Err(err) = opener::open(path) {
-        builder.info(&format!("{}\n", err));
-    }
-}
-
 // "library/std" -> ["library", "std"]
 //
 // Used for deciding whether a particular step is one requested by the user on
@@ -240,11 +228,9 @@ impl Step for TheBook {
             invoke_rustdoc(builder, compiler, &shared_assets, target, path);
         }
 
-        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
-            let out = builder.doc_out(target);
-            let index = out.join("book").join("index.html");
-            open(builder, &index);
-        }
+        let out = builder.doc_out(target);
+        let index = out.join("book").join("index.html");
+        builder.maybe_open_in_browser::<Self>(index);
     }
 }
 
@@ -386,7 +372,7 @@ impl Step for Standalone {
         // with no particular explicit doc requested (e.g. library/core).
         if builder.paths.is_empty() || builder.was_invoked_explicitly::<Self>(Kind::Doc) {
             let index = out.join("index.html");
-            open(builder, &index);
+            builder.open_in_browser(&index);
         }
     }
 }
@@ -507,7 +493,7 @@ impl Step for Std {
         for requested_crate in requested_crates {
             if STD_PUBLIC_CRATES.iter().any(|k| *k == requested_crate.as_str()) {
                 let index = out.join(requested_crate).join("index.html");
-                open(builder, &index);
+                builder.open_in_browser(index);
             }
         }
     }
@@ -759,7 +745,7 @@ impl Step for Rustc {
         // Let's open the first crate documentation page:
         if let Some(krate) = to_open {
             let index = out.join(krate).join("index.html");
-            open(builder, &index);
+            builder.open_in_browser(index);
         }
     }
 }
@@ -1019,10 +1005,9 @@ impl Step for RustcBook {
             name: INTERNER.intern_str("rustc"),
             src: INTERNER.intern_path(out_base),
         });
-        if builder.was_invoked_explicitly::<Self>(Kind::Doc) {
-            let out = builder.doc_out(self.target);
-            let index = out.join("rustc").join("index.html");
-            open(builder, &index);
-        }
+
+        let out = builder.doc_out(self.target);
+        let index = out.join("rustc").join("index.html");
+        builder.maybe_open_in_browser::<Self>(index);
     }
 }