From 94cc80944ea5f11b64c4112fb9b21b0ef55da94d Mon Sep 17 00:00:00 2001
From: Daniel Liu <mr.picklepinosaur@gmail.com>
Date: Tue, 2 May 2023 14:43:25 +0900
Subject: [PATCH] history iterator

---
 shrs_line/src/history.rs | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/shrs_line/src/history.rs b/shrs_line/src/history.rs
index 2981c518..08b7fc09 100644
--- a/shrs_line/src/history.rs
+++ b/shrs_line/src/history.rs
@@ -17,13 +17,23 @@ pub trait History {
     fn add(&mut self, cmd: Self::HistoryItem);
     /// Remove all history entries
     fn clear(&mut self);
-    // fn iter(&self) -> impl Iterator<Item = Self::HistoryItem>;
     /// Query for a history entry
     fn search(&self, query: &str) -> Option<&Self::HistoryItem>;
     /// Get number of history entries
     fn len(&self) -> usize;
     /// Get a history entry by index
     fn get(&self, i: usize) -> Option<&Self::HistoryItem>;
+    fn iter(&self) -> HistoryIter<Self::HistoryItem>;
+}
+
+pub struct HistoryIter<'a, It>(Box<dyn Iterator<Item = &'a It>>);
+
+impl<'a, It> Iterator for HistoryIter<'a, It> {
+    type Item = &'a It;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next()
+    }
 }
 
 /// Default implementation of [History] that saves history in process memory
@@ -48,10 +58,6 @@ impl History for DefaultHistory {
         self.hist.clear();
     }
 
-    // fn iter(&self) -> impl Iterator<Item = Self::HistoryItem> {
-    //     todo!()
-    // }
-
     fn search(&self, _query: &str) -> Option<&Self::HistoryItem> {
         todo!()
     }
@@ -64,6 +70,10 @@ impl History for DefaultHistory {
     fn get(&self, i: usize) -> Option<&Self::HistoryItem> {
         self.hist.get(i)
     }
+
+    fn iter(&self) -> HistoryIter<Self::HistoryItem> {
+        HistoryIter(Box::new(self.hist.iter()))
+    }
 }
 
 /// Store the history persistantly in a file on disk
@@ -124,10 +134,6 @@ impl History for FileBackedHistory {
         self.flush().unwrap();
     }
 
-    // fn iter(&self) -> impl Iterator<Item = Self::HistoryItem> {
-    //     todo!()
-    // }
-
     fn search(&self, _query: &str) -> Option<&Self::HistoryItem> {
         todo!()
     }
@@ -139,6 +145,10 @@ impl History for FileBackedHistory {
     fn get(&self, i: usize) -> Option<&Self::HistoryItem> {
         self.hist.get(i)
     }
+
+    fn iter(&self) -> HistoryIter<Self::HistoryItem> {
+        HistoryIter(Box::new(self.hist.iter()))
+    }
 }
 
 fn parse_history_file(hist_file: PathBuf) -> Result<Vec<String>, FileBackedHistoryError> {