From 4f05e9f4a6eb0a7b494926213c9ae1e42b9c6b8d Mon Sep 17 00:00:00 2001
From: Darren Schroeder <343840+fdncred@users.noreply.github.com>
Date: Fri, 18 Mar 2022 06:27:33 -0500
Subject: [PATCH] add a display of what the colors look like in `ansi --list`
 (#4866)

* add a display of what the colors look like in `ansi --list`

* change 'color' to 'preview' - add the ability to turn it off via config with use_ansi_coloring
---
 crates/nu-command/src/platform/ansi/ansi_.rs | 30 +++++++++++++++++---
 1 file changed, 26 insertions(+), 4 deletions(-)

diff --git a/crates/nu-command/src/platform/ansi/ansi_.rs b/crates/nu-command/src/platform/ansi/ansi_.rs
index 50340dc0c8..5f4f17066e 100644
--- a/crates/nu-command/src/platform/ansi/ansi_.rs
+++ b/crates/nu-command/src/platform/ansi/ansi_.rs
@@ -309,9 +309,10 @@ Format: #
         let list: bool = call.has_flag("list");
         let escape: bool = call.has_flag("escape");
         let osc: bool = call.has_flag("osc");
+        let use_ansi_coloring = stack.get_config()?.use_ansi_coloring;
 
         if list {
-            return generate_ansi_code_list(engine_state, call.head);
+            return generate_ansi_code_list(engine_state, call.head, use_ansi_coloring);
         }
 
         // The code can now be one of the ansi abbreviations like green_bold
@@ -416,16 +417,37 @@ pub fn str_to_ansi(s: &str) -> Option<String> {
 fn generate_ansi_code_list(
     engine_state: &nu_protocol::engine::EngineState,
     call_span: Span,
+    use_ansi_coloring: bool,
 ) -> Result<nu_protocol::PipelineData, ShellError> {
     return Ok(CODE_LIST
         .iter()
-        .map(move |ansi_code| {
-            let cols = vec!["name".into(), "short name".into(), "code".into()];
+        .enumerate()
+        .map(move |(i, ansi_code)| {
+            let cols = if use_ansi_coloring {
+                vec![
+                    "name".into(),
+                    "preview".into(),
+                    "short name".into(),
+                    "code".into(),
+                ]
+            } else {
+                vec!["name".into(), "short name".into(), "code".into()]
+            };
             let name: Value = Value::string(String::from(ansi_code.long_name), call_span);
             let short_name = Value::string(ansi_code.short_name.unwrap_or(""), call_span);
+            // The first 96 items in the ansi array are colors
+            let preview = if i < 96 {
+                Value::string(format!("{}NUSHELL\u{1b}[0m", &ansi_code.code), call_span)
+            } else {
+                Value::string("\u{1b}[0m", call_span)
+            };
             let code_string = String::from(&ansi_code.code.replace('\u{1b}', ""));
             let code = Value::string(code_string, call_span);
-            let vals = vec![name, short_name, code];
+            let vals = if use_ansi_coloring {
+                vec![name, preview, short_name, code]
+            } else {
+                vec![name, short_name, code]
+            };
             Value::Record {
                 cols,
                 vals,