Add GUI test to check ayu <code> colors

Author: GuillaumeGomez

src/test/rustdoc-gui/ayu-code-tag-colors.goml

@@ -0,0 +1,13 @@
+// The ayu theme has a different color for the "<code>" tags in the doc blocks. We need to
+// check that the rule isn't applied on other "<code>" elements.
+goto: file://|DOC_PATH|/test_docs/enum.AnEnum.html
+// We need to show the text, otherwise the colors aren't "computed" by the web browser.
+show-text: true
+// We set the theme to ayu.
+local-storage: {"rustdoc-theme": "ayu", "rustdoc-preferred-dark-theme": "ayu", "rustdoc-use-system-theme": "false"}
+// We reload to get the text appearing and the theme applied.
+reload:
+
+assert-css: (".docblock code", {"color": "rgb(255, 180, 84)"}, ALL)
+// It includes variants and the "titles" as well (for example: "impl RefUnwindSafe for AnEnum").
+assert-css: ("div:not(.docblock) > code", {"color": "rgb(197, 197, 197)"}, ALL)

src/test/rustdoc-gui/src/test_docs/lib.rs

@@ -96,6 +96,7 @@ pub fn check_list_code_block() {}
 #[doc(cfg(unix))]
 pub fn replaced_function() {}
 
+/// Some doc with `code`!
 pub enum AnEnum {
     WithVariants { and: usize, sub: usize, variants: usize },
 }