tests: hard code read_buf_cap to 4096

* necessary for zig version 0.14.0-dev.3239+d7b93c787 where
  mem.page_size moved to heap.pageSize() and isn't always
  comptime known

bench/twitter/main.zig

@@ -1,7 +1,8 @@
 const std = @import("std");
+
 const dom = @import("simdjzon").dom;
 
-pub const read_buf_cap = std.mem.page_size;
+pub const read_buf_cap = 4096;
 
 pub fn main() !u8 {
     var arena = std.heap.ArenaAllocator.init(std.heap.page_allocator);
@@ -21,8 +22,8 @@ pub fn main() !u8 {
     const array = try statuses.get_array();
     var i: usize = 0;
     while (array.at(i)) |status| : (i += 1) {
-        _ = status; // autofix
-        // const id = try status.at_pointer("/id");
+        const id = try status.at_pointer("/id");
+        std.mem.doNotOptimizeAway(id);
         // std.debug.print("{}\n", .{try id.get_int64()});
     }
     // std.debug.print("i={}\n", .{i});

src/ondemand.zig

@@ -15,18 +15,18 @@ const CharUtils = string_parsing.CharUtils;
 
 /// Users must specify `pub const read_buf_cap = N;` in their root source file.
 /// This sets the static `ondemand.Parser.read_buf` size.  `read_buf` is
-/// where chunks of json source are stored.  recommended `std.mem.page_size`.
+/// where chunks of json source are stored.  recommended `std.heap.pageSize()`.
 /// Larger `read_buf_cap` may improve performance for large json files.
 pub const READ_BUF_CAP = if (@hasDecl(root, "read_buf_cap"))
     root.read_buf_cap
 else if (builtin.is_test)
-    mem.page_size
+    4096
 else
     @compileError(
         \\root source file is missing a `pub const read_buf_cap` declaration.
         \\This sets the static `ondemand.Parser.read_buf` size.  `read_buf` is
         \\where chunks of json source are stored.  recommended
-        \\`std.mem.page_size`.
+        \\`std.heap.pageSize()`.
         \\
     );
 

src/tests.zig

@@ -1,14 +1,14 @@
 const std = @import("std");
 const testing = std.testing;
 const mem = std.mem;
+const allr = testing.allocator;
 
-const TapeType = dom.TapeType;
 const simdjzon = @import("simdjzon");
 const dom = simdjzon.dom;
 const ondemand = simdjzon.ondemand;
 const cmn = simdjzon.common;
+const TapeType = dom.TapeType;
 
-const allr = testing.allocator;
 test "tape build 1" {
     std.debug.print("\n", .{});
     const f = try std.fs.cwd().openFile("test/test.json", .{});