feat: add git branch widget

src/git.zig

@@ -1,16 +1,27 @@
 const std = @import("std");
 const tp = @import("thespian");
 const shell = @import("shell");
+const bin_path = @import("bin_path");
 
-const git_binary = "git";
+var git_path: ?struct {
+    path: ?[:0]const u8 = null,
+} = null;
+
+fn get_git() ?[]const u8 {
+    if (git_path) |p| return p.path;
+    const path = bin_path.find_binary_in_path(std.heap.c_allocator, "git") catch null;
+    git_path = .{ .path = path };
+    return path;
+}
 
 pub fn get_current_branch(allocator: std.mem.Allocator) !void {
+    const git_binary = get_git() orelse return error.GitBinaryNotFound;
     const git_current_branch_cmd = tp.message.fmt(.{ git_binary, "rev-parse", "--abbrev-ref", "HEAD" });
     const handlers = struct {
         fn out(_: usize, parent: tp.pid_ref, _: []const u8, output: []const u8) void {
             var it = std.mem.splitScalar(u8, output, '\n');
-            while (it.next()) |line| if (line.len > 0)
-                parent.send(.{ "git", "current_branch", line }) catch {};
+            while (it.next()) |branch| if (branch.len > 0)
+                parent.send(.{ "git", "current_branch", branch }) catch {};
         }
     };
     try shell.execute(allocator, git_current_branch_cmd, .{

src/tui/mainview.zig

@@ -2,7 +2,6 @@ const std = @import("std");
 const tp = @import("thespian");
 const cbor = @import("cbor");
 const tracy = @import("tracy");
-const git = @import("git");
 const ripgrep = @import("ripgrep");
 const root = @import("root");
 const location_history = @import("location_history");
@@ -828,11 +827,6 @@ const cmds = struct {
     }
     pub const find_in_files_query_meta: Meta = .{ .arguments = &.{.string} };
 
-    pub fn git_branch(self: *Self, _: Ctx) Result {
-        try git.get_current_branch(self.allocator);
-    }
-    pub const git_branch_meta: Meta = .{ .description = "Get the current git branch" };
-
     pub fn shell_execute_log(self: *Self, ctx: Ctx) Result {
         if (!try ctx.args.match(.{ tp.string, tp.more }))
             return error.InvalidShellArgument;

src/tui/status/branch.zig

@@ -0,0 +1,68 @@
+const std = @import("std");
+const tp = @import("thespian");
+const cbor = @import("cbor");
+
+const EventHandler = @import("EventHandler");
+const Plane = @import("renderer").Plane;
+const git = @import("git");
+
+const Widget = @import("../Widget.zig");
+const MessageFilter = @import("../MessageFilter.zig");
+const tui = @import("../tui.zig");
+
+const branch_symbol = "󰘬";
+
+allocator: std.mem.Allocator,
+plane: Plane,
+branch: ?[]const u8 = null,
+
+const Self = @This();
+
+pub fn create(allocator: std.mem.Allocator, parent: Plane, _: ?EventHandler, _: ?[]const u8) @import("widget.zig").CreateError!Widget {
+    const self: *Self = try allocator.create(Self);
+    self.* = .{
+        .allocator = allocator,
+        .plane = try Plane.init(&(Widget.Box{}).opts(@typeName(Self)), parent),
+    };
+    try tui.message_filters().add(MessageFilter.bind(self, receive_git));
+    git.get_current_branch(self.allocator) catch {};
+    return Widget.to(self);
+}
+
+pub fn deinit(self: *Self, allocator: std.mem.Allocator) void {
+    if (self.branch) |p| self.allocator.free(p);
+    self.plane.deinit();
+    allocator.destroy(self);
+}
+
+fn receive_git(self: *Self, _: tp.pid_ref, m: tp.message) MessageFilter.Error!bool {
+    var branch: []const u8 = undefined;
+    if (try cbor.match(m.buf, .{ "git", "current_branch", tp.extract(&branch) })) {
+        if (self.branch) |p| self.allocator.free(p);
+        self.branch = try self.allocator.dupe(u8, branch);
+        return true;
+    }
+    return false;
+}
+
+pub fn layout(self: *Self) Widget.Layout {
+    const branch = self.branch orelse return .{ .static = 0 };
+    var buf: [256]u8 = undefined;
+    var fbs = std.io.fixedBufferStream(&buf);
+    const writer = fbs.writer();
+    writer.print("{s} {s}", .{ branch_symbol, branch }) catch {};
+    const len = self.plane.egc_chunk_width(fbs.getWritten(), 0, 1);
+    return .{ .static = len };
+}
+
+pub fn render(self: *Self, theme: *const Widget.Theme) bool {
+    const branch = self.branch orelse return false;
+    self.plane.set_base_style(theme.editor);
+    self.plane.erase();
+    self.plane.home();
+    self.plane.set_style(theme.statusbar);
+    self.plane.fill(" ");
+    self.plane.home();
+    _ = self.plane.print("{s} {s}", .{ branch_symbol, branch }) catch {};
+    return false;
+}

src/tui/status/widget.zig

@@ -19,6 +19,7 @@ const widgets = std.static_string_map.StaticStringMap(CreateFunction).initCompti
     .{ "clock", @import("clock.zig").create },
     .{ "keybind", @import("keybindstate.zig").create },
     .{ "tabs", @import("tabs.zig").create },
+    .{ "branch", @import("branch.zig").create },
 });
 pub const CreateError = error{ OutOfMemory, WidgetInitFailed };
 pub const CreateFunction = *const fn (allocator: std.mem.Allocator, parent: Plane, event_handler: ?EventHandler, arg: ?[]const u8) CreateError!Widget;