test generics highlight in doctest

Author: HKalbasi

crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html

@@ -106,6 +106,13 @@
     <span class="comment documentation">/// </span><span class="keyword injected">let</span><span class="none injected"> </span><span class="variable declaration injected">foobar</span><span class="none injected"> </span><span class="operator injected">=</span><span class="none injected"> </span><span class="struct injected">Foo</span><span class="operator injected">::</span><span class="function injected">new</span><span class="parenthesis injected">(</span><span class="parenthesis injected">)</span><span class="operator injected">.</span><span class="function injected">bar</span><span class="parenthesis injected">(</span><span class="parenthesis injected">)</span><span class="semicolon injected">;</span>
     <span class="comment documentation">/// ```</span>
     <span class="comment documentation">///</span>
+    <span class="comment documentation">/// ```</span>
+    <span class="comment documentation">/// </span><span class="comment injected">// functions</span>
+    <span class="comment documentation">/// </span><span class="keyword injected">fn</span><span class="none injected"> </span><span class="function declaration injected">foo</span><span class="angle injected">&lt;</span><span class="type_param declaration injected">T</span><span class="comma injected">,</span><span class="none injected"> </span><span class="keyword injected">const</span><span class="none injected"> </span><span class="const_param declaration injected">X</span><span class="colon injected">:</span><span class="none injected"> </span><span class="builtin_type injected">usize</span><span class="angle injected">&gt;</span><span class="parenthesis injected">(</span><span class="value_param declaration injected">arg</span><span class="colon injected">:</span><span class="none injected"> </span><span class="builtin_type injected">i32</span><span class="parenthesis injected">)</span><span class="none injected"> </span><span class="brace injected">{</span>
+    <span class="comment documentation">/// </span><span class="none injected">    </span><span class="keyword injected">let</span><span class="none injected"> </span><span class="variable declaration injected">x</span><span class="colon injected">:</span><span class="none injected"> </span><span class="type_param injected">T</span><span class="none injected"> </span><span class="operator injected">=</span><span class="none injected"> </span><span class="const_param injected">X</span><span class="semicolon injected">;</span>
+    <span class="comment documentation">/// </span><span class="brace injected">}</span>
+    <span class="comment documentation">/// ```</span>
+    <span class="comment documentation">/// </span>
     <span class="comment documentation">/// ```sh</span>
     <span class="comment documentation">/// echo 1</span>
     <span class="comment documentation">/// ```</span>

crates/ide/src/syntax_highlighting/tests.rs

@@ -696,6 +696,13 @@ impl Foo {
     /// let foobar = Foo::new().bar();
     /// ```
     ///
+    /// ```
+    /// // functions
+    /// fn foo<T, const X: usize>(arg: i32) {
+    ///     let x: T = X;
+    /// }
+    /// ```
+    /// 
     /// ```sh
     /// echo 1
     /// ```