test(reference): pin excluded package main resolution (#7941)

tests/boundary/cli/referenceSourceExcludedPackageManifest.test.ts

@@ -62,3 +62,117 @@ cliTest(
     );
   },
 );
+
+cliTest(
+  "does not fall back to an index when the declared main is excluded",
+  async ({ cli }) => {
+    const root = await createTestTempDirectory("rea-reference-excluded-main-");
+    const config = await createTestTempDirectory(
+      "rea-reference-excluded-main-config-",
+    );
+    await Promise.all([
+      mkdir(join(root, "excluded", "dist"), { recursive: true }),
+      mkdir(join(root, "visible", "lib"), { recursive: true }),
+      mkdir(join(root, "missing"), { recursive: true }),
+      mkdir(join(root, "ignored", "lib"), { recursive: true }),
+    ]);
+    await Promise.all([
+      writeFile(join(root, ".gitignore"), "ignored/lib/entry.js\n"),
+      writeFile(
+        join(root, "main.cjs"),
+        'require("./excluded"); require("./visible"); require("./missing"); require("./ignored");\n',
+      ),
+      writeFile(
+        join(root, "excluded", "package.json"),
+        '{"main":"dist/index.js"}',
+      ),
+      writeFile(
+        join(root, "excluded", "dist", "index.js"),
+        "module.exports = 1;",
+      ),
+      writeFile(join(root, "excluded", "index.js"), "module.exports = 2;"),
+      writeFile(
+        join(root, "visible", "package.json"),
+        '{"main":"lib/index.js"}',
+      ),
+      writeFile(
+        join(root, "visible", "lib", "index.js"),
+        "module.exports = 3;",
+      ),
+      writeFile(join(root, "visible", "index.js"), "module.exports = 4;"),
+      writeFile(join(root, "missing", "package.json"), '{"main":"gone.js"}'),
+      writeFile(join(root, "missing", "index.js"), "module.exports = 5;"),
+      writeFile(
+        join(root, "ignored", "package.json"),
+        '{"main":"lib/entry.js"}',
+      ),
+      writeFile(
+        join(root, "ignored", "lib", "entry.js"),
+        "module.exports = 6;",
+      ),
+      writeFile(join(root, "ignored", "index.js"), "module.exports = 7;"),
+    ]);
+    const result = await cli.run({
+      arguments: ["import-reference-source", root, "--json"],
+      environment: {
+        HOME: config,
+        XDG_CONFIG_HOME: config,
+        XDG_CACHE_HOME: config,
+      },
+    });
+    expect(result.exitCode, result.stderr + JSON.stringify(result.json)).toBe(
+      0,
+    );
+    const graph = historicalSourceGraphSchema.parse(result.json);
+    expect(graph.exclusions).toContainEqual({
+      path: "excluded/dist",
+      entry_kind: "directory",
+      reason: "default-ignored",
+      pattern: "dist/",
+    });
+    expect(graph.exclusions).toContainEqual({
+      path: "ignored/lib/entry.js",
+      entry_kind: "file",
+      reason: "project-ignored",
+      pattern: "ignored/lib/entry.js",
+    });
+    expect(graph.relationships).toEqual(
+      expect.arrayContaining([
+        expect.objectContaining({
+          from_path: "main.cjs",
+          to: "excluded",
+          resolution: "unresolved",
+        }),
+        expect.objectContaining({
+          from_path: "main.cjs",
+          to: "visible/lib/index.js",
+          resolution: "internal",
+        }),
+        expect.objectContaining({
+          from_path: "main.cjs",
+          to: "missing/index.js",
+          resolution: "internal",
+        }),
+        expect.objectContaining({
+          from_path: "main.cjs",
+          to: "ignored",
+          resolution: "unresolved",
+        }),
+      ]),
+    );
+    expect(graph.relationships).not.toContainEqual(
+      expect.objectContaining({
+        from_path: "main.cjs",
+        to: "excluded/index.js",
+        resolution: "internal",
+      }),
+    );
+    expect(graph.relationships).not.toContainEqual(
+      expect.objectContaining({
+        from_path: "main.cjs",
+        to: "ignored/index.js",
+        resolution: "internal",
+      }),
+    );
+  },
+);