[functional-tests] port thin_delta tests to rust.

cargo test

tests/thin_delta.rs

@@ -0,0 +1,70 @@
+use anyhow::Result;
+use thinp::version::TOOLS_VERSION;
+
+mod common;
+use common::*;
+
+//------------------------------------------
+
+#[test]
+fn accepts_v() -> Result<()> {
+    let stdout = thin_delta!("-V").read()?;
+    assert_eq!(stdout, TOOLS_VERSION);
+    Ok(())
+}
+
+#[test]
+fn accepts_version() -> Result<()> {
+    let stdout = thin_delta!("--version").read()?;
+    assert_eq!(stdout, TOOLS_VERSION);
+    Ok(())
+}
+
+const USAGE: &str = "Usage: thin_delta [options] <device or file>\nOptions:\n  {--thin1, --snap1}\n  {--thin2, --snap2}\n  {-m, --metadata-snap} [block#]\n  {--verbose}\n  {-h|--help}\n  {-V|--version}";
+
+#[test]
+fn accepts_h() -> Result<()> {
+    let stdout = thin_delta!("-h").read()?;
+    assert_eq!(stdout, USAGE);
+    Ok(())
+}
+
+#[test]
+fn accepts_help() -> Result<()> {
+    let stdout = thin_delta!("--help").read()?;
+    assert_eq!(stdout, USAGE);
+    Ok(())
+}
+
+#[test]
+fn rejects_bad_option() -> Result<()> {
+    let stderr = run_fail(thin_delta!("--hedgehogs-only"))?;
+    assert!(stderr.contains("unrecognized option \'--hedgehogs-only\'"));
+    Ok(())
+}
+
+#[test]
+fn snap1_unspecified() -> Result<()> {
+    let mut td = TestDir::new()?;
+    let md = mk_valid_md(&mut td)?;
+    let stderr = run_fail(thin_delta!("--snap2", "45", &md))?;
+    assert!(stderr.contains("--snap1 not specified"));
+    Ok(())
+}
+
+#[test]
+fn snap2_unspecified() -> Result<()> {
+    let mut td = TestDir::new()?;
+    let md = mk_valid_md(&mut td)?;
+    let stderr = run_fail(thin_delta!("--snap1", "45", &md))?;
+    assert!(stderr.contains("--snap2 not specified"));
+    Ok(())
+}
+
+#[test]
+fn dev_unspecified() -> Result<()> {
+    let stderr = run_fail(thin_delta!("--snap1", "45", "--snap2", "46"))?;
+    assert!(stderr.contains("No input device provided"));
+    Ok(())
+}
+