Update the README and CHANGELOG

CHANGELOG.md

@@ -15,6 +15,10 @@
 - a `StringBuilder` struct that can be used to incrementally build
   `nvim_oxi::String`s;
 
+- a `nvim_oxi::tests::build()` function to be used in the build script of
+  a crate containing integration tests annotated with `#[nvim_oxi::test]`
+  ([#201](https://github.com/noib3/nvim-oxi/pull/201));
+
 ### Changed
 
 - `nvim_oxi::api::echo` is now generic over the highlight group type instead of

README.md

@@ -60,31 +60,28 @@ might add a new example documenting your use case (if it can be done).
 
 ## Testing
 
-The `test` feature flag enables the `#[nvim_oxi::test]` proc macro. This macro
-replaces the regular `#[test]` annotations and can be used to test a piece of
-code from within a Neovim instance using Rust's excellent testing framework.
+Turning on the `test` feature enables `#[nvim_oxi::test]`, which replaces the
+regular `#[test]` macro and allows you to test a piece of code from within a
+Neovim instance using Rust's testing framework.
 
 For example:
 
 ```rust
-use nvim_oxi::{self as oxi, api};
+use nvim_oxi::api;
 
-#[oxi::test]
+#[nvim_oxi::test]
 fn set_get_del_var() {
     api::set_var("foo", 42).unwrap();
     assert_eq!(Ok(42), api::get_var("foo"));
     assert_eq!(Ok(()), api::del_var("foo"));
 }
 ```
 
-Then `cargo test` will spawn a new Neovim process with an empty config, run
-that code and exit. There are a couple of gotchas:
+When `cargo test` is executed, the generated code will spawn a new Neovim
+process with the `nvim` binary in your `$PATH`, test your code, and exit.
 
-- after changing a piece of code, `cargo build` has to be run before you can
-  test that with `cargo test`;
-
-- you cannot have two test functions with the same name, even if they belong to
-  different modules. For example this won't work:
+There's a gotcha: you can't have two tests with the same name in the same
+crate, even if they belong to different modules. For example, this won't work:
 
 ```rust
 mod a {
@@ -97,3 +94,13 @@ mod b {
     fn foo() {}
 }
 ```
+
+Note that all integration tests must live inside a separate `cdylib` crate with
+the following build script:
+
+```rust
+// build.rs
+fn main() -> Result<(), nvim_oxi::tests::BuildError> {
+    nvim_oxi::tests::build()
+}
+```