modules: Add an unstable-rust module

Like other language specific modules this module is module for holding
rust specific helpers. This commit adds a test() function, which
simplifies using rust's internal unittest mechanism.

Rust tests are generally placed in the same code files as they are
testing, in contrast to languages like C/C++ and python which generally
place the tests in separate translation units. For meson this is
somewhat problematic from a repetition point of view, as the only
changes are generally adding --test, and possibly some dependencies.

The rustmod.test() method provides a mechanism to remove the repatition:
it takes a rust target, copies it, and then addes the `--test` option,
then creates a Test() target with the `rust` protocol. You can pass
additional dependencies via the `dependencies` keyword. This all makes
for a nice, DRY, test definition.

5 files changed, 69 insertions, 27 deletions

diff --git a/docs/markdown/Rust-module.md b/docs/markdown/Rust-module.md
new file mode 100644
index 0000000..0fdba94
--- /dev/null
+++ b/docs/markdown/Rust-module.md
@@ -0,0 +1,35 @@
+---
+short-description: Rust language integration module
+authors:
+    - name: Dylan Baker
+      email: dylan@pnwbakers.com
+      years: [2020]
+...
+
+# Unstable Rust module
+
+*(new in 0.57.0)*
+
+**Note** Unstable modules make no backwards compatible API guarantees.
+
+The rust module provides helper to integrate rust code into meson. The goal
+is to make using rust in meson more pleasant, while still remaining mesonic,
+this means that it attempts to make rust work more like meson, rather than
+meson work more like rust.
+
+## Functions
+
+### test(name: string, target: library | executable, dependencies: []Dependency)
+
+This function creates a new rust unittest target from an existing rust based
+target, which may be a library or executable. It does this by copying the
+sources and arguments passed to the original target and adding the `--test`
+argument to the compilation, then creates a new test target which calls that
+executable, using the rust test protocol.
+
+This accepts all of the keyword arguments as the
+[`test`](Reference-manual.md#test) function except `protocol`, it will set
+that automatically.
+
+Additional, test only dependencies may be passed via the dependencies
+argument.
diff --git a/docs/markdown/_Sidebar.md b/docs/markdown/_Sidebar.md
index 2637d68..0ca1762 100644
--- a/docs/markdown/_Sidebar.md
+++ b/docs/markdown/_Sidebar.md
@@ -12,3 +12,4 @@
 * [gnome](Gnome-module.md)
 * [i18n](i18n-module.md)
 * [pkgconfig](Pkgconfig-module.md)
+* [rust](Rust-module.md)
diff --git a/docs/markdown/snippets/unstable-rust-module.md b/docs/markdown/snippets/unstable-rust-module.md
new file mode 100644
index 0000000..15a7ecb
--- /dev/null
+++ b/docs/markdown/snippets/unstable-rust-module.md
@@ -0,0 +1,4 @@
+## Untable Rust module
+
+A new unstable module has been added to make using rust with meson easier.
+Currently it adds a single function to ease defining rust tests.
diff --git a/docs/sitemap.txt b/docs/sitemap.txt
index 4cae9fe..3164440 100644
--- a/docs/sitemap.txt
+++ b/docs/sitemap.txt
@@ -34,24 +34,25 @@ index.md
 		Disabler.md
 		Modules.md
 			CMake-module.md
+			Cuda-module.md
 			Dlang-module.md
+			External-Project-module.md
 			Fs-module.md
 			Gnome-module.md
 			Hotdoc-module.md
-			i18n-module.md
 			Icestorm-module.md
+			Keyval-module.md
 			Pkgconfig-module.md
-			Python-module.md
 			Python-3-module.md
+			Python-module.md
 			Qt4-module.md
 			Qt5-module.md
 			RPM-module.md
+			Rust-module.md
 			Simd-module.md
 			SourceSet-module.md
 			Windows-module.md
-			Cuda-module.md
-			Keyval-module.md
-			External-Project-module.md
+			i18n-module.md
 		Java.md
 		Vala.md
 		D.md
diff --git a/docs/theme/extra/templates/navbar_links.html b/docs/theme/extra/templates/navbar_links.html
index 832bd2c..8df082f 100644
--- a/docs/theme/extra/templates/navbar_links.html
+++ b/docs/theme/extra/templates/navbar_links.html
@@ -5,28 +5,29 @@
     Modules <span class="caret"></span>
   </a>
   <ul class="dropdown-menu" id="modules-menu">
-    @for tup in ( \
-					 ("CMake-module.html","CMake"), \
-					 ("Cuda-module.html","CUDA"), \
-           ("Dlang-module.html","Dlang"), \
-           ("Fs-module.html","Filesystem"), \
-					 ("Gnome-module.html","GNOME"), \
-					 ("Hotdoc-module.html","Hotdoc"), \
-					 ("i18n-module.html","i18n"), \
-					 ("Icestorm-module.html","Icestorm"), \
-					 ("Keyval-module.html","Keyval"), \
-           ("Pkgconfig-module.html","Pkgconfig"), \
-           ("Python-module.html","Python"), \
-           ("Python-3-module.html","Python 3"), \
-           ("Qt4-module.html","Qt4"), \
-           ("Qt5-module.html","Qt5"), \
-           ("RPM-module.html","RPM"), \
-           ("SourceSet-module.html","SourceSet"), \
-           ("Windows-module.html","Windows")):
-			<li>
-				<a href="@tup[0]">@tup[1]</a>
-			</li>
-		@end
+    @for tup in [ \
+            ("CMake-module.html","CMake"), \
+            ("Cuda-module.html","CUDA"), \
+            ("Dlang-module.html","Dlang"), \
+            ("Fs-module.html","Filesystem"), \
+            ("Gnome-module.html","GNOME"), \
+            ("Hotdoc-module.html","Hotdoc"), \
+            ("Icestorm-module.html","Icestorm"), \
+            ("Keyval-module.html","Keyval"), \
+            ("Pkgconfig-module.html","Pkgconfig"), \
+            ("Python-3-module.html","Python 3"), \
+            ("Python-module.html","Python"), \
+            ("Qt4-module.html","Qt4"), \
+            ("Qt5-module.html","Qt5"), \
+            ("RPM-module.html","RPM"), \
+            ("Rust-module.html","Rust"), \
+            ("SourceSet-module.html","SourceSet"), \
+            ("Windows-module.html","Windows"), \
+            ("i18n-module.html","i18n")]:
+        <li>
+            <a href="@tup[0]">@tup[1]</a>
+        </li>
+    @end
 	</ul>
 </li>
 \