From 95f89a093a253c3a5a0d9471c239966a23e3de7e Mon Sep 17 00:00:00 2001
From: Justin Ma <hustcer@outlook.com>
Date: Sun, 2 Mar 2025 01:30:00 +0800
Subject: [PATCH] Add ansi codes to move cursor position (#15221)
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# Description
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Add ansi codes to move cursor position: `ansi cursor_left`, `ansi
cursor_right`, `ansi cursor_up`, `ansi cursor_down`
Why I add these? I'm trying to add a spinner to the message end for a
long running task, just to find that I need to move the cursor left to
make it work as expected: `with-progress 'Waiting for the task to
finish' { sleep 10sec }`
```nu
def with-progress [
  message: string,         # Message to display
  action: closure,         # Action to perform
  --success: string,       # Success message
  --error: string          # Error message
] {
  print -n $'($message)   '
  # ASCII spinner frames
  let frames = ['⠋', '⠙', '⠹', '⠸', '⠼', '⠴', '⠦', '⠧', '⠇', '⠏']

  # Start the spinner in the background
  let spinner_pid = job spawn {
    mut i = 0
    print -n (ansi cursor_off)
    loop {
      print -n (ansi cursor_left)
      print -n ($frames | get $i)
      sleep 100ms
      $i = ($i + 1) mod ($frames | length)
    }
  }

  # Run the action and capture result
  let result = try {
    do $action
    { success: true }
  } catch {
    { success: false }
  }

  # Stop the spinner
  job kill $spinner_pid
  print "\r                                                  \r"

  # Show appropriate message
  if $result.success {
    print ($success | default '✓ Done!')
  } else {
    print ($error | default '✗ Failed!')
    exit 1
  }
}
```

# User-Facing Changes
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helps us keep track of breaking changes. -->

# Tests + Formatting
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---
 crates/nu-command/src/platform/ansi/ansi_.rs       | 8 ++++++++
 crates/nu-command/tests/commands/platform/ansi_.rs | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/crates/nu-command/src/platform/ansi/ansi_.rs b/crates/nu-command/src/platform/ansi/ansi_.rs
index 4e40f7df3f..143bbc9ac1 100644
--- a/crates/nu-command/src/platform/ansi/ansi_.rs
+++ b/crates/nu-command/src/platform/ansi/ansi_.rs
@@ -466,6 +466,14 @@ static CODE_LIST: LazyLock<Vec<AnsiCode>> = LazyLock::new(|| { vec![
 
     // Cursor position in ESC [ <r>;<c>R where r = row and c = column
     AnsiCode{ short_name: None, long_name:"cursor_position", code: "\x1b[6n".to_string()},
+    // Move cursor one character left
+    AnsiCode{ short_name: None, long_name:"cursor_left", code: "\x1b[D".to_string()},
+    // Move cursor one character right
+    AnsiCode{ short_name: None, long_name:"cursor_right", code: "\x1b[C".to_string()},
+    // Move cursor one line up
+    AnsiCode{ short_name: None, long_name:"cursor_up", code: "\x1b[A".to_string()},
+    // Move cursor one line down
+    AnsiCode{ short_name: None, long_name:"cursor_down", code: "\x1b[B".to_string()},
 
     // Report Terminal Identity
     AnsiCode{ short_name: None, long_name:"identity", code: "\x1b[0c".to_string()},
diff --git a/crates/nu-command/tests/commands/platform/ansi_.rs b/crates/nu-command/tests/commands/platform/ansi_.rs
index c7bea5cafb..7ee80ffe9d 100644
--- a/crates/nu-command/tests/commands/platform/ansi_.rs
+++ b/crates/nu-command/tests/commands/platform/ansi_.rs
@@ -11,7 +11,7 @@ fn test_ansi_shows_error_on_escape() {
 fn test_ansi_list_outputs_table() {
     let actual = nu!("ansi --list | length");
 
-    assert_eq!(actual.out, "425");
+    assert_eq!(actual.out, "429");
 }
 
 #[test]