Show definition for constants

Similar to the fix for functions in 1a242e5, we have to use a different
selector to query the definition for constants, "pre.const" instead of
".docblock.type-decl".

CHANGELOG.md

@@ -12,6 +12,7 @@ SPDX-License-Identifier: MIT
 - Improve the documentation parser:
   - Fix the definition of methods to only contain the actual definition.
   - Remove spurious members in module documentation.
+  - Show the definition for constants.
 
 ## v0.1.2 (2020-07-25)
 

src/parser.rs

@@ -129,10 +129,10 @@ fn get_example(node: &kuchiki::NodeRef) -> doc::Example {
 pub fn parse_item_doc(item: &doc::Item) -> anyhow::Result<doc::Doc> {
     log::info!("Parsing item documentation for '{}'", item.name);
     let document = parse_file(&item.path)?;
-    let definition_selector = if item.ty == doc::ItemType::Function {
-        "pre.fn"
-    } else {
-        ".docblock.type-decl"
+    let definition_selector = match item.ty {
+        doc::ItemType::Constant => "pre.const",
+        doc::ItemType::Function => "pre.fn",
+        _ => ".docblock.type-decl",
     };
     let definition = select_first(&document, definition_selector)?;
     let description = select_first(&document, "#main > .docblock:not(.type-decl)")?;