example/zig-formatter: show how to use formatters from libghostty (#9407)

.github/workflows/test.yml

@@ -95,7 +95,15 @@ jobs:
       fail-fast: false
       matrix:
         dir:
-          [c-vt, c-vt-key-encode, c-vt-paste, c-vt-sgr, zig-vt, zig-vt-stream]
+          [
+            c-vt,
+            c-vt-key-encode,
+            c-vt-paste,
+            c-vt-sgr,
+            zig-formatter,
+            zig-vt,
+            zig-vt-stream,
+          ]
     name: Example ${{ matrix.dir }}
     runs-on: namespace-profile-ghostty-sm
     needs: test

example/zig-formatter/README.md

@@ -0,0 +1,24 @@
+# Example: stdin to HTML using `vtStream` and `TerminalFormatter`
+
+This example demonstrates how to read VT sequences from stdin, parse them
+using `vtStream`, and output styled HTML using `TerminalFormatter`. The
+purpose of this example is primarily to show how to use formatters with
+terminals.
+
+Requires the Zig version stated in the `build.zig.zon` file.
+
+## Usage
+
+Basic usage:
+
+```shell-session
+echo -e "Hello \033[1;32mGreen\033[0m World" | zig build run
+```
+
+This will output HTML with inline styles and CSS palette variables.
+
+You can also pipe complex terminal output:
+
+```shell-session
+ls --color=always | zig build run > output.html
+```

example/zig-formatter/build.zig

@@ -0,0 +1,39 @@
+const std = @import("std");
+
+pub fn build(b: *std.Build) void {
+    const target = b.standardTargetOptions(.{});
+    const optimize = b.standardOptimizeOption(.{});
+
+    const run_step = b.step("run", "Run the app");
+    const test_step = b.step("test", "Run unit tests");
+
+    const exe_mod = b.createModule(.{
+        .root_source_file = b.path("src/main.zig"),
+        .target = target,
+        .optimize = optimize,
+    });
+
+    if (b.lazyDependency("ghostty", .{})) |dep| {
+        exe_mod.addImport(
+            "ghostty-vt",
+            dep.module("ghostty-vt"),
+        );
+    }
+
+    const exe = b.addExecutable(.{
+        .name = "zig_formatter",
+        .root_module = exe_mod,
+    });
+    b.installArtifact(exe);
+
+    const run_cmd = b.addRunArtifact(exe);
+    run_cmd.step.dependOn(b.getInstallStep());
+    if (b.args) |args| run_cmd.addArgs(args);
+    run_step.dependOn(&run_cmd.step);
+
+    const exe_unit_tests = b.addTest(.{
+        .root_module = exe_mod,
+    });
+    const run_exe_unit_tests = b.addRunArtifact(exe_unit_tests);
+    test_step.dependOn(&run_exe_unit_tests.step);
+}

example/zig-formatter/build.zig.zon

@@ -0,0 +1,13 @@
+.{
+    .name = .zig_formatter,
+    .version = "0.0.0",
+    .fingerprint = 0x578de530797eafe6,
+    .dependencies = .{
+        .ghostty = .{ .path = "../../" },
+    },
+    .paths = .{
+        "build.zig",
+        "build.zig.zon",
+        "src",
+    },
+}

example/zig-formatter/src/main.zig

@@ -0,0 +1,41 @@
+const std = @import("std");
+const ghostty_vt = @import("ghostty-vt");
+
+pub fn main() !void {
+    var gpa: std.heap.DebugAllocator(.{}) = .init;
+    defer _ = gpa.deinit();
+    const alloc = gpa.allocator();
+
+    // Create a terminal
+    var t: ghostty_vt.Terminal = try .init(alloc, .{ .cols = 150, .rows = 80 });
+    defer t.deinit(alloc);
+
+    // Create a read-only VT stream for parsing terminal sequences
+    var stream = t.vtStream();
+    defer stream.deinit();
+
+    // Read from stdin
+    const stdin = std.fs.File.stdin();
+    var buf: [4096]u8 = undefined;
+    while (true) {
+        const n = try stdin.readAll(&buf);
+        if (n == 0) break;
+
+        // Replace \n with \r\n
+        for (buf[0..n]) |byte| {
+            if (byte == '\n') try stream.next('\r');
+            try stream.next(byte);
+        }
+    }
+
+    // Use TerminalFormatter to emit HTML
+    const formatter: ghostty_vt.formatter.TerminalFormatter = .init(&t, .{
+        .emit = .html,
+        .palette = &t.color_palette.colors,
+    });
+
+    // Write to stdout
+    var stdout_writer = std.fs.File.stdout().writer(&buf);
+    const stdout = &stdout_writer.interface;
+    try stdout.print("{f}", .{formatter});
+}