Remove @cImport

See ziglang/zig#20630

Author: luchak

Diff for: build.zig

@@ -51,8 +51,9 @@ pub fn build(b: *Build) void {
         else => buildLua(b, target, optimize, upstream, lang, shared),
     };
 
-    // Expose the Lua artifact
-    b.installArtifact(lib);
+    // Expose the Lua artifact, and get an install step that header translation can refer to
+    const install_lib = b.addInstallArtifact(lib, .{});
+    b.getInstallStep().dependOn(&install_lib.step);
 
     switch (lang) {
         .luau => {
@@ -66,6 +67,21 @@ pub fn build(b: *Build) void {
 
     ziglua.linkLibrary(lib);
 
+    // lib must expose all headers included by these root headers
+    const c_header_path = switch (lang) {
+        .luajit => b.path("include/luajit_all.h"),
+        .luau => b.path("include/luau_all.h"),
+        else => b.path("include/lua_all.h"),
+    };
+    const c_headers = b.addTranslateC(.{
+        .root_source_file = c_header_path,
+        .target = target,
+        .optimize = optimize,
+    });
+    c_headers.addIncludeDir(b.getInstallPath(install_lib.h_dir.?, ""));
+    c_headers.step.dependOn(&install_lib.step);
+    ziglua.addImport("c", c_headers.createModule());
+
     // Tests
     const tests = b.addTest(.{
         .root_source_file = b.path("src/tests.zig"),
@@ -222,10 +238,10 @@ fn buildLuau(b: *Build, target: Build.ResolvedTarget, optimize: std.builtin.Opti
     lib.addCSourceFile(.{ .file = b.path("src/luau.cpp"), .flags = &flags });
     lib.linkLibCpp();
 
-    // It may not be as likely that other software links against Luau, but might as well expose these anyway
     lib.installHeader(upstream.path("VM/include/lua.h"), "lua.h");
     lib.installHeader(upstream.path("VM/include/lualib.h"), "lualib.h");
     lib.installHeader(upstream.path("VM/include/luaconf.h"), "luaconf.h");
+    lib.installHeader(upstream.path("Compiler/include/luacode.h"), "luacode.h");
 
     return lib;
 }

Diff for: include/lua_all.h

@@ -0,0 +1,9 @@
+#ifndef lua_all_h
+#define lua_all_h
+
+#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"
+#include "luaconf.h"
+
+#endif // lua_all_h

Diff for: include/luajit_all.h

@@ -0,0 +1,10 @@
+#ifndef luajit_all_h
+#define luajit_all_h
+
+#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"
+#include "luaconf.h"
+#include "luajit.h"
+
+#endif // luajit_all_h

Diff for: include/luau_all.h

@@ -0,0 +1,9 @@
+#ifndef luau_all_h
+#define luau_all_h
+
+#include "lua.h"
+#include "lualib.h"
+#include "luaconf.h"
+#include "luacode.h"
+
+#endif // luau_all_h

Diff for: src/lib.zig

@@ -1,14 +1,6 @@
 const std = @import("std");
 
-const c = @cImport({
-    @cInclude("luaconf.h");
-    @cInclude("lua.h");
-    @cInclude("lualib.h");
-
-    if (lang != .luau) @cInclude("lauxlib.h");
-    if (lang == .luau) @cInclude("luacode.h");
-    if (lang == .luajit) @cInclude("luajit.h");
-});
+const c = @import("c");
 
 const config = @import("config");