save REPL history to a file

This persists the REPL history across program restarts.

The code should probably be cleaned up a bit more, the error handling in
this one is a bit all over the place. This is because we don't want to
make it a hard error in case the history cannot be saved.

1 files changed, 19 insertions, 0 deletions

diff --git a/src/paths.rs b/src/paths.rs
new file mode 100644
index 0000000..f219dc4
--- /dev/null
+++ b/src/paths.rs
@@ -0,0 +1,19 @@
+//! Module to resolve application-specific paths.
+use super::APP_NAME;
+
+use std::path::PathBuf;
+
+/// Returns the path that should be used for the cache.
+pub fn cache_path() -> PathBuf {
+    let mut cache_path = dirs::cache_dir().unwrap();
+    cache_path.push(APP_NAME);
+    cache_path
+}
+
+/// Returns the path that should be used for the REPL history.
+pub fn history_path() -> Option<PathBuf> {
+    let mut config_path = dirs::config_dir()?;
+    config_path.push(APP_NAME);
+    config_path.push("history");
+    Some(config_path)
+}