From 12cbaddadeec5712810c75ed8628ca0ef1f8f96c Mon Sep 17 00:00:00 2001
From: Peter Steinberger <steipete@gmail.com>
Date: Fri, 13 Mar 2026 19:37:49 +0000
Subject: [PATCH] test: expand runtime guard and path prepend coverage

---
 src/infra/path-prepend.test.ts  | 33 +++++++++++++++++++++++++++++++++
 src/infra/runtime-guard.test.ts | 27 +++++++++++++++++++++++++++
 2 files changed, 60 insertions(+)
 create mode 100644 src/infra/path-prepend.test.ts

diff --git a/src/infra/path-prepend.test.ts b/src/infra/path-prepend.test.ts
new file mode 100644
index 000000000..29dfb504c
--- /dev/null
+++ b/src/infra/path-prepend.test.ts
@@ -0,0 +1,33 @@
+import path from "node:path";
+import { describe, expect, it } from "vitest";
+import { mergePathPrepend, normalizePathPrepend } from "./path-prepend.js";
+
+describe("path prepend helpers", () => {
+  it("normalizes prepend lists by trimming, skipping blanks, and deduping", () => {
+    expect(
+      normalizePathPrepend([
+        " /custom/bin ",
+        "",
+        " /custom/bin ",
+        "/opt/bin",
+        // oxlint-disable-next-line typescript/no-explicit-any
+        42 as any,
+      ]),
+    ).toEqual(["/custom/bin", "/opt/bin"]);
+    expect(normalizePathPrepend()).toEqual([]);
+  });
+
+  it("merges prepended paths ahead of existing values without duplicates", () => {
+    expect(mergePathPrepend(`/usr/bin${path.delimiter}/opt/bin`, ["/custom/bin", "/usr/bin"])).toBe(
+      ["/custom/bin", "/usr/bin", "/opt/bin"].join(path.delimiter),
+    );
+    expect(mergePathPrepend(undefined, ["/custom/bin"])).toBe("/custom/bin");
+    expect(mergePathPrepend("/usr/bin", [])).toBe("/usr/bin");
+  });
+
+  it("trims existing path entries while preserving order", () => {
+    expect(
+      mergePathPrepend(` /usr/bin ${path.delimiter} ${path.delimiter} /opt/bin `, ["/custom/bin"]),
+    ).toBe(["/custom/bin", "/usr/bin", "/opt/bin"].join(path.delimiter));
+  });
+});
diff --git a/src/infra/runtime-guard.test.ts b/src/infra/runtime-guard.test.ts
index 410fe5d4a..ca1080b84 100644
--- a/src/infra/runtime-guard.test.ts
+++ b/src/infra/runtime-guard.test.ts
@@ -4,6 +4,7 @@ import {
   detectRuntime,
   isAtLeast,
   parseSemver,
+  isSupportedNodeVersion,
   type RuntimeDetails,
   runtimeSatisfies,
 } from "./runtime-guard.js";
@@ -12,6 +13,7 @@ describe("runtime-guard", () => {
   it("parses semver with or without leading v", () => {
     expect(parseSemver("v22.1.3")).toEqual({ major: 22, minor: 1, patch: 3 });
     expect(parseSemver("1.3.0")).toEqual({ major: 1, minor: 3, patch: 0 });
+    expect(parseSemver("22.16.0-beta.1")).toEqual({ major: 22, minor: 16, patch: 0 });
     expect(parseSemver("invalid")).toBeNull();
   });
 
@@ -49,6 +51,9 @@ describe("runtime-guard", () => {
     expect(runtimeSatisfies(nodeOld)).toBe(false);
     expect(runtimeSatisfies(nodeTooOld)).toBe(false);
     expect(runtimeSatisfies(unknown)).toBe(false);
+    expect(isSupportedNodeVersion("22.16.0")).toBe(true);
+    expect(isSupportedNodeVersion("22.15.9")).toBe(false);
+    expect(isSupportedNodeVersion(null)).toBe(false);
   });
 
   it("throws via exit when runtime is too old", () => {
@@ -67,6 +72,7 @@ describe("runtime-guard", () => {
     };
     expect(() => assertSupportedRuntime(runtime, details)).toThrow("exit");
     expect(runtime.error).toHaveBeenCalledWith(expect.stringContaining("requires Node"));
+    expect(runtime.error).toHaveBeenCalledWith(expect.stringContaining("Detected: node 20.0.0"));
   });
 
   it("returns silently when runtime meets requirements", () => {
@@ -84,4 +90,25 @@ describe("runtime-guard", () => {
     expect(() => assertSupportedRuntime(runtime, details)).not.toThrow();
     expect(runtime.exit).not.toHaveBeenCalled();
   });
+
+  it("reports unknown runtimes with fallback labels", () => {
+    const runtime = {
+      log: vi.fn(),
+      error: vi.fn(),
+      exit: vi.fn(() => {
+        throw new Error("exit");
+      }),
+    };
+    const details: RuntimeDetails = {
+      kind: "unknown",
+      version: null,
+      execPath: null,
+      pathEnv: "(not set)",
+    };
+
+    expect(() => assertSupportedRuntime(runtime, details)).toThrow("exit");
+    expect(runtime.error).toHaveBeenCalledWith(
+      expect.stringContaining("Detected: unknown runtime (exec: unknown)."),
+    );
+  });
 });