Automatically trim ends of stdin/stdout strings (#874)

crates/nu-command/src/filesystem/open.rs

@@ -124,6 +124,7 @@ impl Command for Open {
                 RawStream::new(
                     Box::new(BufferedReader { input: buf_reader }),
                     ctrlc,
+                    false,
                     call_span,
                 ),
                 call_span,

crates/nu-command/src/network/fetch.rs

@@ -362,6 +362,7 @@ fn response_to_buffer(
                 input: buffered_input,
             }),
             engine_state.ctrlc.clone(),
+            false,
             span,
         ),
         span,

crates/nu-command/src/system/run_external.rs

@@ -243,7 +243,7 @@ impl ExternalCommand {
                 let receiver = ChannelReceiver::new(rx);
 
                 Ok(PipelineData::RawStream(
-                    RawStream::new(Box::new(receiver), output_ctrlc, head),
+                    RawStream::new(Box::new(receiver), output_ctrlc, true, head),
                     head,
                     None,
                 ))

crates/nu-command/src/viewers/table.rs

@@ -72,6 +72,7 @@ impl Command for Table {
                         .into_iter(),
                     ),
                     ctrlc,
+                    false,
                     head,
                 ),
                 head,
@@ -188,6 +189,7 @@ impl Command for Table {
                             stream,
                         }),
                         ctrlc,
+                        false,
                         head,
                     ),
                     head,

crates/nu-engine/src/lib.rs

@@ -9,5 +9,7 @@ pub use call_ext::CallExt;
 pub use column::get_columns;
 pub use documentation::{generate_docs, get_brief_help, get_documentation, get_full_help};
 pub use env::*;
-pub use eval::{eval_block, eval_expression, eval_expression_with_input, eval_operator};
+pub use eval::{
+    eval_block, eval_expression, eval_expression_with_input, eval_operator, eval_subexpression,
+};
 pub use glob_from::glob_from;

crates/nu-protocol/src/pipeline_data.rs

@@ -150,6 +150,8 @@ impl PipelineData {
             PipelineData::RawStream(s, ..) => {
                 let mut items = vec![];
 
+                let trim_end = s.trim_end;
+
                 for val in s {
                     match val {
                         Ok(val) => {
@@ -170,6 +172,11 @@ impl PipelineData {
                         }
                     }
                 }
+
+                if trim_end {
+                    output = output.trim_end().to_string();
+                }
+
                 Ok(output)
             }
         }

crates/nu-protocol/src/value/stream.rs

@@ -12,6 +12,7 @@ pub struct RawStream {
     pub leftover: Vec<u8>,
     pub ctrlc: Option<Arc<AtomicBool>>,
     pub is_binary: bool,
+    pub trim_end: bool,
     pub span: Span,
 }
 
@@ -19,6 +20,7 @@ impl RawStream {
     pub fn new(
         stream: Box<dyn Iterator<Item = Result<Vec<u8>, ShellError>> + Send + 'static>,
         ctrlc: Option<Arc<AtomicBool>>,
+        trim_end: bool,
         span: Span,
     ) -> Self {
         Self {
@@ -26,6 +28,7 @@ impl RawStream {
             leftover: vec![],
             ctrlc,
             is_binary: false,
+            trim_end,
             span,
         }
     }
@@ -43,10 +46,16 @@ impl RawStream {
     pub fn into_string(self) -> Result<String, ShellError> {
         let mut output = String::new();
 
+        let trim_end = self.trim_end;
+
         for item in self {
             output.push_str(&item?.as_string()?);
         }
 
+        if trim_end {
+            output = output.trim_end().to_string();
+        }
+
         Ok(output)
     }
 }

src/main.rs

@@ -123,6 +123,7 @@ fn main() -> Result<()> {
                     RawStream::new(
                         Box::new(BufferedReader::new(buf_reader)),
                         Some(ctrlc),
+                        true,
                         redirect_stdin.span,
                     ),
                     redirect_stdin.span,

src/prompt_update.rs

@@ -1,5 +1,5 @@
 use nu_cli::NushellPrompt;
-use nu_engine::eval_block;
+use nu_engine::eval_subexpression;
 use nu_parser::parse;
 use nu_protocol::{
     engine::{EngineState, Stack, StateWorkingSet},
@@ -59,7 +59,7 @@ fn get_prompt_string(
         .and_then(|v| match v {
             Value::Block { val: block_id, .. } => {
                 let block = engine_state.get_block(block_id);
-                eval_block(
+                eval_subexpression(
                     engine_state,
                     stack,
                     block,
@@ -70,7 +70,7 @@ fn get_prompt_string(
             Value::String { val: source, .. } => {
                 let mut working_set = StateWorkingSet::new(engine_state);
                 let (block, _) = parse(&mut working_set, None, source.as_bytes(), true);
-                eval_block(
+                eval_subexpression(
                     engine_state,
                     stack,
                     &block,