Add flag for specifying color preference

bash_tealdeer

@@ -17,6 +17,10 @@ _tealdeer()
 			COMPREPLY=( $(compgen -W 'linux osx sunos windows' -- "${cur}") )
 			return
 			;;
+		--color)
+			COMPREPLY=( $(compgen -W 'always auto never' -- "${cur}") )
+			return
+			;;
 	esac
 
 	if [[ $cur == -* ]]; then

fish_tealdeer

@@ -15,6 +15,7 @@ complete -c tldr -s m -l markdown    -d 'Display the raw markdown instead of ren
 complete -c tldr -s q -l quiet       -d 'Suppress informational messages.' -f
 complete -c tldr      -l config-path -d 'Show config file path.' -f
 complete -c tldr      -l seed-config -d 'Create a basic config.' -f
+complete -c tldr      -l color       -d 'Controls when to use color.' -xa 'always auto never'
 
 function __tealdeer_entries
     tldr --list | string replace -a -i -r "\,\s" "\n"

src/main.rs

@@ -41,7 +41,7 @@ use crate::config::{get_config_path, make_default_config, Config, MAX_CACHE_AGE}
 use crate::error::TealdeerError::{CacheError, ConfigError, UpdateError};
 use crate::formatter::print_lines;
 use crate::tokenizer::Tokenizer;
-use crate::types::OsType;
+use crate::types::{ColorOptions, OsType};
 
 const NAME: &str = "tealdeer";
 const APP_INFO: AppInfo = AppInfo {
@@ -69,6 +69,7 @@ Options:
     -q --quiet          Suppress informational messages
     --config-path       Show config file path
     --seed-config       Create a basic config
+    --color <when>      Control when to use color [always, auto, never] [default: auto]
 
 Examples:
 
@@ -104,6 +105,7 @@ struct Args {
     flag_config_path: bool,
     flag_seed_config: bool,
     flag_markdown: bool,
+    flag_color: ColorOptions,
 }
 
 /// Print page by path
@@ -294,6 +296,8 @@ fn main() {
         .and_then(|d| d.deserialize())
         .unwrap_or_else(|e| e.exit());
 
+    println!("{:?}", args);
+
     // Show version and exit
     if args.flag_version {
         let os = get_os();
@@ -313,9 +317,15 @@ fn main() {
 
     // Determine the usage of styles
     #[cfg(target_os = "windows")]
-    let enable_styles = ansi_term::enable_ansi_support().is_ok();
+    let ansi_support = ansi_term::enable_ansi_support().is_ok();
     #[cfg(not(target_os = "windows"))]
-    let enable_styles = true;
+    let ansi_support = true;
+
+    let enable_styles = match args.flag_color {
+        ColorOptions::Always => ansi_support,
+        ColorOptions::Auto => ansi_support,
+        ColorOptions::Never => false,
+    };
 
     // Look up config file, if none is found fall back to default config.
     let config = match Config::load(enable_styles) {

src/types.rs

@@ -27,6 +27,14 @@ impl fmt::Display for OsType {
     }
 }
 
+#[derive(Debug, Eq, PartialEq, Copy, Clone, Deserialize)]
+#[serde(rename_all = "lowercase")]
+pub enum ColorOptions {
+    Always,
+    Auto,
+    Never,
+}
+
 #[derive(Debug, Eq, PartialEq)]
 pub enum LineType {
     Empty,

zsh_tealdeer

@@ -25,6 +25,11 @@ _tealdeer() {
 	"($I -q --quiet)"{-q,--quiet}"[Suppress informational messages]"
 	"($I)--config-path[Show config file path]"
 	"($I)--seed-config[Create a basic config]"
+	"($I --color)"{--color}'[Controls when to use color]:when:((
+	    always
+	    auto
+	    never
+        ))'
 	'(- *)'{-h,--help}'[Display help]'
     	'(- *)'{-v,--version}'[Show version information]'
     	'*:file:_files'