diff --git a/tests/source/chains_with_comment.rs b/tests/source/chains_with_comment.rs
new file mode 100644
index 00000000000..80c118d9ecc
--- /dev/null
+++ b/tests/source/chains_with_comment.rs
@@ -0,0 +1,95 @@
+// Chains with comment.
+
+fn main() {
+    let x = y // comment
+        .z;
+
+    foo // foo
+        // comment after parent
+        .x
+        .y
+        // comment 1
+        .bar() // comment after bar()
+  // comment 2
+        .foobar
+  // comment after
+        // comment 3
+        .baz(x, y, z);
+
+    self.rev_dep_graph
+        .iter()
+       // Remove nodes that are not dirty
+        .filter(|&(unit, _)| dirties.contains(&unit))
+     // Retain only dirty dependencies of the ones that are dirty
+       .map(|(k, deps)| {
+            (
+                k.clone(),
+                deps.iter()
+                .cloned()
+               .filter(|d| dirties.contains(&d))
+              .collect(),
+            )
+        });
+
+    let y = expr /* comment */.kaas()?
+// comment
+       .test();
+    let loooooooooooooooooooooooooooooooooooooooooong = does_this?.look?.good?.should_we_break?.after_the_first_question_mark?;
+    let zzzz = expr?   // comment after parent
+// comment 0
+.another??? // comment 1
+.another????  // comment 2
+.another? // comment 3
+.another?;
+
+    let y = a.very .loooooooooooooooooooooooooooooooooooooong() /* comment */ .chain()
+        .inside()  /* comment */        .weeeeeeeeeeeeeee()? .test()  .0
+        .x;
+
+    parameterized(f,
+                  substs,
+                  def_id,
+                  Ns::Value,
+                  &[],
+                  |tcx| tcx.lookup_item_type(def_id).generics)?;
+    fooooooooooooooooooooooooooo()?.bar()?.baaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaz()?;
+
+    // #2559
+    App::new("cargo-cache")
+.version(crate_version!())
+.bin_name("cargo")
+.about("Manage cargo cache")
+.author("matthiaskrgr")
+.subcommand(
+SubCommand::with_name("cache")
+.version(crate_version!())
+.bin_name("cargo-cache")
+.about("Manage cargo cache")
+.author("matthiaskrgr")
+.arg(&list_dirs)
+.arg(&remove_dir)
+.arg(&gc_repos)
+.arg(&info)
+.arg(&keep_duplicate_crates)    .arg(&dry_run)
+.arg(&auto_clean)
+.arg(&auto_clean_expensive),
+        ) // subcommand
+        .arg(&list_dirs);
+}
+
+// #2177
+impl Foo {
+    fn dirty_rev_dep_graph(
+        &self,
+        dirties: &HashSet<UnitKey>,
+    ) -> HashMap<UnitKey, HashSet<UnitKey>> {
+        let dirties = self.transitive_dirty_units(dirties);
+        trace!("transitive_dirty_units: {:?}", dirties);
+
+        self.rev_dep_graph.iter()
+        // Remove nodes that are not dirty
+            .filter(|&(unit, _)| dirties.contains(&unit))
+        // Retain only dirty dependencies of the ones that are dirty
+            .map(|(k, deps)| (k.clone(), deps.iter().cloned().filter(|d| dirties.contains(&d)).collect()))
+    }
+}
diff --git a/tests/target/chains_with_comment.rs b/tests/target/chains_with_comment.rs
new file mode 100644
index 00000000000..a1df2710234
--- /dev/null
+++ b/tests/target/chains_with_comment.rs
@@ -0,0 +1,118 @@
+// Chains with comment.
+
+fn main() {
+    let x = y // comment
+        .z;
+
+    foo // foo
+        // comment after parent
+        .x
+        .y
+        // comment 1
+        .bar() // comment after bar()
+        // comment 2
+        .foobar
+        // comment after
+        // comment 3
+        .baz(x, y, z);
+
+    self.rev_dep_graph
+        .iter()
+        // Remove nodes that are not dirty
+        .filter(|&(unit, _)| dirties.contains(&unit))
+        // Retain only dirty dependencies of the ones that are dirty
+        .map(|(k, deps)| {
+            (
+                k.clone(),
+                deps.iter()
+                    .cloned()
+                    .filter(|d| dirties.contains(&d))
+                    .collect(),
+            )
+        });
+
+    let y = expr
+        /* comment */
+        .kaas()?
+        // comment
+        .test();
+    let loooooooooooooooooooooooooooooooooooooooooong = does_this?
+        .look?
+        .good?
+        .should_we_break?
+        .after_the_first_question_mark?;
+    let zzzz = expr? // comment after parent
+        // comment 0
+        .another??? // comment 1
+        .another???? // comment 2
+        .another? // comment 3
+        .another?;
+
+    let y = a
+        .very
+        .loooooooooooooooooooooooooooooooooooooong()
+        /* comment */
+        .chain()
+        .inside()
+        /* comment */
+        .weeeeeeeeeeeeeee()?
+        .test()
+        .0
+        .x;
+
+    parameterized(f, substs, def_id, Ns::Value, &[], |tcx| {
+        tcx.lookup_item_type(def_id).generics
+    })?;
+    fooooooooooooooooooooooooooo()?
+        .bar()?
+        .baaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaz()?;
+
+    // #2559
+    App::new("cargo-cache")
+        .version(crate_version!())
+        .bin_name("cargo")
+        .about("Manage cargo cache")
+        .author("matthiaskrgr")
+        .subcommand(
+            SubCommand::with_name("cache")
+                .version(crate_version!())
+                .bin_name("cargo-cache")
+                .about("Manage cargo cache")
+                .author("matthiaskrgr")
+                .arg(&list_dirs)
+                .arg(&remove_dir)
+                .arg(&gc_repos)
+                .arg(&info)
+                .arg(&keep_duplicate_crates)
+                .arg(&dry_run)
+                .arg(&auto_clean)
+                .arg(&auto_clean_expensive),
+        ) // subcommand
+        .arg(&list_dirs);
+}
+
+// #2177
+impl Foo {
+    fn dirty_rev_dep_graph(
+        &self,
+        dirties: &HashSet<UnitKey>,
+    ) -> HashMap<UnitKey, HashSet<UnitKey>> {
+        let dirties = self.transitive_dirty_units(dirties);
+        trace!("transitive_dirty_units: {:?}", dirties);
+
+        self.rev_dep_graph
+            .iter()
+            // Remove nodes that are not dirty
+            .filter(|&(unit, _)| dirties.contains(&unit))
+            // Retain only dirty dependencies of the ones that are dirty
+            .map(|(k, deps)| {
+                (
+                    k.clone(),
+                    deps.iter()
+                        .cloned()
+                        .filter(|d| dirties.contains(&d))
+                        .collect(),
+                )
+            })
+    }
+}