From e1c92e90cafe38d860f8819ed4f74db582f3bb00 Mon Sep 17 00:00:00 2001
From: JT <547158+jntrnr@users.noreply.github.com>
Date: Mon, 27 Dec 2021 10:11:18 +1100
Subject: [PATCH] Add line ending autodetect to 'lines' (#589)

---
 crates/nu-command/src/filters/lines.rs | 51 +++++++++++++++++---------
 src/tests/test_strings.rs              |  5 +++
 2 files changed, 38 insertions(+), 18 deletions(-)

diff --git a/crates/nu-command/src/filters/lines.rs b/crates/nu-command/src/filters/lines.rs
index acf59be63..348402fbb 100644
--- a/crates/nu-command/src/filters/lines.rs
+++ b/crates/nu-command/src/filters/lines.rs
@@ -7,8 +7,6 @@ use nu_protocol::{
 #[derive(Clone)]
 pub struct Lines;
 
-const SPLIT_CHAR: char = '\n';
-
 impl Command for Lines {
     fn name(&self) -> &str {
         "lines"
@@ -39,8 +37,10 @@ impl Command for Lines {
             // the Rc structure to continue using it. If split could take ownership
             // of the split values, then this wouldn't be needed
             PipelineData::Value(Value::String { val, span }, ..) => {
+                let split_char = if val.contains("\r\n") { "\r\n" } else { "\n" };
+
                 let lines = val
-                    .split(SPLIT_CHAR)
+                    .split(split_char)
                     .map(|s| s.to_string())
                     .collect::<Vec<String>>();
 
@@ -55,12 +55,18 @@ impl Command for Lines {
                 Ok(iter.into_pipeline_data(engine_state.ctrlc.clone()))
             }
             PipelineData::ListStream(stream, ..) => {
+                let mut split_char = "\n";
+
                 let iter = stream
                     .into_iter()
                     .filter_map(move |value| {
                         if let Value::String { val, span } = value {
+                            if split_char != "\r\n" && val.contains("\r\n") {
+                                split_char = "\r\n";
+                            }
+
                             let inner = val
-                                .split(SPLIT_CHAR)
+                                .split(split_char)
                                 .filter_map(|s| {
                                     if skip_empty && s.is_empty() {
                                         None
@@ -83,22 +89,29 @@ impl Command for Lines {
                 Ok(iter.into_pipeline_data(engine_state.ctrlc.clone()))
             }
             PipelineData::StringStream(stream, span, ..) => {
+                let mut split_char = "\n";
+
                 let iter = stream
                     .into_iter()
                     .map(move |value| match value {
-                        Ok(value) => value
-                            .split(SPLIT_CHAR)
-                            .filter_map(|s| {
-                                if !s.is_empty() {
-                                    Some(Value::String {
-                                        val: s.into(),
-                                        span,
-                                    })
-                                } else {
-                                    None
-                                }
-                            })
-                            .collect::<Vec<Value>>(),
+                        Ok(value) => {
+                            if split_char != "\r\n" && value.contains("\r\n") {
+                                split_char = "\r\n";
+                            }
+                            value
+                                .split(split_char)
+                                .filter_map(|s| {
+                                    if !s.is_empty() {
+                                        Some(Value::String {
+                                            val: s.into(),
+                                            span,
+                                        })
+                                    } else {
+                                        None
+                                    }
+                                })
+                                .collect::<Vec<Value>>()
+                        }
                         Err(err) => vec![Value::Error { error: err }],
                     })
                     .flatten();
@@ -116,8 +129,10 @@ impl Command for Lines {
                 //know to use a different encoding
                 let s = input.collect_string("", &config)?;
 
+                let split_char = if s.contains("\r\n") { "\r\n" } else { "\n" };
+
                 let lines = s
-                    .split(SPLIT_CHAR)
+                    .split(split_char)
                     .map(|s| s.to_string())
                     .collect::<Vec<String>>();
 
diff --git a/src/tests/test_strings.rs b/src/tests/test_strings.rs
index 905251abb..3e542fd71 100644
--- a/src/tests/test_strings.rs
+++ b/src/tests/test_strings.rs
@@ -84,3 +84,8 @@ fn string_in_valuestream() -> TestResult {
 fn single_tick_interpolation() -> TestResult {
     run_test(r#"$'(3 + 4)'"#, "7")
 }
+
+#[test]
+fn detect_newlines() -> TestResult {
+    run_test("'hello\r\nworld' | lines | get 0 | str length", "5")
+}