feat(repl): Save and load command history

repl/Cargo.toml

@@ -21,6 +21,7 @@ gluon_vm = { version = "0.6.2", path = "../vm", features = ["serialization"] } #
 gluon_completion = { path = "../completion", version = "0.6.2" } # GLUON
 gluon_format = { version = "0.6.2", path = "../format" } # GLUON
 
+app_dirs = "1.0.0"
 futures = "0.1.11"
 futures-cpupool = "0.1"
 tokio-core = "0.1"

repl/src/main.rs

@@ -1,6 +1,7 @@
 //! REPL for the gluon programming language
 #![doc(html_root_url = "https://docs.rs/gluon_repl/0.4.1")] // # GLUON
 
+extern crate app_dirs;
 #[macro_use]
 extern crate clap;
 #[cfg(feature = "env_logger")]
@@ -37,6 +38,11 @@ use gluon::vm::Error as VMError;
 
 mod repl;
 
+const APP_INFO: app_dirs::AppInfo = app_dirs::AppInfo {
+    name: "gluon-repl",
+    author: "gluon-lang",
+};
+
 fn run_files<'s, I>(vm: &Thread, files: I) -> Result<()>
 where
     I: Iterator<Item = &'s str>,
@@ -168,7 +174,6 @@ fn main() {
     }
 }
 
-
 #[cfg(test)]
 mod tests {
     // If nothing else this suppresses the unused imports warnings when compiling in test mode

repl/src/repl.glu

@@ -167,16 +167,15 @@ let loop repl : Repl -> IO () =
     let run_line line =
         if string.is_empty (string.trim line) then
             wrap Continue
+        else if string.starts_with line ":" then
+            do_command repl.commands line
         else
-            if string.starts_with line ":" then
-                do_command repl.commands line
-            else
-                let action =
-                    do eval_thread = thread.new_thread ()
-                    let eval_action = repl_prim.eval_line line
-                    repl_prim.finish_or_interrupt repl.cpu_pool eval_thread eval_action
-                io.catch action wrap >>= io.println
-                    *> wrap Continue
+            let action =
+                do eval_thread = thread.new_thread ()
+                let eval_action = repl_prim.eval_line line
+                repl_prim.finish_or_interrupt repl.cpu_pool eval_thread eval_action
+            io.catch action wrap >>= io.println
+                *> wrap Continue
 
     do line_result = rustyline.readline repl.editor "> "
     match line_result with
@@ -186,7 +185,9 @@ let loop repl : Repl -> IO () =
         do continue = run_line line
         match continue with
         | Continue -> loop repl
-        | Quit -> wrap ()
+        | Quit ->
+            do _ = rustyline.save_history repl.editor
+            wrap ()
 
 let run x : () -> IO () =
     do _ = io.println "gluon (:h for help, :q to quit)"

repl/src/repl.rs

@@ -4,6 +4,7 @@ extern crate rustyline;
 extern crate gluon_completion as completion;
 
 use std::error::Error as StdError;
+use std::path::PathBuf;
 use std::sync::Mutex;
 
 use futures::{Future, Sink, Stream};
@@ -162,7 +163,6 @@ struct CpuPool(self::futures_cpupool::CpuPool);
 
 impl_userdata!{ CpuPool }
 
-
 #[derive(Serialize, Deserialize)]
 pub enum ReadlineError {
     Eof,
@@ -192,9 +192,22 @@ impl<'vm> Pushable<'vm> for ReadlineError {
     }
 }
 
+fn app_dir_root() -> Result<PathBuf, Box<StdError>> {
+    Ok(::app_dirs::app_root(
+        ::app_dirs::AppDataType::UserData,
+        &::APP_INFO,
+    )?)
+}
 
 fn new_editor(vm: WithVM<()>) -> IO<Editor> {
     let mut editor = rustyline::Editor::new();
+
+    let history_result =
+        app_dir_root().and_then(|path| Ok(editor.load_history(&*path.join("history"))?));
+
+    if let Err(err) = history_result {
+        warn!("Unable to load history: {}", err);
+    }
     editor.set_completer(Some(Completer(vm.vm.root_thread())));
     IO::Value(Editor(Mutex::new(editor)))
 }
@@ -354,7 +367,6 @@ fn finish_or_interrupt(
 
     let (sender, receiver) = mpsc::channel(1);
 
-
     remote.spawn(|handle| {
         ::tokio_signal::ctrl_c(handle)
             .map(|x| {
@@ -390,6 +402,25 @@ fn finish_or_interrupt(
     ))
 }
 
+fn save_history(editor: &Editor) -> IO<()> {
+    let history_result = app_dir_root().and_then(|path| {
+        editor
+            .0
+            .lock()
+            .unwrap()
+            .save_history(&*path.join("history"))
+            .map_err(|err| {
+                let err: Box<StdError> = Box::new(err);
+                err
+            })
+    });
+
+    if let Err(err) = history_result {
+        warn!("Unable to load history: {}", err);
+    }
+    IO::Value(())
+}
+
 fn load_rustyline(vm: &Thread) -> vm::Result<vm::ExternModule> {
     vm.register_type::<Editor>("Editor", &[])?;
     vm.register_type::<CpuPool>("CpuPool", &[])?;
@@ -398,7 +429,8 @@ fn load_rustyline(vm: &Thread) -> vm::Result<vm::ExternModule> {
         vm,
         record!(
             new_editor => primitive!(1 new_editor),
-            readline => primitive!(2 readline)
+            readline => primitive!(2 readline),
+            save_history => primitive!(1 save_history)
         ),
     )
 }