Reimplement --navigate as a feature

1 files changed, 106 insertions, 0 deletions

diff --git a/src/features/navigate.rs b/src/features/navigate.rs
new file mode 100644
index 00000000..612ded6f
--- /dev/null
+++ b/src/features/navigate.rs
@@ -0,0 +1,106 @@
+/// Activate diff navigation: use n to jump forwards and N to jump backwards. To change the
+/// file labels used see --file-modified-label, --file-removed-label, --file-added-label,
+/// --file-renamed-label.
+use crate::features::FeatureValueFunction;
+
+pub fn make_feature() -> Vec<(String, FeatureValueFunction)> {
+    builtin_feature!([
+        (
+            "navigate",
+            bool,
+            None,
+            _opt => true
+        ),
+        (
+            "file-modified-label",
+            String,
+            None,
+            _opt => "Δ"
+        )
+    ])
+}
+
+#[cfg(test)]
+mod tests {
+    use std::fs::{remove_file, File};
+    use std::io::Write;
+    use std::path::Path;
+
+    use itertools;
+
+    use crate::config;
+    use crate::git_config::GitConfig;
+    use crate::style::Style;
+
+    #[test]
+    fn test_navigate() {
+        let git_config_contents = b"
+[delta]
+    features = navigate
+[delta \"navigate\"]
+    file-modified-label = \"modified: \"
+";
+        let git_config_path = "delta__test_file_modified_label.gitconfig";
+
+        assert_eq!(make_config(&[], None, None).file_modified_label, "");
+        assert_eq!(
+            make_config(&["--features", "navigate"], None, None).file_modified_label,
+            "Δ"
+        );
+        assert_eq!(
+            make_config(&[], Some(git_config_contents), Some(git_config_path)).file_modified_label,
+            "modified: "
+        );
+
+        let git_config_contents = b"
+[delta \"my-navigate-feature\"]
+    features = navigate
+    file-modified-label = \"modified: \"
+";
+
+        assert_eq!(
+            make_config(&[], Some(git_config_contents), Some(git_config_path)).file_modified_label,
+            ""
+        );
+        assert_eq!(
+            make_config(
+                &["--features", "my-navigate-feature"],
+                Some(git_config_contents),
+                Some(git_config_path)
+            )
+            .file_modified_label,
+            "modified: "
+        );
+
+        remove_file(git_config_path).unwrap();
+    }
+
+    fn _make_style(s: &str, is_emph: bool) -> Style {
+        Style::from_str(s, None, None, None, true, is_emph)
+    }
+
+    fn make_git_config(contents: &[u8], path: &str) -> GitConfig {
+        let path = Path::new(path);
+        let mut file = File::create(path).unwrap();
+        file.write_all(contents).unwrap();
+        GitConfig::from_path(&path)
+    }
+
+    fn make_config(
+        args: &[&str],
+        git_config_contents: Option<&[u8]>,
+        path: Option<&str>,
+    ) -> config::Config {
+        let args: Vec<&str> = itertools::chain(
+            &["/dev/null", "/dev/null", "--24-bit-color", "always"],
+            args,
+        )
+        .map(|s| *s)
+        .collect();
+        let mut git_config = match (git_config_contents, path) {
+            (Some(contents), Some(path)) => Some(make_git_config(contents, path)),
+            _ => None,
+        };
+        config::Config::from_args(&args, &mut git_config)
+    }
+}