Upgrade to Zig 0.16.0; Fix tree-sitter panic issues

Update all APIs and dependencies for Zig v0.16.0

Update tree-sitter to resolve panic issues: Disable address sanitizer
for non-debug builds, and properly handle errors with `ts_stack_merge`
to prevent runtime panics.

perf: use smp_allocator instead of init.gpa

When the binary links libc (due to tree-sitter), init.gpa resolves to
std.heap.c_allocator rather than smp_allocator. The c_allocator is
significantly slower for the many small, short-lived allocations made
during markdown parsing, causing ~10-20% more CPU cycles. Explicitly
using smp_allocator restores performance parity with the 0.15.x build.

Also clean up the file-reading path: replace the Writer.Allocating +
empty-buffer reader with a proper 4096-byte buffer + allocRemaining,
which avoids the unbuffered zero-length read path.

perf: cache compiled TreeSitter queries per language

ts_query_new dominates render time (~97% of CPU). Previously it was
called on every code block, even for the same language. Add a
compiled_queries map to ts_queries that lazily compiles and caches
each language's query on first use; subsequent renders retrieve the
cached *Query in O(1).

syntax.getHighlights() now calls ts_queries.getCompiledQuery() directly,
eliminating the per-call Query.create()/destroy() pair. For documents
with repeated same-language blocks this makes dev/zig-16 ~3% faster
than main; for unique-language documents it avoids the overhead on any
second pass through the same file.

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

Author: JacobCrabill

.gitignore

@@ -5,6 +5,7 @@
 *.a
 zig-out/
 .zig-cache/
+zig-pkg/
 .ccls-cache/
 docs/
 .worktrees/

README.md

@@ -5,7 +5,7 @@
 ![CI Status](https://github.com/JacobCrabill/zigdown/actions/workflows/main.yml/badge.svg)
 
 > [!TIP]
-> Zig 0.15.x Required
+> Zig 0.16.x Required
 
 - [Tools & Features](#tools-&-features)
   - [Command-Line Tools](#command-line-tools)
@@ -120,7 +120,7 @@ subset of all Markdown syntax, and ignoring anything I personally find useless o
 ## Usage
 
 The current version of Zig this code compiles with is
-[0.15.2](https://ziglang.org/download/0.15.2/zig-x86_64-linux-0.15.2.tar.xz). I highly recommend
+[0.16.0](https://ziglang.org/download/0.16.0/zig-x86_64-linux-0.16.0.tar.xz). I highly recommend
 using the [Zig version manager](https://github.com/tristanisham/zvm) to install and manage various
 Zig versions.
 

build.zig

@@ -3,7 +3,6 @@ const builtin = @import("builtin");
 const Build = std.Build;
 const Allocator = std.mem.Allocator;
 
-const ArrayList = std.array_list.Managed;
 const Target = std.Build.ResolvedTarget;
 const OptimizeMode = std.builtin.OptimizeMode;
 const Options = std.Build.Step.Options;
@@ -37,6 +36,7 @@ pub fn build(b: *std.Build) !void {
     const optimize: OptimizeMode = b.standardOptimizeOption(.{});
 
     const wasm_optimize = b.option(OptimizeMode, "wasm-optimize", "Optimization mode for WASM targets") orelse .ReleaseSmall;
+    const no_wasm = b.option(bool, "no-wasm", "Skip building the WASM target") orelse true;
 
     const build_lua = b.option(bool, "lua", "[WIP] Build Zigdown as a Lua module") orelse false;
     const build_test_exes = b.option(bool, "build-test-exes", "Build the custom test executables") orelse false;
@@ -62,10 +62,10 @@ pub fn build(b: *std.Build) !void {
     options.addOption(bool, "extra_tests", do_extra_tests);
 
     // Split the comma-separated list of builtin languages to a list of languages for our config struct
-    var ts_language_list = ArrayList([]const u8).init(b.allocator);
+    var ts_language_list: std.ArrayList([]const u8) = .empty;
     var iter = std.mem.tokenizeScalar(u8, ts_parser_list, ',');
     while (iter.next()) |name| {
-        try ts_language_list.append(name);
+        try ts_language_list.append(b.allocator, name);
     }
     options.addOption([]const []const u8, builtin_ts_option, ts_language_list.items);
 
@@ -80,13 +80,13 @@ pub fn build(b: *std.Build) !void {
     mod.addOptions("config", options);
 
     // Get all of our dependencies, both from build.zig.zon and our TreeSitter module
-    var deps: ArrayList(Dependency) = try getDependencies(b, target, optimize, ts_language_list.items);
+    var deps: std.ArrayList(Dependency) = try getDependencies(b, target, optimize, ts_language_list.items);
 
     // Add all dependencies to our "root" Zigdown module, then add that to the dependencies list
     for (deps.items) |dep| {
         mod.addImport(dep.name, dep.module);
     }
-    try deps.append(mod_dep);
+    try deps.append(b.allocator, mod_dep);
 
     const exe_opts = BuildOpts{
         .target = target,
@@ -159,7 +159,7 @@ pub fn build(b: *std.Build) !void {
         lua_mod.root_module.addImport(ziglua_dep.name, ziglua_dep.module);
 
         const luajit_lib = ziglua.artifact("lua");
-        lua_mod.linkLibrary(luajit_lib);
+        lua_mod.root_module.linkLibrary(luajit_lib);
 
         b.installArtifact(lua_mod);
 
@@ -208,14 +208,17 @@ pub fn build(b: *std.Build) !void {
     // TODO: Still requires some implementation of much of libC to link.
     // See: https://github.com/floooh/pacman.zig/blob/main/build.zig for an
     // example of using Emscripten as the linker
+    // NOTE: Currently broken due to std.Io.Threaded stdlib issue on this host.
+    //       Use `-Dno-wasm` to skip.
     ////////////////////////////////////////////////////////////////////////////
+    if (!no_wasm) {
     const wasm_target = b.resolveTargetQuery(.{
         .cpu_arch = .wasm32,
         .os_tag = .freestanding,
         .abi = .musl,
     });
 
-    var wasm_deps: ArrayList(Dependency) = try getDependencies(b, wasm_target, wasm_optimize, ts_language_list.items);
+    var wasm_deps: std.ArrayList(Dependency) = try getDependencies(b, wasm_target, wasm_optimize, ts_language_list.items);
 
     const wasm_mod = b.addModule("zigdown_wasm", .{
         .root_source_file = b.path("src/lib/zigdown.zig"),
@@ -229,7 +232,7 @@ pub fn build(b: *std.Build) !void {
     for (wasm_deps.items) |dep| {
         wasm_mod.addImport(dep.name, dep.module);
     }
-    try wasm_deps.append(wasm_mod_dep);
+    try wasm_deps.append(b.allocator, wasm_mod_dep);
 
     const wasm = b.addExecutable(.{
         .name = "zigdown-wasm",
@@ -269,6 +272,7 @@ pub fn build(b: *std.Build) !void {
         b.installArtifact(wasm);
         b.getInstallStep().dependOn(wasm_step);
     }
+    } // end if (!no_wasm)
 
     ////////////////////////////////////////////////////////////////////////////
     // Add unit tests
@@ -386,8 +390,8 @@ fn isWasm(target: std.Build.ResolvedTarget) bool {
     return false;
 }
 
-fn getDependencies(b: *std.Build, target: Target, optimize: OptimizeMode, ts_language_list: []const []const u8) !ArrayList(Dependency) {
-    var dependencies = ArrayList(Dependency).init(b.allocator);
+fn getDependencies(b: *std.Build, target: Target, optimize: OptimizeMode, ts_language_list: []const []const u8) !std.ArrayList(Dependency) {
+    var dependencies: std.ArrayList(Dependency) = .empty;
 
     // Module for baked-in data and files
     const asset_mod = b.addModule("assets", .{
@@ -433,7 +437,7 @@ fn getDependencies(b: *std.Build, target: Target, optimize: OptimizeMode, ts_lan
         }
     }
 
-    try dependencies.append(asset_dep);
+    try dependencies.append(b.allocator, asset_dep);
 
     if (!isWasm(target)) {
         ///////////////////////////////////////////////////////////////////////////
@@ -442,30 +446,30 @@ fn getDependencies(b: *std.Build, target: Target, optimize: OptimizeMode, ts_lan
         // STB-Image
         const stbi = b.dependency("stbi", .{ .optimize = optimize, .target = target });
         const stbi_dep = Dependency{ .name = "stb_image", .module = stbi.module("stb_image") };
-        try dependencies.append(stbi_dep);
+        try dependencies.append(b.allocator, stbi_dep);
 
         const target_os: std.Target.Os.Tag = target.query.os_tag orelse builtin.os.tag;
         if (target_os != .windows) {
             // PlutoSVG
             const plutosvg = b.dependency("plutosvg", .{ .optimize = optimize, .target = target });
             const plutosvg_dep = Dependency{ .name = "plutosvg", .module = plutosvg.module("plutosvg") };
-            try dependencies.append(plutosvg_dep);
+            try dependencies.append(b.allocator, plutosvg_dep);
         }
 
         // Flags
         const flags = b.dependency("flags", .{ .optimize = optimize, .target = target });
         const flags_dep = Dependency{ .name = "flags", .module = flags.module("flags") };
-        try dependencies.append(flags_dep);
+        try dependencies.append(b.allocator, flags_dep);
 
         // Treez (TreeSitter wrapper library)
         const treez = b.dependency("treez", .{ .optimize = optimize, .target = target });
         const treez_dep = Dependency{ .name = "treez", .module = treez.module("treez") };
-        try dependencies.append(treez_dep);
+        try dependencies.append(b.allocator, treez_dep);
         asset_mod.addImport(treez_dep.name, treez_dep.module);
 
         const known_folders = b.dependency("known_folders", .{ .optimize = optimize, .target = target });
         const known_folders_dep = Dependency{ .name = "known-folders", .module = known_folders.module("known-folders") };
-        try dependencies.append(known_folders_dep);
+        try dependencies.append(b.allocator, known_folders_dep);
     }
 
     return dependencies;

build.zig.zon

@@ -1,8 +1,8 @@
 .{
     .name = .zigdown,
     .fingerprint = 0xec26eaf34f894e33,
-    .version = "1.2.2",
-    .minimum_zig_version = "0.15.1",
+    .version = "1.3.0",
+    .minimum_zig_version = "0.16.0",
     .paths = .{
         "lua",
         "plugin",
@@ -17,24 +17,26 @@
             .hash = "zig_stb_image-2.28.0-2-9dD1dfoYBQCzF7IA9_-tSbsF1PgN7HGfzDzGVRG2BoUY",
         },
         .plutosvg = .{
-            .url = "https://github.com/JacobCrabill/zig-plutosvg/archive/b2dcac090852c9b26f16798dbbb35c3da1f65773.tar.gz",
-            .hash = "plutosvg-0.0.6-1-LyMxgYguAABq-4Xf7BWKdsl27x3fq5EUgsYS1LmGq9bW",
+            .url = "https://github.com/JacobCrabill/zig-plutosvg/archive/7704671d5130040fb8a25e45c8112809aa89ae6c.tar.gz",
+            .hash = "plutosvg-0.0.6-2-LyMxgdAuAACyA7po0YLhr75Net3boHUgEf3SP2k7DY-1",
         },
         .flags = .{
-            .url = "https://github.com/JacobCrabill/zig-flags/archive/8f65f0d5bf0d92b950ddf16afb34533491831c7d.tar.gz",
-            .hash = "flags-0.11.0-a_9h3gR2AACtwEzEcKhIsYPEgNPbBeGYKhbYL4lsmJ1N",
+            .url = "https://github.com/JacobCrabill/zig-flags/archive/de90d081cd4ef7907fbdd8e1e3853fcee9bcf1b9.tar.gz",
+            .hash = "flags-0.12.0-a_9h3p94AACZ_64EtswSKUGy_mvh8IVL8CIiu0SVebvS",
         },
         .treez = .{
-            .url = "https://github.com/JacobCrabill/treez/archive/980316cb4fd0da6075a6a8f86bd1a3927bf68ad3.tar.gz",
-            .hash = "treez-0.2.0-4JX9hV6mAAA-T-vae75m4eZSgIxKsv6uUae21-Dzhh8l",
+            .url = "https://github.com/JacobCrabill/treez/archive/2d1f27c92a2d4a2179740a8ba4bd866b328dd24f.tar.gz",
+            .hash = "treez-0.2.0-4JX9hYSkAABbotzNQsOTNzU8wcDglGCo9Ffik-qi1o_a",
         },
         .known_folders = .{
-            .url = "git+https://github.com/ziglibs/known-folders.git#ab5cf5feb936fa3b72c95d3ad0c0c67791937ba1",
-            .hash = "known_folders-0.0.0-Fy-PJtTTAADUOhGKM0sxzG4eMkNQxRvx9e5dfHVyaeA3",
+            .url = "https://github.com/ziglibs/known-folders/archive/5865fd0f1bc5241de8355fcf2066692bf1b0ea02.tar.gz",
+            .hash = "known_folders-0.0.0-Fy-PJpLKAAAmMEnwre7fFcfsxBGULd24N8Bp2pWEu3sf",
         },
         .ziglua = .{
-            .url = "https://github.com/JacobCrabill/ziglua/archive/011758bab2c2b5a4b6e678e33a8dbb24570d4394.tar.gz",
-            .hash = "zlua-0.2.0-hGRpC2sYBQCawPfqP3rxM95KUN3IYdRNKTAeSussl7kM",
+            // .url = "https://github.com/JacobCrabill/ziglua/archive/011758bab2c2b5a4b6e678e33a8dbb24570d4394.tar.gz",
+            // .hash = "zlua-0.2.0-hGRpC2sYBQCawPfqP3rxM95KUN3IYdRNKTAeSussl7kM",
+            .url = "https://github.com/natecraddock/ziglua/archive/22cad3abc50bca7c73145e07ed2835926e2dda44.tar.gz",
+            .hash = "zlua-0.1.0-hGRpC5dqBQCm1fzCu23-RM5xE9_6JSnUitX9HFi9jSYA",
             .lazy = true,
         },
         // Needed in order for ziglua to build luajit.
@@ -47,44 +49,44 @@
 
         // Individual TreeSitter language parsers
         .tree_sitter_bash = .{
-            .url = "https://github.com/tree-sitter/tree-sitter-bash/archive/49c31006d8307dcb12bc5770f35b6d5b9e2be68e.tar.gz",
-            .hash = "N-V-__8AAG_cogDl9X3jxLCGR6dsBzkjlX8TYhtdCCvonOUr",
+            .url = "https://github.com/tree-sitter/tree-sitter-bash/archive/a06c2e4415e9bc0346c6b86d401879ffb44058f7.tar.gz",
+            .hash = "N-V-__8AANjenwCy_cXlIbU8nqBzGxMlEHVokLZJYrmIXtoz",
         },
         .tree_sitter_c = .{
-            .url = "https://github.com/tree-sitter/tree-sitter-c/archive/e8841a6a9431b7365ac9055688429e1deb8db90f.tar.gz",
-            .hash = "N-V-__8AALWcSAD2F6Vd1LSqa0js-e6kawfanpXMUnMhQeq6",
+            .url = "https://github.com/tree-sitter/tree-sitter-c/archive/b780e47fc780ddc8da13afa35a3f4ed5c157823d.tar.gz",
+            .hash = "tree_sitter_c-0.24.2-y5boS-ptQADHoCoVfjGT_nFtFQ5LbomIkW0fxG3_cmdB",
         },
         .tree_sitter_cmake = .{
             .url = "https://github.com/uyha/tree-sitter-cmake/archive/fe48221d4d9842d916d66b5e71ab3c6307ec28b3.tar.gz",
             .hash = "N-V-__8AACLOCQCV8GF5uI_qg4S3tygmCZMpxB9qk4L2evjb",
         },
         .tree_sitter_cpp = .{
-            .url = "https://github.com/tree-sitter/tree-sitter-cpp/archive/f41b4f66a42100be405f96bdc4ebc4a61095d3e8.tar.gz",
-            .hash = "N-V-__8AABV0FwF4Ttn0MFCCLOxdUUKUC07SL-wqYa-2ySus",
+            .url = "https://github.com/tree-sitter/tree-sitter-cpp/archive/8b5b49eb196bec7040441bee33b2c9a4838d6967.tar.gz",
+            .hash = "N-V-__8AAMePmwGeojPhBaBC10aGwaQIOU4vg1H17IWakWs-",
         },
         .tree_sitter_json = .{
             .url = "https://github.com/tree-sitter/tree-sitter-json/archive/4d770d31f732d50d3ec373865822fbe659e47c75.tar.gz",
             .hash = "N-V-__8AACVXAgCEl--zqcqoXlvXpEMk5BTS748bsLVslERc",
         },
         .tree_sitter_lua = .{
-            .url = "https://github.com/tree-sitter-grammars/tree-sitter-lua/archive/7040a79f95b0bf7517a9809a8d0ecd41197027ac.tar.gz",
-            .hash = "N-V-__8AAExZCQBbT7NCZKdW4KxnVtSRvSVqTtJt0FEqfSa9",
+            .url = "https://github.com/tree-sitter-grammars/tree-sitter-lua/archive/10fe0054734eec83049514ea2e718b2a56acd0c9.tar.gz",
+            .hash = "N-V-__8AAE5ZCQA-BW5BOioWVkGcPTjhC5x1Qv07BH3Xt3dR",
         },
         .tree_sitter_make = .{
-            .url = "https://github.com/tree-sitter-grammars/tree-sitter-make/archive/5e9e8f8ff3387b0edcaa90f46ddf3629f4cfeb1d.tar.gz",
-            .hash = "N-V-__8AAD6dEwA9hwePYcn8FdDAJEeYqCBBlYI2Oey6O5g2",
+            .url = "https://github.com/tree-sitter-grammars/tree-sitter-make/archive/70613f3d812cbabbd7f38d104d60a409c4008b43.tar.gz",
+            .hash = "N-V-__8AAMVsEgC0rug9JAAca82MW3tyFJrFdRA3ou6VEipn",
         },
         .tree_sitter_python = .{
-            .url = "https://github.com/tree-sitter/tree-sitter-python/archive/de0c01e7102e755f6c2e1b3055ae6ca85f261a10.tar.gz",
-            .hash = "N-V-__8AANVLPgC-yBA9l867GoeMn95l0Y_Q9CAzcizA7qlT",
+            .url = "https://github.com/tree-sitter/tree-sitter-python/archive/26855eabccb19c6abf499fbc5b8dc7cc9ab8bc64.tar.gz",
+            .hash = "N-V-__8AAOiqPgC9tH5tYSAYNsMWLoPiSxcmkHvIhMnezomx",
         },
         .tree_sitter_rust = .{
-            .url = "https://github.com/tree-sitter/tree-sitter-rust/archive/c447dcce961ac438aaeaf117347749fe7d1e8365.tar.gz",
-            .hash = "N-V-__8AAJ3uaABprqh1hqE6xstGrAJWc4xL3u1HfJ6Plj6E",
+            .url = "https://github.com/tree-sitter/tree-sitter-rust/archive/77a3747266f4d621d0757825e6b11edcbf991ca5.tar.gz",
+            .hash = "N-V-__8AAHJYbgAipcanYj2A6rnj9wtGzjGzANkrOsqiFAxm",
         },
         .tree_sitter_yaml = .{
-            .url = "https://github.com/tree-sitter-grammars/tree-sitter-yaml/archive/1805917414a9a8ba2473717fd69447277a175fae.tar.gz",
-            .hash = "N-V-__8AABBcGwBNXXnYqPiNmGDO5T2k7__Tglt1pwNFI_YN",
+            .url = "https://github.com/tree-sitter-grammars/tree-sitter-yaml/archive/a1c4812a73ec5e089de8e441fdea3a921e8d5079.tar.gz",
+            .hash = "N-V-__8AAEkcHQB61IN4Zp5o83gmDa69AUnJUBSFIVM9lGg-",
         },
         .tree_sitter_zig = .{
             .url = "https://github.com/tree-sitter-grammars/tree-sitter-zig/archive/b670c8df85a1568f498aa5c8cae42f51a90473c0.tar.gz",

src/app/lua_api.zig

@@ -48,6 +48,8 @@ export fn render_markdown(lua: ?*LuaState) callconv(.c) c_int {
     const input_a: [*c]const u8 = c.lua_tolstring(lua, 1, &len);
     const input: []const u8 = input_a[0..len];
     const alloc = std.heap.page_allocator;
+    var threaded_io: std.Io.Threaded = .init(alloc, .{});
+    const io = threaded_io.io();
 
     // Number of columns to render (output width).
     // We handle the case of the user not providing the argument by defaulting to 100.
@@ -80,7 +82,7 @@ export fn render_markdown(lua: ?*LuaState) callconv(.c) c_int {
         .max_image_cols = if (columns > 4) @intCast(columns - 4) else @intCast(columns),
         .termsize = tsize,
     };
-    var r_renderer = zd.render.RangeRenderer.init(&alloc_writer.writer, alloc, render_opts);
+    var r_renderer = zd.render.RangeRenderer.init(io, alloc, &alloc_writer.writer, render_opts);
     defer r_renderer.deinit();
     r_renderer.renderBlock(md) catch @panic("Render error!");