test(miner): close patch-coverage gaps in the bounded policy-doc reader

Covers the streaming reader's normal-completion path (never exercised --
existing tests only hit the non-stream fallback and the overflow-cancel
branch), plus the non-numeric content-length and oversized-non-streamed-body
branches.

Author: JSONbored

test/unit/miner-rejection-signal.test.ts

@@ -91,6 +91,46 @@ describe("resolveRejectionSignaled (#5132)", () => {
     expect(text).not.toHaveBeenCalled();
   });
 
+  it("ignores a non-numeric content-length header and falls through to reading the body", async () => {
+    const fetchImpl = routedFetch({
+      "AI-USAGE.md": () => ({
+        ok: true,
+        status: 200,
+        headers: new Headers({ "content-length": "not-a-number" }),
+        json: async (): Promise<unknown> => {
+          throw new Error("json() is unused by resolveRejectionSignaled");
+        },
+        text: async () => "No AI-generated pull requests, please.",
+      }),
+      "CONTRIBUTING.md": () => textResponse("Welcome, contributors!"),
+    });
+
+    const result = await resolveRejectionSignaled("acme/widgets", { fetchImpl });
+
+    expect(result).toBe(true);
+  });
+
+  it("treats an oversized non-streamed policy document as absent", async () => {
+    const oversizedText = "a".repeat(129 * 1024);
+    const fetchImpl = routedFetch({
+      "AI-USAGE.md": () => ({
+        ok: true,
+        status: 200,
+        headers: new Headers(),
+        json: async (): Promise<unknown> => {
+          throw new Error("json() is unused by resolveRejectionSignaled");
+        },
+        text: async () => oversizedText,
+      }),
+      "CONTRIBUTING.md": () => textResponse("Do not submit AI-generated code."),
+    });
+
+    const result = await resolveRejectionSignaled("acme/widgets", { fetchImpl });
+
+    // AI-USAGE.md is treated as absent (oversized), so the verdict falls through to CONTRIBUTING.md's ban.
+    expect(result).toBe(true);
+  });
+
   it("cancels a streamed policy document once it exceeds the byte limit", async () => {
     let canceled = false;
     const chunk = new Uint8Array(65 * 1024);
@@ -125,6 +165,36 @@ describe("resolveRejectionSignaled (#5132)", () => {
     expect(canceled).toBe(true);
   });
 
+  it("reads a streamed policy document to completion when it stays within the byte limit", async () => {
+    const encoder = new TextEncoder();
+    const stream = new ReadableStream({
+      start(controller) {
+        controller.enqueue(encoder.encode("No AI-generated "));
+        controller.enqueue(encoder.encode("pull requests, please."));
+        controller.close();
+      },
+    });
+    const fetchImpl = routedFetch({
+      "AI-USAGE.md": () => ({
+        ok: true,
+        status: 200,
+        headers: new Headers(),
+        body: stream,
+        json: async (): Promise<unknown> => {
+          throw new Error("json() is unused by resolveRejectionSignaled");
+        },
+        text: async () => {
+          throw new Error("streaming responses should not call text()");
+        },
+      }),
+      "CONTRIBUTING.md": () => textResponse("Welcome, contributors!"),
+    });
+
+    const result = await resolveRejectionSignaled("acme/widgets", { fetchImpl });
+
+    expect(result).toBe(true);
+  });
+
   it("fails open to false when both docs 404", async () => {
     const fetchImpl = routedFetch({});
     const result = await resolveRejectionSignaled("acme/widgets", { fetchImpl });