packages/fabric/core/src/variant/is-variant.spec.ts

@@ -1,40 +0,0 @@
-import { describe, expect, expectTypeOf, it } from "vitest";
-import { isVariant } from "./is-variant.js";
-import { TaggedVariant, VariantTag } from "./variant.js";
-
-interface SuccessVariant extends TaggedVariant<"success"> {
-  [VariantTag]: "success";
-  data: string;
-}
-
-interface ErrorVariant extends TaggedVariant<"error"> {
-  [VariantTag]: "error";
-  message: string;
-}
-
-describe("isVariant", () => {
-  const successVariant = {
-    [VariantTag]: "success",
-    data: "Operation successful",
-  } as SuccessVariant | ErrorVariant;
-
-  const errorVariant = {
-    [VariantTag]: "error",
-    message: "Operation failed",
-  } as SuccessVariant | ErrorVariant;
-
-  it("should return true for a matching tag and correctly infer it", () => {
-    if (isVariant(successVariant, "success")) {
-      expectTypeOf(successVariant).toEqualTypeOf<SuccessVariant>();
-    }
-
-    if (isVariant(errorVariant, "error")) {
-      expectTypeOf(errorVariant).toEqualTypeOf<ErrorVariant>();
-    }
-  });
-
-  it("should return false for a non-matching tag", () => {
-    expect(isVariant(successVariant, "error")).toBe(false);
-    expect(isVariant(errorVariant, "success")).toBe(false);
-  });
-});

packages/fabric/core/src/variant/is-variant.ts

@@ -1,11 +0,0 @@
-import { TaggedVariant, VariantTag } from "./variant.js";
-
-export function isVariant<
-  TVariant extends TaggedVariant<string>,
-  TTag extends TVariant[VariantTag],
->(
-  variant: TVariant,
-  tag: TTag,
-): variant is Extract<TVariant, { [VariantTag]: TTag }> {
-  return variant[VariantTag] === tag;
-}

packages/fabric/core/src/variant/variant.spec.ts

@@ -0,0 +1,41 @@
+import { describe, expect, expectTypeOf, it } from "vitest";
+import { TaggedVariant, Variant, VariantTag } from "./variant.js";
+
+interface SuccessVariant extends TaggedVariant<"success"> {
+  [VariantTag]: "success";
+  data: string;
+}
+
+interface ErrorVariant extends TaggedVariant<"error"> {
+  [VariantTag]: "error";
+  message: string;
+}
+
+describe("Variant", () => {
+  describe("isVariant", () => {
+    const successVariant = {
+      [VariantTag]: "success",
+      data: "Operation successful",
+    } as SuccessVariant | ErrorVariant;
+
+    const errorVariant = {
+      [VariantTag]: "error",
+      message: "Operation failed",
+    } as SuccessVariant | ErrorVariant;
+
+    it("should return true for a matching tag and correctly infer it", () => {
+      if (Variant.is(successVariant, "success")) {
+        expectTypeOf(successVariant).toEqualTypeOf<SuccessVariant>();
+      }
+
+      if (Variant.is(errorVariant, "error")) {
+        expectTypeOf(errorVariant).toEqualTypeOf<ErrorVariant>();
+      }
+    });
+
+    it("should return false for a non-matching tag", () => {
+      expect(Variant.is(successVariant, "error")).toBe(false);
+      expect(Variant.is(errorVariant, "success")).toBe(false);
+    });
+  });
+});

packages/fabric/core/src/variant/variant.ts

@@ -9,3 +9,15 @@ export type VariantFromTag<
   TVariant extends TaggedVariant<string>,
   TTag extends TVariant[typeof VariantTag],
 > = Extract<TVariant, { [VariantTag]: TTag }>;
+
+export namespace Variant {
+  export function is<
+    TVariant extends TaggedVariant<string>,
+    TTag extends TVariant[VariantTag],
+  >(
+    variant: TVariant,
+    tag: TTag,
+  ): variant is Extract<TVariant, { [VariantTag]: TTag }> {
+    return variant[VariantTag] === tag;
+  }
+}