feat: untracked and modified files are identified by git

Git service offers untracked files and modified ones
staged or not filtering out any other statuses and marking
if new or modified.  This includes renamed files.

src/git.zig

@@ -174,6 +174,105 @@ pub fn status(context_: usize) Error!void {
     }.result, exit_null(tag));
 }
 
+pub fn new_or_modified_files(context_: usize) Error!void {
+    const tag = @src().fn_name;
+    try git_err(context_, .{
+        "--no-optional-locks",
+        "status",
+        "--porcelain=v2",
+        "--null",
+    }, struct {
+        fn result(context: usize, parent: tp.pid_ref, output: []const u8) void {
+            var it_ = std.mem.splitScalar(u8, output, 0);
+            var counter: u8 = 0;
+
+            while (it_.next()) |line| {
+                var it = std.mem.splitScalar(u8, line, ' ');
+                const rec_type = if (it.next()) |type_tag|
+                    std.meta.stringToEnum(StatusRecordType, type_tag) orelse {
+                        if (type_tag.len > 0)
+                            std.log.debug("found {s}, it happens when a file is renamed and not modified. Check `git --no-optional-locks status --porcelain=v2`", .{type_tag});
+                        continue;
+                    }
+                else
+                    return;
+                switch (rec_type) {
+                    .@"1" => { // ordinary file: <XY> <sub> <mH> <mI> <mW> <hH> <hI> <path>
+                        const sub = it.next() orelse return;
+                        const mH = it.next() orelse return;
+                        var vcs_status: u8 = undefined;
+                        if (sub[0] == 'A') {
+                            // New staged file is shown as new
+                            vcs_status = '+';
+                        } else if (sub[0] == 'M' or sub[1] == 'M') {
+                            if (mH[0] == 'S') {
+                                // We do not handle submodules, yet
+                                continue;
+                            }
+                            vcs_status = '~';
+                        } else {
+                            // We will not edit deleted files
+                            continue;
+                        }
+
+                        for (0..5) |_| {
+                            _ = it.next() orelse return;
+                        }
+                        var path: std.ArrayListUnmanaged(u8) = .empty;
+                        defer path.deinit(allocator);
+                        while (it.next()) |path_part| {
+                            if (path.items.len > 0) path.append(allocator, ' ') catch return;
+                            path.appendSlice(allocator, path_part) catch return;
+                        }
+
+                        parent.send(.{ module_name, context, tag, vcs_status, path.items }) catch {};
+                        counter += 1;
+                    },
+                    .@"2" => {
+                        const sub = it.next() orelse return;
+                        if (sub[0] != 'R') {
+                            continue;
+                        }
+                        // An staged file is editable
+                        // renamed: <XY> <sub> <mH> <mI> <mW> <hH> <hI> <rn> <path>
+                        for (0..7) |_| {
+                            _ = it.next() orelse return;
+                        }
+                        var path: std.ArrayListUnmanaged(u8) = .empty;
+                        defer path.deinit(allocator);
+                        while (it.next()) |path_part| {
+                            if (path.items.len > 0) path.append(allocator, ' ') catch return;
+                            path.appendSlice(allocator, path_part) catch return;
+                        }
+                        parent.send(.{ module_name, context, tag, '+', path.items }) catch {};
+                        counter += 1;
+                    },
+                    .@"?" => { // untracked file: <path>
+                        var path: std.ArrayListUnmanaged(u8) = .empty;
+                        defer path.deinit(allocator);
+                        while (it.next()) |path_part| {
+                            if (path.items.len > 0) path.append(allocator, ' ') catch return;
+                            path.appendSlice(allocator, path_part) catch return;
+                        }
+                        parent.send(.{ module_name, context, tag, '+', path.items }) catch {};
+                        counter += 1;
+                    },
+                    else => {
+                        // Omit showing other statuses
+                    },
+                }
+            }
+            std.log.info("git: {} changed files", .{counter});
+        }
+    }.result, struct {
+        fn result(_: usize, _: tp.pid_ref, output: []const u8) void {
+            var it = std.mem.splitScalar(u8, output, '\n');
+            while (it.next()) |line| if (line.len > 0)
+                std.log.err("{s}: {s}", .{ module_name, line });
+        }
+    }.result, exit_null(tag));
+}
+
 fn git_line_output(context_: usize, comptime tag: []const u8, cmd: anytype) Error!void {
     try git_err(context_, cmd, struct {
         fn result(context: usize, parent: tp.pid_ref, output: []const u8) void {