Support DELTA_PAGER env var

src/bat/output.rs

@@ -50,15 +50,18 @@ impl OutputType {
     ) -> Result<Self> {
         let mut replace_arguments_to_less = false;
 
-        let pager_from_env = match (env::get_env_var("BAT_PAGER"), env::get_env_var("PAGER")) {
-            (Some(bat_pager), _) => Some(bat_pager),
-            (_, Some(pager)) => {
-                // less needs to be called with the '-R' option in order to properly interpret the
-                // ANSI color sequences printed by bat. If someone has set PAGER="less -F", we
-                // therefore need to overwrite the arguments and add '-R'.
-                //
-                // We only do this for PAGER (as it is not specific to 'bat'), not for BAT_PAGER
-                // or bats '--pager' command line option.
+        let pager_from_env = match (
+            env::get_env_var("DELTA_PAGER"),
+            env::get_env_var("BAT_PAGER"),
+            env::get_env_var("PAGER"),
+        ) {
+            (Some(delta_pager), _, _) => Some(delta_pager),
+            (None, Some(bat_pager), _) => Some(bat_pager),
+            (None, None, Some(pager)) => {
+                // less needs to be called with the '-R' option in order to properly interpret ANSI
+                // color sequences. If someone has set PAGER="less -F", we therefore need to
+                // overwrite the arguments and add '-R'.
+                // We only do this for PAGER, since it is used in other contexts.
                 replace_arguments_to_less = true;
                 Some(pager)
             }

src/cli.rs

@@ -477,8 +477,8 @@ pub struct Opt {
     pub inspect_raw_lines: String,
 
     /// Whether to use a pager when displaying output. Options are: auto, always, and never. The
-    /// default pager is `less`: this can be altered by setting the environment variables BAT_PAGER
-    /// or PAGER (BAT_PAGER has priority).
+    /// default pager is `less`: this can be altered by setting the environment variables
+    /// DELTA_PAGER, BAT_PAGER, or PAGER (and that is their order of priority).
     #[structopt(long = "paging", default_value = "auto")]
     pub paging_mode: String,
 

src/options/theme.rs

@@ -65,7 +65,7 @@ fn is_no_syntax_highlighting_syntax_theme_name(theme_name: &str) -> bool {
 ///
 /// Basically:
 /// 1. The theme is specified by the `--theme` option. If this isn't supplied then it is specified
-///    by the `BAT_PAGER` environment variable.
+///    by the `BAT_THEME` environment variable.
 /// 2. Light vs dark mode is specified by the `--light` or `--dark` options. If these aren't
 ///    supplied then it is inferred from the chosen theme.
 ///