feat: create and count test data files

They're empty, for now.

Sponsored-by: author

3 files changed, 36 insertions, 4 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 3673319..e9af5eb 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -589,6 +589,7 @@ dependencies = [
  "subplotlib",
  "tempfile",
  "thiserror",
+ "walkdir",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index 79ea8d2..4bce24c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -14,6 +14,7 @@ serde_yaml = "0.8.21"
 structopt = "0.3.25"
 tempfile = "3.2.0"
 thiserror = "1.0.30"
+walkdir = "2.3.2"
 
 [build-dependencies]
 anyhow = "1.0.51"
diff --git a/src/data.rs b/src/data.rs
index f997885..dbea40f 100644
--- a/src/data.rs
+++ b/src/data.rs
@@ -1,5 +1,8 @@
 use crate::specification::{Create, FileCount};
+use std::fs::File;
 use std::path::{Path, PathBuf};
+use tempfile::{tempdir_in, TempDir};
+use walkdir::WalkDir;
 
 /// Test data management for Obnam benchmarks.
 ///
@@ -8,23 +11,43 @@ use std::path::{Path, PathBuf};
 /// structure.
 #[derive(Debug)]
 pub struct Data {
-    tempdir: PathBuf,
+    live: TempDir,
 }
 
 /// Possible errors from managing data.
 #[derive(Debug, thiserror::Error)]
 pub enum DataError {
+    /// Directory creation failed.
+    #[error("Failed to create directory {0}: {1}")]
+    CreateDirectory(PathBuf, std::io::Error),
+
+    /// File creation failed.
+    #[error("Failed to create file {0}: {1}")]
+    CreateFile(PathBuf, std::io::Error),
+
+    /// File counting failed.
+    #[error("Failed to count files in {0}: {1}")]
+    CountFiles(PathBuf, walkdir::Error),
+
+    /// Failed to create a temporary directory.
+    #[error(transparent)]
+    CreateTemp(#[from] std::io::Error),
 }
 
 impl Data {
     pub(crate) fn new(tempdir: &Path) -> Result<Self, DataError> {
+        let live = tempdir_in(&tempdir)?;
         Ok(Self {
-            tempdir: tempdir.to_path_buf(),
+            live,
         })
     }
 
     pub(crate) fn create(&self, create: &Create) -> Result<(), DataError> {
-        println!("create {:?} in {}", create, self.tempdir.display());
+        println!("create {:?} in {}", create, self.live.path().display());
+        for i in 0..create.files {
+            let filename = self.live.path().join(format!("{}", i));
+            File::create(&filename).map_err(|err| DataError::CreateFile(filename, err))?;
+        }
         Ok(())
     }
 
@@ -39,7 +62,14 @@ impl Data {
     }
 
     pub(crate) fn file_count(&self) -> Result<u64, DataError> {
-        Ok(0)
+        let mut n = 0;
+        for entry in WalkDir::new(&self.live).into_iter() {
+            if let Err(err) = entry {
+                return Err(DataError::CountFiles(self.live.path().to_path_buf(), err));
+            }
+            n += 1;
+        }
+        Ok(n)
     }
 
     pub(crate) fn file_size(&self) -> Result<u64, DataError> {