From 88d6926f786874060b378110329181817572c157 Mon Sep 17 00:00:00 2001
From: coolreader18 <33094578+coolreader18@users.noreply.github.com>
Date: Thu, 21 Mar 2019 20:25:16 -0500
Subject: [PATCH 1/3] Make the REPL handle continuation better

---
 src/main.rs | 36 ++++++++++++++++++++++++++++--------
 1 file changed, 28 insertions(+), 8 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 1b92a5ee46..a7dffb02d7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -159,6 +159,14 @@ fn get_history_path() -> PathBuf {
     xdg_dirs.place_cache_file("repl_history.txt").unwrap()
 }
 
+fn get_prompt(vm: &mut VirtualMachine, prompt_name: &str) -> String {
+    vm.sys_module
+        .get_attr(prompt_name)
+        .as_ref()
+        .map(objstr::get_value)
+        .unwrap_or_else(String::new)
+}
+
 fn run_shell(vm: &mut VirtualMachine) -> PyResult {
     println!(
         "Welcome to the magnificent Rust Python {} interpreter",
@@ -176,25 +184,36 @@ fn run_shell(vm: &mut VirtualMachine) -> PyResult {
         println!("No previous history.");
     }
 
-    let ps1 = &objstr::get_value(&vm.sys_module.get_attr("ps1").unwrap());
-    let ps2 = &objstr::get_value(&vm.sys_module.get_attr("ps2").unwrap());
-    let mut prompt = ps1;
+    let mut prompt = get_prompt(vm, "ps1");
+
+    let mut continuing = false;
 
     loop {
-        match repl.readline(prompt) {
+        if !continuing {
+            prompt = get_prompt(vm, "ps1");
+        }
+        match repl.readline(&prompt) {
             Ok(line) => {
                 debug!("You entered {:?}", line);
                 input.push_str(&line);
-                input.push_str("\n");
+                input.push('\n');
                 repl.add_history_entry(line.trim_end());
 
+                if continuing {
+                    if line.is_empty() {
+                        continuing = false;
+                    } else {
+                        continue;
+                    }
+                }
+
                 match shell_exec(vm, &input, vars.clone()) {
                     Err(CompileError::Parse(ParseError::EOF(_))) => {
-                        prompt = ps2;
+                        prompt = get_prompt(vm, "ps2");
+                        continuing = true;
                         continue;
                     }
                     _ => {
-                        prompt = ps1;
                         input = String::new();
                     }
                 }
@@ -202,7 +221,8 @@ fn run_shell(vm: &mut VirtualMachine) -> PyResult {
             Err(ReadlineError::Interrupted) => {
                 // TODO: Raise a real KeyboardInterrupt exception
                 println!("^C");
-                break;
+                continuing = false;
+                continue;
             }
             Err(ReadlineError::Eof) => {
                 break;

From 2c93c79ac8c127b9390520f07095759476b36417 Mon Sep 17 00:00:00 2001
From: coolreader18 <33094578+coolreader18@users.noreply.github.com>
Date: Fri, 22 Mar 2019 01:53:55 -0500
Subject: [PATCH 2/3] Immutable prompt variable

---
 src/main.rs | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index a7dffb02d7..87ed80868e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -184,14 +184,14 @@ fn run_shell(vm: &mut VirtualMachine) -> PyResult {
         println!("No previous history.");
     }
 
-    let mut prompt = get_prompt(vm, "ps1");
-
     let mut continuing = false;
 
     loop {
-        if !continuing {
-            prompt = get_prompt(vm, "ps1");
-        }
+        let prompt = if continuing {
+            get_prompt(vm, "ps2")
+        } else {
+            get_prompt(vm, "ps1")
+        };
         match repl.readline(&prompt) {
             Ok(line) => {
                 debug!("You entered {:?}", line);
@@ -209,7 +209,6 @@ fn run_shell(vm: &mut VirtualMachine) -> PyResult {
 
                 match shell_exec(vm, &input, vars.clone()) {
                     Err(CompileError::Parse(ParseError::EOF(_))) => {
-                        prompt = get_prompt(vm, "ps2");
                         continuing = true;
                         continue;
                     }

From 36ff4e37d360fe8dad35409b25e65aef34fe53d2 Mon Sep 17 00:00:00 2001
From: coolreader18 <33094578+coolreader18@users.noreply.github.com>
Date: Fri, 22 Mar 2019 07:29:14 -0500
Subject: [PATCH 3/3] Use vm.get_attribute

---
 src/main.rs | 14 ++++----------
 1 file changed, 4 insertions(+), 10 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index 87ed80868e..4393946273 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -10,14 +10,8 @@ extern crate rustyline;
 use clap::{App, Arg};
 use rustpython_parser::error::ParseError;
 use rustpython_vm::{
-    compile,
-    error::CompileError,
-    frame::Scope,
-    import,
-    obj::objstr,
-    print_exception,
-    pyobject::{AttributeProtocol, PyResult},
-    util, VirtualMachine,
+    compile, error::CompileError, frame::Scope, import, obj::objstr, print_exception,
+    pyobject::PyResult, util, VirtualMachine,
 };
 use rustyline::{error::ReadlineError, Editor};
 use std::path::{Path, PathBuf};
@@ -160,8 +154,8 @@ fn get_history_path() -> PathBuf {
 }
 
 fn get_prompt(vm: &mut VirtualMachine, prompt_name: &str) -> String {
-    vm.sys_module
-        .get_attr(prompt_name)
+    vm.get_attribute(vm.sys_module.clone(), prompt_name)
+        .ok()
         .as_ref()
         .map(objstr::get_value)
         .unwrap_or_else(String::new)