Phase 1: Populate reusedCode from USWDS and CMS Design System dependencies

src/__tests__/unit/helper.test.ts

@@ -1,8 +1,29 @@
 import { describe, it, expect, jest, beforeEach } from "@jest/globals";
-import { createHelpers } from "../../helper.js";
+import {
+  createHelpers,
+  parsePackageJSON,
+  parseRequirementsTxt,
+  mergeReusedCode,
+} from "../../helper.js";
+import {
+  GOV_DEPENDENCIES,
+  USWDS,
+  USWDS_COMPILE,
+  CMS_DESIGN_SYSTEM,
+  CMS_DS_HEALTHCARE_GOV,
+} from "../../gov-dependencies.js";
 import { createMockDeps, createMockOctokit } from "../fixtures/mock-deps.js";
 import { Dependencies } from "../../types/Dependencies.js";
 
+// returns a readFile mock that serves content by filepath and rejects otherwise
+function readFileFrom(files: Record<string, string>) {
+  return jest.fn<any>((filepath: string) =>
+    filepath in files
+      ? Promise.resolve(files[filepath])
+      : Promise.reject(new Error("ENOENT")),
+  );
+}
+
 describe("createHelpers - calculateMetaData", () => {
   let deps: Dependencies;
 
@@ -203,4 +224,197 @@ describe("createHelpers - validateOnly", () => {
     expect(deps.setFailed).not.toHaveBeenCalled();
     expect(deps.log.info).toHaveBeenCalledWith("code.json is valid!");
   });
+});
+
+describe("parsePackageJSON", () => {
+  it("collects dependencies and devDependencies", () => {
+    const content = JSON.stringify({
+      dependencies: { uswds: "^3.0.0", react: "^18.0.0" },
+      devDependencies: { jest: "^29.0.0" },
+    });
+    expect(parsePackageJSON(content)).toEqual(["uswds", "react", "jest"]);
+  });
+
+  it("handles missing dependency sections", () => {
+    expect(parsePackageJSON(JSON.stringify({ name: "x" }))).toEqual([]);
+  });
+
+  it("returns empty array for invalid JSON", () => {
+    expect(parsePackageJSON("not json {{{")).toEqual([]);
+  });
+});
+
+describe("parseRequirementsTxt", () => {
+  it("strips version specifiers, extras, markers and comments", () => {
+    const content = [
+      "uswds==3.0.0",
+      "requests>=2.0  # http client",
+      "django[argon2]~=4.2",
+      'pytz; python_version < "3.9"',
+      "# a comment line",
+      "",
+      "-r other-requirements.txt",
+      "--hash=sha256:abc",
+    ].join("\n");
+
+    expect(parseRequirementsTxt(content)).toEqual([
+      "uswds",
+      "requests",
+      "django",
+      "pytz",
+    ]);
+  });
+});
+
+describe("createHelpers - detectReusedCode", () => {
+  it("matches a known gov dependency from package.json", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { "@uswds/uswds": "^3.0.0", react: "^18.0.0" },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([USWDS]);
+  });
+
+  it("matches a known gov dependency from requirements.txt", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/requirements.txt": "uswds==3.0.0\nrequests==2.0",
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([USWDS]);
+  });
+
+  it("matches multiple distinct gov dependencies in one manifest", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: {
+            "@uswds/uswds": "^3.0.0",
+            "@cmsgov/design-system": "^14.0.0",
+            react: "^18.0.0",
+          },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([
+      USWDS,
+      CMS_DESIGN_SYSTEM,
+    ]);
+  });
+
+  it("lists @uswds/compile as a separate entry from @uswds/uswds", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { "@uswds/uswds": "^3.0.0" },
+          devDependencies: { "@uswds/compile": "^1.0.0" },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([
+      USWDS,
+      USWDS_COMPILE,
+    ]);
+  });
+
+  it("lists each CMS dependency individually", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { "@cmsgov/design-system": "^14.0.0" },
+          devDependencies: { "@cmsgov/ds-healthcare-gov": "^18.0.0" },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([
+      CMS_DESIGN_SYSTEM,
+      CMS_DS_HEALTHCARE_GOV,
+    ]);
+  });
+
+  it("dedupes the same dependency found across both manifests", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { "@uswds/uswds": "^3.0.0" },
+        }),
+        "/github/workspace/requirements.txt": "uswds==3.0.0",
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([USWDS]);
+  });
+
+  it("returns empty when no manifests are present", async () => {
+    const deps = createMockDeps();
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([]);
+  });
+
+  it("returns empty when no known gov dependencies are found", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { react: "^18.0.0" },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([]);
+  });
+
+  it("ignores dependency names that collide with Object prototype members", async () => {
+    const deps = createMockDeps({
+      readFile: readFileFrom({
+        "/github/workspace/package.json": JSON.stringify({
+          dependencies: { constructor: "1.0.0", valueOf: "1.0.0" },
+        }),
+      }),
+    });
+
+    expect(await createHelpers(deps).detectReusedCode()).toEqual([]);
+  });
+});
+
+describe("mergeReusedCode", () => {
+  it("appends detected entries to existing ones", () => {
+    const existing = [{ name: "Other Gov Tool", URL: "https://example.gov" }];
+    expect(mergeReusedCode(existing, [USWDS])).toEqual([...existing, USWDS]);
+  });
+
+  it("does not duplicate an entry already present by URL", () => {
+    const existing = [{ name: "USWDS (manual)", URL: USWDS.URL }];
+    expect(mergeReusedCode(existing, [USWDS])).toEqual(existing);
+  });
+
+  it("does not duplicate an entry already present by name", () => {
+    const existing = [{ name: USWDS.name, URL: "https://old.example" }];
+    expect(mergeReusedCode(existing, [USWDS])).toEqual(existing);
+  });
+
+  it("returns existing unchanged when nothing is detected", () => {
+    const existing = [{ name: "Gov Tool", URL: "https://example.gov" }];
+    expect(mergeReusedCode(existing, [])).toEqual(existing);
+  });
+
+  it("tolerates a non-array existing value", () => {
+    expect(mergeReusedCode(undefined as any, [USWDS])).toEqual([USWDS]);
+  });
+});
+
+describe("GOV_DEPENDENCIES integrity", () => {
+  const entries = Object.entries(GOV_DEPENDENCIES);
+
+  it.each(entries)("%s has a lowercase key and a valid entry", (key, entry) => {
+    expect(key).toBe(key.toLowerCase());
+    expect(entry.name.trim()).not.toBe("");
+    expect(entry.URL).toMatch(/^https:\/\//);
+  });
 });

src/gov-dependencies.ts

@@ -0,0 +1,59 @@
+export interface ReusedCodeEntry {
+  name: string;
+  URL: string;
+}
+
+// each dependency gets its own entry with the repository URL where the source code is hosted
+export const USWDS: ReusedCodeEntry = {
+  name: "U.S. Web Design System (USWDS)",
+  URL: "https://github.com/uswds/uswds",
+};
+
+export const USWDS_COMPILE: ReusedCodeEntry = {
+  name: "USWDS Compile",
+  URL: "https://github.com/uswds/uswds-compile",
+};
+
+export const CMS_DESIGN_SYSTEM: ReusedCodeEntry = {
+  name: "CMS Design System",
+  URL: "https://github.com/CMSgov/design-system",
+};
+
+export const CMS_DS_HEALTHCARE_GOV: ReusedCodeEntry = {
+  name: "CMS Design System - HealthCare.gov",
+  URL: "https://github.com/CMSgov/design-system/tree/main/packages/ds-healthcare-gov",
+};
+
+export const CMS_DS_MEDICARE_GOV: ReusedCodeEntry = {
+  name: "CMS Design System - Medicare.gov",
+  URL: "https://github.com/CMSgov/design-system/tree/main/packages/ds-medicare-gov",
+};
+
+export const CMS_DS_CMS_GOV: ReusedCodeEntry = {
+  name: "CMS Design System - CMS.gov",
+  URL: "https://github.com/CMSgov/design-system/tree/main/packages/ds-cms-gov",
+};
+
+// keys are lowercased package names; each maps to its own unique entry
+export const GOV_DEPENDENCIES: Record<string, ReusedCodeEntry> = {
+  uswds: USWDS,
+  "@uswds/uswds": USWDS,
+  "@uswds/compile": USWDS_COMPILE,
+  "@cmsgov/design-system": CMS_DESIGN_SYSTEM,
+  "@cmsgov/ds-healthcare-gov": CMS_DS_HEALTHCARE_GOV,
+  "@cmsgov/ds-medicare-gov": CMS_DS_MEDICARE_GOV,
+  "@cmsgov/ds-cms-gov": CMS_DS_CMS_GOV,
+};
+
+// npm names are lowercase and Python names are case-insensitive, so lowercasing suffices to match
+export function normalizePackageName(name: string): string {
+  return name.trim().toLowerCase();
+}
+
+export function lookupGovDependency(name: string): ReusedCodeEntry | undefined {
+  // hasOwn guard so names like "constructor"/"__proto__" don't match inherited members
+  const key = normalizePackageName(name);
+  return Object.hasOwn(GOV_DEPENDENCIES, key)
+    ? GOV_DEPENDENCIES[key]
+    : undefined;
+}