pkgs/profpatsch/nman: ✨ fix dotted attribute path parsing for page names

When using dotted attribute paths like `pkgs.profpatsch.nman`, nman was
incorrectly trying to find a man page named "pkgs.profpatsch.nman" instead
of extracting the actual page name "nman" from the last component.

Changes:
- Add extract_page_name_from_attr() helper that splits on '.' and returns last component
- Update CLI parsing to use helper for auto-detected page names (cases 2 and 3 args)
- Add comprehensive test coverage for the helper function
- Maintain backward compatibility for simple attribute names and explicit page names
- Add description to the man page

Now `nman --local pkgs.profpatsch.nman` correctly builds the full attribute
but searches for the "nman" man page instead of "pkgs.profpatsch.nman".

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <[email protected]>

Author: Profpatsch

pkgs/profpatsch/nman/nman.1

@@ -36,6 +36,11 @@ of
 and searches all its outputs for a man page named
 .Ar ATTR
 which may be in any section.
+For dotted attribute paths like
+.Ql pkgs.profpatsch.nman ,
+only the last component
+.Po Ql nman Pc
+is used as the man page name to search for.
 If multiple matches are found, the one that is alphanumerically
 lower is preferred:
 For example,
@@ -47,6 +52,7 @@ Like above, but
 .Nm
 will only look for the man page in the given section
 .Ar SECTION .
+For dotted attributes, the last component is used as the page name to search for.
 Note that
 .Ar SECTION
 must be a number or
@@ -108,6 +114,9 @@ nman mandoc 7 man
 # open lowdown(1) from local default.nix
 nman --local lowdown
 
+# open nman(1) from dotted attribute path (searches for "nman", not "pkgs.profpatsch.nman")
+nman --local pkgs.profpatsch.nman
+
 # open man page from a custom package set
 nman -l myCustomPackage
 .Ed

pkgs/profpatsch/nman/nman.rs

@@ -26,9 +26,9 @@ fn main() {
         std::env::args().partition(|s| s.starts_with("-"));
 
     let mut cli_res: CliResult = match args.len() {
-        2 => Action(CliAction::Man(&args[1], None, &args[1])),
+        2 => Action(CliAction::Man(&args[1], None, extract_page_name_from_attr(&args[1]))),
         3 => match parse_man_section(&args[2]) {
-            Ok(s) => Action(CliAction::Man(&args[1], Some(s), &args[1])),
+            Ok(s) => Action(CliAction::Man(&args[1], Some(s), extract_page_name_from_attr(&args[1]))),
             Err(_) => Action(CliAction::Man(&args[1], None, &args[2])),
         },
         4 => match parse_man_section(&args[2]) {
@@ -616,6 +616,13 @@ fn match_man_page_file(name: &str, section: &str, page: &str) -> bool {
     }
 }
 
+/// Extract the page name from a dotted attribute path.
+/// For example, "pkgs.profpatsch.nman" becomes "nman".
+/// If there are no dots, returns the original string.
+fn extract_page_name_from_attr(attr: &str) -> &str {
+    attr.split('.').last().unwrap_or(attr)
+}
+
 /// Check if a string describes a man section,
 /// i. e. is a number or "3p" (Perl Developer's
 /// manual). Used to distinguish between man pages
@@ -706,6 +713,24 @@ mod tests {
         assert!(parse_man_section("").is_err());
     }
 
+    #[test]
+    fn test_extract_page_name_from_attr() {
+        // Simple case without dots
+        assert_eq!(extract_page_name_from_attr("nman"), "nman");
+        assert_eq!(extract_page_name_from_attr("hello"), "hello");
+        
+        // Dotted attribute paths
+        assert_eq!(extract_page_name_from_attr("pkgs.profpatsch.nman"), "nman");
+        assert_eq!(extract_page_name_from_attr("a.b.c.d"), "d");
+        assert_eq!(extract_page_name_from_attr("nixpkgs.hello"), "hello");
+        
+        // Edge cases
+        assert_eq!(extract_page_name_from_attr(""), "");
+        assert_eq!(extract_page_name_from_attr("."), "");
+        assert_eq!(extract_page_name_from_attr("package."), "");
+        assert_eq!(extract_page_name_from_attr(".package"), "package");
+    }
+
     #[test]
     fn test_output_preference() {
         // lower =^= preferred