feat! add subcommand "spec"

Sponsored-by: author

2 files changed, 27 insertions, 8 deletions

diff --git a/obnam-benchmark.md b/obnam-benchmark.md
index e80ae91..076255d 100644
--- a/obnam-benchmark.md
+++ b/obnam-benchmark.md
@@ -89,7 +89,7 @@ correctly.
 given an installed Rust program obnam-benchmark
 given file spec.yaml
 given file expected.json
-when I run obnam-benchmark spec.yaml --output spec.json
+when I run obnam-benchmark spec spec.yaml --output spec.json
 then JSON files spec.yaml and expected.json match
 ```
 
diff --git a/src/bin/obnam-benchmark.rs b/src/bin/obnam-benchmark.rs
index 617a0a3..5d4f06a 100644
--- a/src/bin/obnam-benchmark.rs
+++ b/src/bin/obnam-benchmark.rs
@@ -6,6 +6,17 @@ use structopt::StructOpt;
 
 #[derive(Debug, StructOpt)]
 struct Opt {
+    #[structopt(subcommand)]
+    cmd: Command,
+}
+
+#[derive(Debug, StructOpt)]
+enum Command {
+    Spec(Spec),
+}
+
+#[derive(Debug, StructOpt)]
+struct Spec {
     #[structopt(parse(from_os_str))]
     spec: PathBuf,
 
@@ -23,13 +34,21 @@ fn main() {
 fn real_main() -> anyhow::Result<()> {
     let opt = Opt::from_args();
 
-    println!("reading {}", opt.spec.display());
-    let input = File::open(&opt.spec)?;
-    let spec: Specification = serde_yaml::from_reader(&input)?;
-
-    println!("writing {}", opt.output.display());
-    let output = File::create(&opt.output)?;
-    serde_json::to_writer(&output, &spec)?;
+    match opt.cmd {
+        Command::Spec(x) => x.run()?,
+    }
 
     Ok(())
 }
+
+impl Spec {
+    fn run(&self) -> anyhow::Result<()> {
+        let input = File::open(&self.spec)?;
+        let spec: Specification = serde_yaml::from_reader(&input)?;
+
+        let output = File::create(&self.output)?;
+        serde_json::to_writer(&output, &spec)?;
+
+        Ok(())
+    }
+}