docs: add example of minimal subplot using Rust step functions

Sponsored-by: author

4 files changed, 63 insertions, 0 deletions

diff --git a/examples/seq/Cargo.toml b/examples/seq/Cargo.toml
new file mode 100644
index 0000000..e0f577a
--- /dev/null
+++ b/examples/seq/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+name = "seq"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+subplotlib = { path = "../../subplotlib" }
+
+[build-dependencies]
+subplot-build = { path = "../../subplot-build" }
diff --git a/examples/seq/build.rs b/examples/seq/build.rs
new file mode 100644
index 0000000..398ec90
--- /dev/null
+++ b/examples/seq/build.rs
@@ -0,0 +1,6 @@
+//! Subplot seq example build script.
+
+fn main() {
+    println!("cargo:rerun-if-changed=seq.md");
+    subplot_build::codegen("seq.md").expect("failed to generate code with Subplot");
+}
diff --git a/examples/seq/seq.md b/examples/seq/seq.md
new file mode 100644
index 0000000..da51a3f
--- /dev/null
+++ b/examples/seq/seq.md
@@ -0,0 +1,44 @@
+---
+title: "**seq**(1) acceptance tests"
+author: The Subplot project
+bindings:
+- lib/runcmd.yaml
+impls:
+  rust: []
+...
+
+# Introduction
+
+**seq**(1) is a Unix command line tool that produces numbers 1, 2,
+etc, up until a count given by the user. For example, if the user runs
+`seq 3`, the output has the numbers 1, 2, and 3, one per line.
+
+# No arguments
+
+_Requirement: If `seq` is run without arguments, it reports an error._
+
+```scenario
+when I try to run seq
+then exit code is 1
+```
+
+# No numbers
+
+_Requirement: If `seq` is run with the argument 0, it writes nothing._
+
+```scenario
+when I run seq 0
+then stdout is exactly ""
+then stderr is exactly ""
+```
+
+# One number
+
+_Requirement: If `seq` is run with the argument 1, it writes one line,
+with the number 1._
+
+```scenario
+when I run seq 1
+then stdout is exactly "1\n"
+then stderr is exactly ""
+```
diff --git a/examples/seq/tests/seq.rs b/examples/seq/tests/seq.rs
new file mode 100644
index 0000000..5412848
--- /dev/null
+++ b/examples/seq/tests/seq.rs
@@ -0,0 +1 @@
+include!(concat!(env!("OUT_DIR"), "/seq.rs"));