Navigate from theme to theme with n/N when --show-themes

3 files changed, 52 insertions, 15 deletions

diff --git a/src/config.rs b/src/config.rs
index 23b7b97d..eaa295ea 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -13,6 +13,7 @@ use crate::cli;
 use crate::color;
 use crate::delta::State;
 use crate::env;
+use crate::features::navigate;
 use crate::features::side_by_side;
 use crate::git_config::GitConfigEntry;
 use crate::style::{self, Style};
@@ -58,6 +59,7 @@ pub struct Config {
     pub minus_non_emph_style: Style,
     pub minus_style: Style,
     pub navigate: bool,
+    pub navigate_regexp: Option<String>,
     pub null_style: Style,
     pub null_syntect_style: SyntectStyle,
     pub paging_mode: PagingMode,
@@ -154,6 +156,24 @@ impl From<cli::Opt> for Config {
             _ => *style::GIT_DEFAULT_PLUS_STYLE,
         };
 
+        let file_added_label = opt.file_added_label;
+        let file_copied_label = opt.file_copied_label;
+        let file_modified_label = opt.file_modified_label;
+        let file_removed_label = opt.file_removed_label;
+        let file_renamed_label = opt.file_renamed_label;
+
+        let navigate_regexp = if opt.navigate || opt.show_themes {
+            Some(navigate::make_navigate_regexp(
+                opt.show_themes,
+                &file_modified_label,
+                &file_added_label,
+                &file_removed_label,
+                &file_renamed_label,
+            ))
+        } else {
+            None
+        };
+
         Self {
             available_terminal_width: opt.computed.available_terminal_width,
             background_color_extends_to_terminal_width: opt
@@ -163,11 +183,11 @@ impl From<cli::Opt> for Config {
             color_only: opt.color_only,
             decorations_width: opt.computed.decorations_width,
             error_exit_code: 2, // Use 2 for error because diff uses 0 and 1 for non-error.
-            file_added_label: opt.file_added_label,
-            file_copied_label: opt.file_copied_label,
-            file_modified_label: opt.file_modified_label,
-            file_removed_label: opt.file_removed_label,
-            file_renamed_label: opt.file_renamed_label,
+            file_added_label,
+            file_copied_label,
+            file_modified_label,
+            file_removed_label,
+            file_renamed_label,
             file_style,
             git_config_entries: opt.git_config_entries,
             hunk_header_file_style,
@@ -203,6 +223,7 @@ impl From<cli::Opt> for Config {
             minus_non_emph_style,
             minus_style,
             navigate: opt.navigate,
+            navigate_regexp,
             null_style: Style::new(),
             null_syntect_style: SyntectStyle::default(),
             paging_mode: opt.computed.paging_mode,
diff --git a/src/features/navigate.rs b/src/features/navigate.rs
index a38815a6..0020d54b 100644
--- a/src/features/navigate.rs
+++ b/src/features/navigate.rs
@@ -23,14 +23,22 @@ pub fn make_feature() -> Vec<(String, OptionValueFunction)> {
     ])
 }
 
-fn make_navigate_regexp(config: &Config) -> String {
-    format!(
-        "^(commit|{}|{}|{}|{})",
-        config.file_modified_label,
-        config.file_added_label,
-        config.file_removed_label,
-        config.file_renamed_label
-    )
+// Construct the regexp used by less for paging, if --show-themes or --navigate is enabled.
+pub fn make_navigate_regexp(
+    show_themes: bool,
+    file_modified_label: &str,
+    file_added_label: &str,
+    file_removed_label: &str,
+    file_renamed_label: &str,
+) -> String {
+    if show_themes {
+        "^Theme:".to_string()
+    } else {
+        format!(
+            "^(commit|{}|{}|{}|{})",
+            file_modified_label, file_added_label, file_removed_label, file_renamed_label,
+        )
+    }
 }
 
 // Create a less history file to be used by delta's child less process. This file is initialized
@@ -57,7 +65,7 @@ pub fn copy_less_hist_file_and_append_navigate_regexp(config: &Config) -> std::i
         std::fs::File::create(&delta_less_hist_file)?,
         "{}\"{}",
         contents,
-        make_navigate_regexp(config)
+        config.navigate_regexp.as_ref().unwrap(),
     )?;
     Ok(delta_less_hist_file)
 }
diff --git a/src/main.rs b/src/main.rs
index d48a2961..35edb03c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -258,6 +258,7 @@ fn show_config(config: &config::Config, writer: &mut dyn Write) -> std::io::Resu
         "    max-line-distance             = {max_line_distance}
     max-line-length               = {max_line_length}
     navigate                      = {navigate}
+    navigate-regexp               = {navigate_regexp}
     paging                        = {paging_mode}
     side-by-side                  = {side_by_side}
     syntax-theme                  = {syntax_theme}
@@ -267,6 +268,10 @@ fn show_config(config: &config::Config, writer: &mut dyn Write) -> std::io::Resu
         max_line_distance = config.max_line_distance,
         max_line_length = config.max_line_length,
         navigate = config.navigate,
+        navigate_regexp = match &config.navigate_regexp {
+            None => "".to_string(),
+            Some(s) => s.to_string(),
+        },
         paging_mode = match config.paging_mode {
             PagingMode::Always => "always",
             PagingMode::Never => "never",
@@ -328,7 +333,10 @@ fn show_themes() -> std::io::Result<()> {
     };
 
     let mut git_config = git_config::GitConfig::try_create();
-    let opt = cli::Opt::from_iter_and_git_config(&["", "", "--navigate"], &mut git_config);
+    let opt = cli::Opt::from_iter_and_git_config(
+        &["", "", "--navigate", "--show-themes"],
+        &mut git_config,
+    );
 
     let mut output_type =
         OutputType::from_mode(PagingMode::Always, None, &config::Config::from(opt)).unwrap();