diff --git a/src/test/rustdoc-json/reexport/glob_extern.rs b/src/test/rustdoc-json/reexport/glob_extern.rs
new file mode 100644
index 0000000000000..831c185f6b136
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/glob_extern.rs
@@ -0,0 +1,17 @@
+// edition:2018
+
+#![no_core]
+#![feature(no_core)]
+
+// @!has glob_extern.json "$.index[*][?(@.name=='mod1')]"
+mod mod1 {
+    extern "C" {
+        // @set public_fn_id = - "$.index[*][?(@.name=='public_fn')].id"
+        pub fn public_fn();
+        // @!has - "$.index[*][?(@.name=='private_fn')]"
+        fn private_fn();
+    }
+}
+
+// @has - "$.index[*][?(@.name=='glob_extern')].inner.items[*]" $public_fn_id
+pub use mod1::*;
diff --git a/src/test/rustdoc-json/reexport/glob_private.rs b/src/test/rustdoc-json/reexport/glob_private.rs
new file mode 100644
index 0000000000000..e907de9236776
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/glob_private.rs
@@ -0,0 +1,27 @@
+// edition:2018
+
+#![no_core]
+#![feature(no_core)]
+
+// @!has glob_private.json "$.index[*][?(@.name=='mod1')]"
+mod mod1 {
+    // @!has - "$.index[*][?(@.name=='mod2')]"
+    mod mod2 {
+        // @set m2pub_id = - "$.index[*][?(@.name=='Mod2Public')].id"
+        pub struct Mod2Public;
+
+        // @!has - "$.index[*][?(@.name=='Mod2Private')]"
+        struct Mod2Private;
+    }
+    pub use self::mod2::*;
+
+    // @set m1pub_id = - "$.index[*][?(@.name=='Mod1Public')].id"
+    pub struct Mod1Public;
+
+    // @!has - "$.index[*][?(@.name=='Mod1Private')]"
+    struct Mod1Private;
+}
+pub use mod1::*;
+
+// @has - "$.index[*][?(@.name=='glob_private')].inner.items[*]" $m2pub_id
+// @has - "$.index[*][?(@.name=='glob_private')].inner.items[*]" $m1pub_id
diff --git a/src/test/rustdoc-json/reexport/rename_public.rs b/src/test/rustdoc-json/reexport/rename_public.rs
new file mode 100644
index 0000000000000..8c2d7200d0c01
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/rename_public.rs
@@ -0,0 +1,17 @@
+// edition:2018
+
+#![no_core]
+#![feature(no_core)]
+
+// @set inner_id = rename_public.json "$.index[*][?(@.name=='inner')].id"
+// @has - "$.index[*][?(@.name=='rename_public')].inner.items[*]" $inner_id
+pub mod inner {
+    // @set public_id = - "$.index[*][?(@.name=='Public')].id"
+    // @has - "$.index[*][?(@.name=='inner')].inner.items[*]" $public_id
+    pub struct Public;
+}
+// @set import_id = - "$.index[*][?(@.inner.name=='NewName')].id"
+// @!has - "$.index[*][?(@.inner.name=='Public')]"
+// @has - "$.index[*][?(@.name=='rename_public')].inner.items[*]" $import_id
+// @is - "$.index[*][?(@.inner.name=='NewName')].inner.span" \"inner::Public\"
+pub use inner::Public as NewName;
diff --git a/src/test/rustdoc-json/reexport/simple_private.rs b/src/test/rustdoc-json/reexport/simple_private.rs
new file mode 100644
index 0000000000000..658b121e6ce97
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/simple_private.rs
@@ -0,0 +1,13 @@
+// edition:2018
+
+#![no_core]
+#![feature(no_core)]
+
+// @!has simple_private.json "$.index[*][?(@.name=='inner')]"
+mod inner {
+    // @set pub_id = - "$.index[*][?(@.name=='Public')].id"
+    pub struct Public;
+}
+
+// @has - "$.index[*][?(@.name=='simple_private')].inner.items[*]" $pub_id
+pub use inner::Public;
diff --git a/src/test/rustdoc-json/reexport/simple_public.rs b/src/test/rustdoc-json/reexport/simple_public.rs
new file mode 100644
index 0000000000000..0c97a2e7b40a2
--- /dev/null
+++ b/src/test/rustdoc-json/reexport/simple_public.rs
@@ -0,0 +1,18 @@
+// edition:2018
+
+#![no_core]
+#![feature(no_core)]
+
+// @set inner_id = simple_public.json "$.index[*][?(@.name=='inner')].id"
+// @has - "$.index[*][?(@.name=='simple_public')].inner.items[*]" $inner_id
+pub mod inner {
+
+    // @set public_id = - "$.index[*][?(@.name=='Public')].id"
+    // @has - "$.index[*][?(@.name=='inner')].inner.items[*]" $public_id
+    pub struct Public;
+}
+
+// @set import_id = - "$.index[*][?(@.inner.name=='Public')].id"
+// @has - "$.index[*][?(@.name=='simple_public')].inner.items[*]" $import_id
+// @is - "$.index[*][?(@.inner.name=='Public')].inner.span" \"inner::Public\"
+pub use inner::Public;
diff --git a/src/tools/jsondocck/src/main.rs b/src/tools/jsondocck/src/main.rs
index 5020a4917a00a..bcb3f6922efaa 100644
--- a/src/tools/jsondocck/src/main.rs
+++ b/src/tools/jsondocck/src/main.rs
@@ -205,7 +205,21 @@ fn check_command(command: Command, cache: &mut Cache) -> Result<(), CkError> {
                     let val = cache.get_value(&command.args[0])?;
                     let results = select(&val, &command.args[1]).unwrap();
                     let pat = string_to_value(&command.args[2], cache);
-                    results.contains(&pat.as_ref())
+                    let has = results.contains(&pat.as_ref());
+                    // Give better error for when @has check fails
+                    if !command.negated && !has {
+                        return Err(CkError::FailedCheck(
+                            format!(
+                                "{} matched to {:?} but didn't have {:?}",
+                                &command.args[1],
+                                results,
+                                pat.as_ref()
+                            ),
+                            command,
+                        ));
+                    } else {
+                        has
+                    }
                 }
                 _ => unreachable!(),
             }
@@ -233,7 +247,13 @@ fn check_command(command: Command, cache: &mut Cache) -> Result<(), CkError> {
             assert_eq!(command.args[1], "=", "Expected an `=`");
             let val = cache.get_value(&command.args[2])?;
             let results = select(&val, &command.args[3]).unwrap();
-            assert_eq!(results.len(), 1);
+            assert_eq!(
+                results.len(),
+                1,
+                "Didn't get 1 result for `{}`: got {:?}",
+                command.args[3],
+                results
+            );
             match results.len() {
                 0 => false,
                 1 => {