refactor: create new run function in main using anytype

build.zig

@@ -14,6 +14,19 @@ pub fn build(b: *std.Build) void {
 
     b.installArtifact(exe);
 
+    const tests = b.addTest(.{
+        .name = "tpb",
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("src/main.zig"),
+            .target = target,
+            .optimize = optimize,
+        }),
+    });
+
+    const test_step = b.step("test", "Run tests");
+    const run_tests = b.addRunArtifact(tests);
+    test_step.dependOn(&run_tests.step);
+
     const run_step = b.step("run", "Run the app");
 
     const run_cmd = b.addRunArtifact(exe);

src/Clip.zig

@@ -1 +1,30 @@
 pub const OSC52 = @import("Clip/OSC52.zig");
+
+// I am not sure if this is super idiomatic Zig or if this is bad practice, but
+// by ensuring that all Clip backends implement the same methods, we are able
+// to use the `anytype` type and we are able to have an interface that is able
+// to dispatch statically
+
+/// Check if a function with the given name and type exists.
+/// `@compileError` if not
+fn assertFn(comptime T: type, comptime name: []const u8, comptime Sig: type) void {
+    if (!@import("std").meta.hasFn(T, name))
+        @compileError(@typeName(T) ++ " missing fn " ++ name);
+    if (@TypeOf(@field(T, name)) != Sig)
+        @compileError(@typeName(T) ++ "." ++ name ++ " must be " ++ @typeName(Sig));
+}
+
+test {
+    inline for (@typeInfo(@This()).@"struct".decls) |decl| {
+        // Only grab types of structs
+        const T = @field(@This(), decl.name);
+        if (@TypeOf(T) != type) continue;
+        if (@typeInfo(T) != .@"struct") continue;
+
+        // ==============================
+        // === Interface Requirements ===
+        // ==============================
+        assertFn(T, "writeCopyBuffer", fn (*T, []const u8) anyerror!void);
+        assertFn(T, "writePasteboard", fn (*T) anyerror!void);
+    }
+}

src/Clip/OSC52.zig

@@ -13,7 +13,7 @@ base64buffer: std.ArrayList(u8),
 leftover_bytes: [3]u8,
 leftover_count: u8,
 
-const base64encoder = std.base64.Base64Encoder.init(std.base64.standard_alphabet_chars, null);
+const base64encoder = std.base64.Base64Encoder.init(std.base64.standard_alphabet_chars, '=');
 
 pub fn init(alloc: std.mem.Allocator, io: Io, buf_size: usize) !OSC52 {
     return .{
@@ -25,31 +25,34 @@ pub fn init(alloc: std.mem.Allocator, io: Io, buf_size: usize) !OSC52 {
     };
 }
 
-pub fn writeCopyBuffer(self: *OSC52, buf: []u8) !void {
+pub fn free(self: *OSC52) void {
+    self.base64buffer.clearAndFree(self.alloc);
+}
+
+pub fn writeCopyBuffer(self: *OSC52, buf: []const u8) anyerror!void {
     if (buf.len == 0) return;
 
     // Start of buffer after dealing with leftover bytes
     const buf_idx = 3 - self.leftover_count;
 
-    if (buf.len + self.leftover_count < 3) {
-        const len = buf.len + self.leftover_count;
-        @memcpy(self.leftover_bytes[self.leftover_count..len], buf[0..buf.len]);
-        self.leftover_count = @intCast(len);
+    // When we dont fill the leftover buffer, just copy data
+    if (buf_idx > buf.len) {
+        const end = self.leftover_count + buf.len;
+        @memcpy(self.leftover_bytes[self.leftover_count..end], buf[0..buf.len]);
+        self.leftover_count = @intCast(end);
         return;
     }
 
-    if (self.leftover_count != 0) {
-        @memcpy(self.leftover_bytes[self.leftover_count..3], buf[0..buf_idx]);
-        var temp: [5]u8 = undefined;
-        const s = OSC52.base64encoder.encode(&temp, &self.leftover_bytes);
-        try self.base64buffer.appendSlice(self.alloc, s);
-    }
+    @memcpy(self.leftover_bytes[self.leftover_count..3], buf[0..buf_idx]);
+    var temp: [5]u8 = undefined;
+    var s = OSC52.base64encoder.encode(&temp, &self.leftover_bytes);
+    try self.base64buffer.appendSlice(self.alloc, s);
 
     const chunkable_length = buf.len - ((buf.len - buf_idx) % 3);
-    var chunker = std.mem.window(u8, buf[0..chunkable_length], 3, 3);
+    var chunker = std.mem.window(u8, buf[buf_idx..chunkable_length], 3, 3);
     while (chunker.next()) |chunk| {
-        var temp: [5]u8 = undefined;
-        const s = OSC52.base64encoder.encode(&temp, chunk);
+        // var temp: [5]u8 = undefined;
+        s = OSC52.base64encoder.encode(&temp, chunk);
         try self.base64buffer.appendSlice(self.alloc, s);
     }
 
@@ -59,7 +62,14 @@ pub fn writeCopyBuffer(self: *OSC52, buf: []u8) !void {
     }
 }
 
-pub fn writePasteboard(self: *OSC52) !void {
+pub fn encodeRemaining(self: *OSC52) anyerror!void {
+    var temp: [5]u8 = undefined;
+    const s = OSC52.base64encoder.encode(&temp, self.leftover_bytes[0..self.leftover_count]);
+    try self.base64buffer.appendSlice(self.alloc, s);
+}
+
+pub fn writePasteboard(self: *OSC52) anyerror!void {
+    try self.encodeRemaining();
 
     // https://ghostty.org/docs/vt/osc/52
     const osc_header = &[_]u8{
@@ -76,14 +86,51 @@ pub fn writePasteboard(self: *OSC52) !void {
         0x5c, // '\'
     };
 
-    // Write leftover bytes
-    var temp: [5]u8 = undefined;
-    const s = OSC52.base64encoder.encode(&temp, self.leftover_bytes[0..self.leftover_count]);
-    try self.base64buffer.appendSlice(self.alloc, s);
-
     // Write data to stdout
     const stdout = Io.File.stdout();
     try stdout.writeStreamingAll(self.io, osc_header);
     try stdout.writeStreamingAll(self.io, self.base64buffer.items);
     try stdout.writeStreamingAll(self.io, osc_footer);
 }
+
+test "basic base64 encode" {
+    var osc = try OSC52.init(std.testing.allocator, std.testing.io, 1024);
+    defer osc.free();
+    try osc.writeCopyBuffer("part1");
+    try osc.encodeRemaining();
+    try std.testing.expectEqualSlices(u8, "cGFydDE=", osc.base64buffer.items);
+}
+
+test "multi part base64 encode" {
+    var osc = try OSC52.init(std.testing.allocator, std.testing.io, 1024);
+    defer osc.free();
+    try osc.writeCopyBuffer("part1");
+    try osc.writeCopyBuffer("part2");
+    try osc.encodeRemaining();
+    try std.testing.expectEqualSlices(u8, "cGFydDFwYXJ0Mg==", osc.base64buffer.items);
+}
+
+test "tiny buffers base64 encode" {
+    var osc = try OSC52.init(std.testing.allocator, std.testing.io, 1024);
+    defer osc.free();
+    try osc.writeCopyBuffer("part1");
+    try osc.writeCopyBuffer("part2");
+    try osc.writeCopyBuffer("1");
+    try osc.writeCopyBuffer("2");
+    try osc.writeCopyBuffer("3");
+    try osc.writeCopyBuffer("45");
+    try osc.writeCopyBuffer("6");
+    try osc.writeCopyBuffer("78");
+    try osc.writeCopyBuffer("90fin");
+    try osc.encodeRemaining();
+    try std.testing.expectEqualSlices(u8, "cGFydDFwYXJ0MjEyMzQ1Njc4OTBmaW4=", osc.base64buffer.items);
+}
+
+test "big buffers base64 encode" {
+    var osc = try OSC52.init(std.testing.allocator, std.testing.io, 1024);
+    defer osc.free();
+    try osc.writeCopyBuffer("part1part1part1part1part1part1part1part1part1|");
+    try osc.writeCopyBuffer("part2part2part2part2part2part2part2part2part2");
+    try osc.encodeRemaining();
+    try std.testing.expectEqualSlices(u8, "cGFydDFwYXJ0MXBhcnQxcGFydDFwYXJ0MXBhcnQxcGFydDFwYXJ0MXBhcnQxfHBhcnQycGFydDJwYXJ0MnBhcnQycGFydDJwYXJ0MnBhcnQycGFydDJwYXJ0Mg==", osc.base64buffer.items);
+}

src/main.zig

@@ -11,11 +11,16 @@ pub fn main(init: std.process.Init) !void {
         std.process.exit(1);
     }
 
-    std.debug.print("\x1b[0;32mCopying the following to Pasteboard\x1b[0m\n", .{});
-
     // We want to avoid doing as many allocations as possible so having raw
     // pages with it being larger should be totally fine
     var clip = try Clip.OSC52.init(std.heap.page_allocator, init.io, std.heap.pageSize());
+    defer clip.free();
+
+    run(io, clip);
+}
+
+pub fn run(io: *std.Io, clip: anytype) !void {
+    std.debug.print("\x1b[0;32mCopying the following to Pasteboard\x1b[0m\n", .{});
 
     var buf: [4096]u8 = undefined;
     while (true) {
@@ -38,3 +43,7 @@ pub fn main(init: std.process.Init) !void {
 
     std.debug.print("\x1b[0;32mCopied To Pasteboard!\x1b[0m\n", .{});
 }
+
+test {
+    _ = @import("Clip.zig");
+}