Skeleton for show-themes command line option

3 files changed, 14 insertions, 0 deletions

diff --git a/src/cli.rs b/src/cli.rs
index 41f6eb89..78c3e179 100644
--- a/src/cli.rs
+++ b/src/cli.rs
@@ -270,6 +270,12 @@ pub struct Opt {
     #[structopt(long = "show-syntax-themes")]
     pub show_syntax_themes: bool,
 
+    /// Show all available delta themes, each with an example of highlighted diff output.
+    /// If diff output is supplied on standard input then this will be used for the demo. For
+    /// example: `git show --color=always | delta --show-themes`.
+    #[structopt(long = "show-themes")]
+    pub show_themes: bool,
+
     #[structopt(long = "no-gitconfig")]
     /// Do not take any settings from git config. See GIT CONFIG section.
     pub no_gitconfig: bool,
diff --git a/src/main.rs b/src/main.rs
index 5757fbab..35662b45 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -65,6 +65,9 @@ fn run_app() -> std::io::Result<i32> {
     } else if opt.show_syntax_themes {
         show_syntax_themes()?;
         return Ok(0);
+    } else if opt.show_themes {
+        show_themes()?;
+        return Ok(0);
     }
 
     let _show_config = opt.show_config;
@@ -302,6 +305,10 @@ where
     }
 }
 
+fn show_themes() -> std::io::Result<()> {
+    Ok(())
+}
+
 #[cfg(not(tarpaulin_include))]
 fn show_syntax_themes() -> std::io::Result<()> {
     let mut opt = cli::Opt::from_args();
diff --git a/src/options/set.rs b/src/options/set.rs
index 354eeea6..e5c1edf0 100644
--- a/src/options/set.rs
+++ b/src/options/set.rs
@@ -169,6 +169,7 @@ pub fn set_options(
             plus_empty_line_marker_style,
             plus_non_emph_style,
             raw,
+            show_themes,
             side_by_side,
             tab_width,
             tokenization_regex,