conformance(v2:shred): local conformance for v2 shred parse harness

build.zig

@@ -317,53 +317,69 @@ const Sig = struct {
         });
         unit_tests.add("lib", lib);
 
-        // Components: one per subdir of v2/components/. Each gets lib, tracy, and build-options
+        // Components: one per subdir of v2/components/. Each gets lib, tracy, and build-options.
+        //
+        // A component's impl (component.zig + siblings) may opt into a sibling
+        // component's api via `extra_api_deps`. The `_api` module itself always
+        // stays isolated to lib/tracy/build-options so the public surface is
+        // guaranteed cycle-free.
+        const extra_api_deps = std.StaticStringMap([]const []const u8).initComptime(&.{
+            .{ "replay", &.{"shred_api"} },
+        });
+
+        const component_base_imports: []const Build.Module.Import = &.{
+            .{ .name = "lib", .module = lib },
+            .{ .name = "tracy", .module = deps.tracy },
+            .{ .name = "build-options", .module = build_options_mod },
+        };
+
+        const Pending = struct { name: []const u8, comp_dir: []const u8, api: *Build.Module };
+        var pending: std.ArrayList(Pending) = .empty;
         var components: std.StringHashMapUnmanaged(Component) = .empty;
         var api_import_list: std.ArrayList(Build.Module.Import) = .empty;
+
+        // Pass 1: build every api so pass 2's sibling lookups can't miss.
         {
-            var dir = try b.build_root.handle.openDir(
-                "v2/components",
-                .{ .iterate = true },
-            );
+            var dir = try b.build_root.handle.openDir("v2/components", .{ .iterate = true });
             defer dir.close();
             var it = dir.iterate();
             while (try it.next()) |entry| {
                 if (entry.kind != .directory) continue;
                 if (std.mem.eql(u8, entry.name, "runtime")) continue;
                 const name = b.dupe(entry.name);
-
                 const comp_dir = b.fmt("v2/components/{s}", .{name});
-                const imports: []const Build.Module.Import = &.{
-                    .{ .name = "lib", .module = lib },
-                    .{ .name = "tracy", .module = deps.tracy },
-                    .{ .name = "build-options", .module = build_options_mod },
-                };
-
                 const api_name = b.fmt("{s}_api", .{name});
                 const api = b.addModule(api_name, .{
                     .root_source_file = b.path(b.fmt("{s}/api.zig", .{comp_dir})),
                     .target = config.target,
                     .optimize = config.optimize,
-                    .imports = imports,
+                    .imports = component_base_imports,
                 });
                 unit_tests.add(api_name, api);
-
-                const component = b.addModule(name, .{
-                    .root_source_file = b.path(b.fmt("{s}/component.zig", .{comp_dir})),
-                    .target = config.target,
-                    .optimize = config.optimize,
-                    .imports = concatImports(b, &.{
-                        imports,
-                        &.{.{ .name = "api", .module = api }},
-                    }),
-                });
-                unit_tests.add(name, component);
-
-                try components.put(b.allocator, name, .{ .api = api, .component = component });
                 try api_import_list.append(b.allocator, .{ .name = api_name, .module = api });
+                try pending.append(b.allocator, .{ .name = name, .comp_dir = comp_dir, .api = api });
             }
         }
 
+        // Pass 2: build each component impl module.
+        for (pending.items) |p| {
+            var imports: std.ArrayList(Build.Module.Import) = .empty;
+            try imports.appendSlice(b.allocator, component_base_imports);
+            try imports.append(b.allocator, .{ .name = "api", .module = p.api });
+            for (extra_api_deps.get(p.name) orelse &.{}) |extra| {
+                try imports.append(b.allocator, findApi(api_import_list.items, extra));
+            }
+
+            const component = b.addModule(p.name, .{
+                .root_source_file = b.path(b.fmt("{s}/component.zig", .{p.comp_dir})),
+                .target = config.target,
+                .optimize = config.optimize,
+                .imports = imports.items,
+            });
+            unit_tests.add(p.name, component);
+            try components.put(b.allocator, p.name, .{ .api = p.api, .component = component });
+        }
+
         // runtime is special cased because it needs codegen and a bunch of extra deps that
         // no other component uses.
         const runtime = addRuntime(b, config, deps, unit_tests, lib, features_zon, feature_set_id);
@@ -594,6 +610,13 @@ fn concatImports(
     return out;
 }
 
+fn findApi(imports: []const Build.Module.Import, name: []const u8) Build.Module.Import {
+    for (imports) |imp| {
+        if (std.mem.eql(u8, imp.name, name)) return imp;
+    }
+    std.debug.panic("extra_api_deps references unknown api '{s}'", .{name});
+}
+
 /// Everything other than Sig itself: developer tools, ci scripts, docs,
 /// integration tests, etc.
 const Tools = struct {

conformance/build.zig

@@ -93,6 +93,8 @@ pub fn build(b: *Build) void {
     const sig_v2_mod = sig_v2_dep.module("lib");
     const shred_api_mod = sig_v2_dep.module("shred_api");
     const shred_mod = sig_v2_dep.module("shred");
+    const replay_api_mod = sig_v2_dep.module("replay_api");
+    const replay_mod = sig_v2_dep.module("replay");
 
     const pb_dep = b.dependency("pb", .{
         .target = target,
@@ -105,6 +107,8 @@ pub fn build(b: *Build) void {
         .{ .name = "sig_v2", .module = sig_v2_mod },
         .{ .name = "shred_api", .module = shred_api_mod },
         .{ .name = "shred", .module = shred_mod },
+        .{ .name = "replay_api", .module = replay_api_mod },
+        .{ .name = "replay", .module = replay_mod },
         .{ .name = "protobuf", .module = pb_mod },
         .{ .name = "build-options", .module = build_options.createModule() },
     };