feat: migrate to Zig 0.16

[apotema]

Summary

• Bumps minimum_zig_version to 0.16.0
• @Type(.{ .@"struct" }) → @Struct(...) in zon_coercion.zig (with StructField.Attributes reshaping)
• std.testing.refAllDeclsRecursive → refAllDecls
• Bumps zspec to apotema/zspec 0.16 branch

Status

• zig build: ✅ PASS
• zig build test: ✅ PASS

[apotema]

@copilot review

[Copilot]

@copilot review

Reviewed the current PR state at 2de40f9. I didn’t find any additional actionable issues from this pass, so no further code changes were needed.

[gemini-code-assist]

Code Review

This pull request migrates the project to Zig 0.16.0, updating the minimum version and dependencies in build.zig.zon. In src/zon_coercion.zig, the MergedStructType function was refactored to use the new @Struct builtin and separate arrays for field metadata. Feedback for this refactor suggests optimizing the field lookup logic using std.meta.fieldInfo to avoid nested loops, preserving original field alignments instead of recalculating them, and using more idiomatic syntax for empty declarations in the @Struct call.

[gemini-code-assist]

The current implementation of MergedStructType uses a nested inline for loop to find override types, resulting in $O(N \cdot M)$ complexity at comptime. This can be simplified and optimized using std.meta.fieldInfo to directly access field metadata by name. Additionally, using the actual alignment from the source fields (bf.alignment, of.alignment, or info.alignment) is preferred over forcing @alignOf(type) to ensure any custom alignment specified in the original types is preserved. Finally, for the @Struct call, passing &.{} instead of null for the declarations argument is more idiomatic for a struct with no declarations.

    comptime var field_names: [field_count][]const u8 = undefined;
    comptime var field_types: [field_count]type = undefined;
    comptime var field_attrs: [field_count]std.builtin.Type.StructField.Attributes = undefined;
    comptime var i = 0;

    inline for (base_fields) |bf| {
        field_names[i] = bf.name;
        if (@hasField(OverridesType, bf.name)) {
            const info = std.meta.fieldInfo(OverridesType, bf.name);
            field_types[i] = info.type;
            field_attrs[i] = .{ .@"align" = info.alignment };
        } else {
            field_types[i] = bf.type;
            field_attrs[i] = .{ .@"align" = bf.alignment };
        }
        i += 1;
    }

    inline for (override_fields) |of| {
        if (!@hasField(BaseType, of.name)) {
            field_names[i] = of.name;
            field_types[i] = of.type;
            field_attrs[i] = .{ .@"align" = of.alignment };
            i += 1;
        }
    }

    return @Struct(.auto, &.{}, &field_names, &field_types, &field_attrs);

[cursor]

PR Summary

Medium Risk
Bumps the compiler/toolchain baseline to Zig 0.16 and updates dependent tooling/APIs, which can introduce build or comptime behavior differences across the project despite minimal logic changes.

Overview
Migrates the project to Zig 0.16 by bumping the CI toolchain and build.zig.zon minimum_zig_version, and updating the zspec dependency to v0.9.1.

Updates comptime struct-type construction in zon_coercion.zig from @Type(.{ .@"struct" = ... }) to the new @Struct(...) API (including StructField.Attributes handling), and adjusts tests to use std.testing.refAllDecls instead of refAllDeclsRecursive.

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[cursor]

Cursor Bugbot has reviewed your changes and found 1 potential issue.

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[cursor]

Switching to refAllDecls silently skips all nested tests

High Severity

Changing refAllDeclsRecursive to refAllDecls silently disables the entire test suite. Every test file uses zspec's nested-struct pattern (e.g., pub const AStarSpec = struct { pub const basic_pathfinding = struct { test "..." { … } } }), with zero top-level test blocks. refAllDecls only references the direct @import declarations without recursing into the nested structs, so the compiler never analyzes the inner test blocks. The zig build test passes vacuously — the single unnamed test in root.zig succeeds, but none of the actual test logic runs.

 

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