From c30a7965d4d5b446890beace9a14e0ce1397b90c Mon Sep 17 00:00:00 2001
From: Matthew Anderson <and3rn3t@icloud.com>
Date: Fri, 18 Sep 2026 23:51:00 -0500
Subject: [PATCH] test(web): make the ResizeObserver mock constructible under
 any vitest

Recharts calls `new ResizeObserver(...)`, and the mock was built with
`vi.fn().mockImplementation(...)`. Whether a vitest mock function can be used
as a constructor is an implementation detail, and it changed in vitest 5:
every Recharts-backed test fails there with "... is not a constructor",
10 of the 144 in this suite.

A plain class does the same job without depending on that detail. Verified
both ways: 144/144 on the pinned vitest 3.2.6, and 144/144 on vitest 5.0.1,
which is what Dependabot #15 proposes. That PR cannot go green without this.

Also stop the generated coverage/ directory leaking into lint and git. It was
in neither web/.gitignore nor the eslint ignorePatterns, so running
`vitest run --coverage` produced instrumented copies of the source that
eslint then reported errors on, and left them untracked in the working tree.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
---
 web/.eslintrc.cjs     |  2 +-
 web/.gitignore        |  1 +
 web/src/test/setup.js | 15 +++++++++------
 3 files changed, 11 insertions(+), 7 deletions(-)

diff --git a/web/.eslintrc.cjs b/web/.eslintrc.cjs
index a128a6c..770caf4 100644
--- a/web/.eslintrc.cjs
+++ b/web/.eslintrc.cjs
@@ -7,7 +7,7 @@ module.exports = {
     'plugin:react/jsx-runtime',
     'plugin:react-hooks/recommended',
   ],
-  ignorePatterns: ['dist', '.eslintrc.cjs'],
+  ignorePatterns: ['dist', 'coverage', '.eslintrc.cjs'],
   parserOptions: { ecmaVersion: 'latest', sourceType: 'module' },
   settings: { react: { version: '18.2' } },
   plugins: ['react-refresh'],
diff --git a/web/.gitignore b/web/.gitignore
index d600b6c..d700a72 100644
--- a/web/.gitignore
+++ b/web/.gitignore
@@ -10,6 +10,7 @@ lerna-debug.log*
 node_modules
 dist
 dist-ssr
+coverage
 *.local
 
 # Editor directories and files
diff --git a/web/src/test/setup.js b/web/src/test/setup.js
index ddbd467..2c2fabb 100644
--- a/web/src/test/setup.js
+++ b/web/src/test/setup.js
@@ -16,12 +16,15 @@ if (globalThis.__VITEST_SETUP_LOADED__) {
   // Extend Vitest's expect with accessibility matchers
   expect.extend({ toHaveNoViolations });
 
-  // Mock ResizeObserver (needed for Recharts)
-  globalThis.ResizeObserver = vi.fn().mockImplementation(() => ({
-    observe: vi.fn(),
-    unobserve: vi.fn(),
-    disconnect: vi.fn(),
-  }));
+  // Mock ResizeObserver (needed for Recharts). A plain class rather than
+  // vi.fn().mockImplementation(): Recharts calls `new ResizeObserver(...)`,
+  // and whether a mock function is constructible is a vitest implementation
+  // detail that changed in v5.
+  globalThis.ResizeObserver = class ResizeObserver {
+    observe() {}
+    unobserve() {}
+    disconnect() {}
+  };
 
   // Mock scrollIntoView (needed for Logs component)
   Element.prototype.scrollIntoView = vi.fn();