"""Regression tests for the bridge.
Covers:
- index.html declares the static prefers-color-scheme media variants (light + dark).
- index.html declares a single `id="hermes-theme-color"` meta tag for runtime updates.
- Inline pre-paint script reads localStorage `hermes-theme` and seeds the meta tag
before any external JS loads (no flash of wrong colour for native chrome).
- boot.js defines `_syncThemeColorMeta()` and calls it from `_setResolvedTheme()`
(covering both prism-loaded and prism-absent paths) and from `_applySkin()`.
- The helper reads `getComputedStyle(html).getPropertyValue('--bg')`, which means
every skin (Default, Sienna, Sisyphus, Charizard, etc.) reaches the meta tag.
- Both the pre-paint script and boot sync update all theme-color tags and remove
stale media attributes so OS light/dark preference cannot override the user theme.
This bridge is the source of truth that native WKWebView wrappers
(hermes-webui/hermes-swift-mac) read instead of pixel-sampling the page —
overlay-resistant (modals/lightboxes don't poison it) and IPC-free.
"""
from pathlib import Path
ROOT = Path(__file__).resolve().parent.parent
INDEX = ROOT / "static" / "index.html"
BOOT = ROOT / "static" / "boot.js"
STYLE = ROOT / "static" / "style.css"
class TestIndexHtmlMetaTags:
def test_static_prefers_color_scheme_variants_present(self):
"""Two static tags with media queries cover the
pre-load case for browsers that use the OS color scheme as a hint.
"""
src = INDEX.read_text(encoding="utf-8")
assert 'name="theme-color"' in src
assert 'media="(prefers-color-scheme: light)"' in src
assert 'media="(prefers-color-scheme: dark)"' in src
def test_runtime_theme_color_meta_has_stable_id(self):
"""A third theme-color meta tag (no media query) carries id="hermes-theme-color"
so boot.js can update it on theme/skin change. The id is the contract the
Mac Swift app reads via `document.getElementById('hermes-theme-color')`.
"""
src = INDEX.read_text(encoding="utf-8")
assert 'id="hermes-theme-color"' in src
# Must be on a meta tag (not some other element)
assert ' seeds all theme-color tags from localStorage
before any external JS loads. This prevents a single-frame flash of the
OS-default theme-color when the user has explicitly chosen the opposite,
and prevents media-query fallbacks from overriding the runtime tag.
"""
src = INDEX.read_text(encoding="utf-8")
assert "hermes-theme" in src
# The seeder must read from the same localStorage key the theme bootstrap uses.
assert "localStorage.getItem('hermes-theme')" in src
# It must update every theme-color tag and neutralize stale light/dark media hints.
assert "querySelectorAll('meta[name=\"theme-color\"]')" in src
assert "setAttribute('content'" in src or 'setAttribute("content"' in src
assert "removeAttribute('media')" in src
class TestBootJsThemeColorSync:
def test_sync_helper_defined(self):
src = BOOT.read_text(encoding="utf-8")
assert "function _syncThemeColorMeta()" in src
def test_sync_helper_reads_computed_bg_var(self):
"""The helper must read the computed --bg CSS custom property so each skin's
background reaches the meta tag (Sienna gets terracotta, Sisyphus gets purple,
etc.).
"""
src = BOOT.read_text(encoding="utf-8")
# The helper reads getComputedStyle on documentElement and extracts --bg.
assert "getComputedStyle(document.documentElement).getPropertyValue('--bg')" in src
def test_sync_helper_updates_all_theme_color_tags(self):
"""The helper must update the canonical id tag and the static fallback tags.
Desktop/native chrome can prefer a matching media tag over the id tag; if
stale media variants remain light while the app is dark, the title bar goes beige.
Civilization trembles, but mostly the window looks wrong.
"""
src = BOOT.read_text(encoding="utf-8")
assert "getElementById('hermes-theme-color')" in src
assert "querySelectorAll('meta[name=\"theme-color\"]')" in src
assert "setAttribute('content',bg)" in src
assert "removeAttribute('media')" in src
def test_set_resolved_theme_calls_sync_in_both_branches(self):
"""_setResolvedTheme has two exit paths:
1. Early return when the Prism stylesheet is absent (onboarding pages,
error pages, etc.).
2. Normal completion after possibly toggling the Prism stylesheet href.
Both paths must update the meta tag — otherwise the Mac chrome would lag
the page on those paths.
"""
src = BOOT.read_text(encoding="utf-8")
# Path 1 — the early return must call the sync first.
assert "if(!link){ _syncThemeColorMeta(); return; }" in src
# Path 2 — the trailing call must follow the link-href update.
assert (
"if(link.href!==want){ link.integrity=''; link.href=want; }\n"
" _syncThemeColorMeta();"
) in src
def test_apply_skin_calls_sync(self):
"""Switching skin (Default → Sienna → Sisyphus, etc.) recomputes --bg and
must update the meta tag so the Mac chrome flips with the page.
"""
src = BOOT.read_text(encoding="utf-8")
# The end of _applySkin must call the sync.
# We assert the literal anchor block from the recent edit so any drift
# in surrounding code triggers a clear test failure.
anchor = (
"function _applySkin(name){\n"
" const key=(name||'default').toLowerCase();\n"
" if(key==='default') delete document.documentElement.dataset.skin;\n"
" else document.documentElement.dataset.skin=key;\n"
" _syncThemeColorMeta();\n"
"}"
)
assert anchor in src
class TestStyleCssBgVarPresent:
"""The bridge depends on every theme/skin defining the --bg CSS variable.
These are the canonical locations as of v0.51.x — if any are missing or
renamed the meta-tag reader returns empty and the Mac chrome reverts to the
static prefers-color-scheme defaults.
"""
def test_root_light_defines_bg(self):
src = STYLE.read_text(encoding="utf-8")
# :root (light default) at the top of the file defines --bg.
assert "--bg:#FEFCF7" in src or "--bg: #FEFCF7" in src
def test_root_dark_defines_bg(self):
src = STYLE.read_text(encoding="utf-8")
assert "--bg:#0D0D1A" in src or "--bg: #0D0D1A" in src