diff --git a/src/test/rustdoc-gui/default-settings.goml b/src/test/rustdoc-gui/default-settings.goml
new file mode 100644
index 00000000000..68b674a11f2
--- /dev/null
+++ b/src/test/rustdoc-gui/default-settings.goml
@@ -0,0 +1,8 @@
+// This test ensures that the default settings are correctly applied.
+//
+// The "settings" crate uses "ayu" as default setting, which is what we will
+// check.
+goto: file://|DOC_PATH|/settings/index.html
+// Wait a bit to be sure the default theme is applied.
+wait-for: 1000
+assert-css: ("body", {"background-color": "rgb(15, 20, 25)"})
diff --git a/src/test/rustdoc-gui/src/implementors/Cargo.lock b/src/test/rustdoc-gui/src/implementors/Cargo.lock
new file mode 100644
index 00000000000..cad99a991a2
--- /dev/null
+++ b/src/test/rustdoc-gui/src/implementors/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "implementors"
+version = "0.1.0"
diff --git a/src/test/rustdoc-gui/src/lib2/Cargo.lock b/src/test/rustdoc-gui/src/lib2/Cargo.lock
new file mode 100644
index 00000000000..a5873ceb325
--- /dev/null
+++ b/src/test/rustdoc-gui/src/lib2/Cargo.lock
@@ -0,0 +1,14 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "implementors"
+version = "0.1.0"
+
+[[package]]
+name = "lib2"
+version = "0.1.0"
+dependencies = [
+ "implementors",
+]
diff --git a/src/test/rustdoc-gui/src/settings/.cargo/config.toml b/src/test/rustdoc-gui/src/settings/.cargo/config.toml
new file mode 100644
index 00000000000..bbb8d11a2ed
--- /dev/null
+++ b/src/test/rustdoc-gui/src/settings/.cargo/config.toml
@@ -0,0 +1,2 @@
+[build]
+rustdocflags = ["--default-theme", "ayu"]
diff --git a/src/test/rustdoc-gui/src/settings/Cargo.lock b/src/test/rustdoc-gui/src/settings/Cargo.lock
new file mode 100644
index 00000000000..6f0de1ac1e8
--- /dev/null
+++ b/src/test/rustdoc-gui/src/settings/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "settings"
+version = "0.1.0"
diff --git a/src/test/rustdoc-gui/src/settings/Cargo.toml b/src/test/rustdoc-gui/src/settings/Cargo.toml
new file mode 100644
index 00000000000..c8a211a47ca
--- /dev/null
+++ b/src/test/rustdoc-gui/src/settings/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "settings"
+version = "0.1.0"
+edition = "2018"
+
+[lib]
+path = "lib.rs"
diff --git a/src/test/rustdoc-gui/src/settings/lib.rs b/src/test/rustdoc-gui/src/settings/lib.rs
new file mode 100644
index 00000000000..b76b4321d62
--- /dev/null
+++ b/src/test/rustdoc-gui/src/settings/lib.rs
@@ -0,0 +1 @@
+pub fn foo() {}
diff --git a/src/test/rustdoc-gui/src/test_docs/Cargo.lock b/src/test/rustdoc-gui/src/test_docs/Cargo.lock
new file mode 100644
index 00000000000..6b80f6e88ef
--- /dev/null
+++ b/src/test/rustdoc-gui/src/test_docs/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "test_docs"
+version = "0.1.0"
diff --git a/src/test/rustdoc/default-theme.rs b/src/test/rustdoc/default-theme.rs
new file mode 100644
index 00000000000..ecb8f0b3b48
--- /dev/null
+++ b/src/test/rustdoc/default-theme.rs
@@ -0,0 +1,7 @@
+// compile-flags: --default-theme ayu
+
+// @has default_theme/index.html
+// @has - '//script[@id="default-settings"]/@data-theme' 'ayu'
+// @has - '//script[@id="default-settings"]/@data-use_system_theme' 'false'
+
+pub fn whatever() {}