cucumber does stuff

members/cucumber-demo/Cargo.toml

@@ -5,4 +5,11 @@ edition = "2021"
 
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
-[dependencies]
+[dev-dependencies]
+futures = "0.3.30"
+cucumber = "0.20.2"
+tokio = { version = "1.10", features = ["macros", "rt-multi-thread", "time"] }
+
+[[test]]
+name = "example" # this should be the same as the filename of your test target
+harness = false  # allows Cucumber to print output instead of libtest

members/cucumber-demo/src/lib.rs

@@ -0,0 +1 @@
+// see tests/example.rs

members/cucumber-demo/src/main.rs

@@ -1,3 +0,0 @@
-fn main() {
-    println!("Hello, world!");
-}

members/cucumber-demo/tests/example.rs

@@ -0,0 +1,58 @@
+use cucumber::{given, then, when, World};
+
+// These `Cat` definitions would normally be inside your project's code,
+// not test code, but we create them here for the show case.
+#[derive(Debug, Default)]
+struct Cat {
+    pub hungry: bool,
+}
+
+impl Cat {
+    fn feed(&mut self) {
+        self.hungry = false;
+    }
+}
+
+// `World` is your shared, likely mutable state.
+// Cucumber constructs it via `Default::default()` for each scenario.
+#[derive(Debug, World)]
+// Accepts both sync/async and fallible/infallible functions.
+// We can set a non default constructor like this vvvv
+#[world(init = Self::new)]
+pub struct AnimalWorld {
+    cat: Cat,
+}
+
+// new constructor
+impl AnimalWorld {
+    fn new() -> Self {
+        Self {
+            cat: Cat { hungry: true },
+        }
+    }
+}
+
+// Steps are defined with `given`, `when` and `then` attributes.
+#[given(regex = r"^a (hungry|satiated) cat$")]
+async fn hungry_cat(world: &mut AnimalWorld, state: String) {
+    match state.as_str() {
+        "hungry" =>  world.cat.hungry = true,
+        "satiated" =>  world.cat.hungry = false,
+        _ => unreachable!(),
+    }
+}
+
+#[when("I feed the cat")]
+async fn feed_cat(world: &mut AnimalWorld) {
+    world.cat.feed();
+}
+
+#[then("the cat is not hungry")]
+async fn cat_is_fed(world: &mut AnimalWorld) {
+    assert!(!world.cat.hungry);
+}
+
+#[tokio::main]
+async fn main() {
+    futures::executor::block_on(AnimalWorld::run("tests/features/book/animal.feature"));
+}

members/cucumber-demo/tests/features/book/animal.feature

@@ -0,0 +1,11 @@
+Feature: Animal feature
+
+  Scenario: If we feed a hungry cat it will no longer be hungry
+    Given a hungry cat
+    When I feed the cat
+    Then the cat is not hungry
+
+  Scenario: If we feed a satiated cat it will not become hungry
+    Given a satiated cat
+    When I feed the cat
+    Then the cat is not hungry