From b50b83fbd827e9307a3a2041be48e11762482876 Mon Sep 17 00:00:00 2001
From: Harry Yep <git@hode.co.uk>
Date: Tue, 30 Jun 2026 17:38:44 +0800
Subject: [PATCH] test(desktop): add math-delimiter fixtures for the
 react-streamdown preprocess swap

lock the four behaviors the built-in normalizeMathDelimiters/escapeCurrencyDollars introduce over the deleted custom helpers: $$<digit>$$ display math stays intact, double-backslash brackets and [/math]/[/inline] tag pairs rewrite to dollar delimiters, and currency dollars in prose are escaped. the existing preprocessMarkdown suite had no math cases.
---
 .../assistant-ui/markdown-text.test.ts        | 25 +++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/apps/desktop/src/components/assistant-ui/markdown-text.test.ts b/apps/desktop/src/components/assistant-ui/markdown-text.test.ts
index b3ea416d0664..748bef09e288 100644
--- a/apps/desktop/src/components/assistant-ui/markdown-text.test.ts
+++ b/apps/desktop/src/components/assistant-ui/markdown-text.test.ts
@@ -210,4 +210,29 @@ describe('preprocessMarkdown', () => {
 
     expect(() => preprocessMarkdown(input)).not.toThrow()
   })
+
+  it('keeps $$<digit>$$ display math intact instead of escaping it as currency', () => {
+    const output = preprocessMarkdown('$$5x = 10$$')
+
+    expect(output).toContain('$$5x = 10$$')
+    expect(output).not.toContain('\\$')
+  })
+
+  it('rewrites double-backslash bracket math to dollar delimiters', () => {
+    const output = preprocessMarkdown('\\\\(x^2\\\\)')
+
+    expect(output).toContain('$x^2$')
+  })
+
+  it('rewrites [/math] and [/inline] tag pairs to dollar delimiters', () => {
+    expect(preprocessMarkdown('[/math]a+b[/math]')).toContain('$$a+b$$')
+    expect(preprocessMarkdown('[/inline]x[/inline]')).toContain('$x$')
+  })
+
+  it('escapes currency dollars in prose so they are not parsed as math', () => {
+    const output = preprocessMarkdown('$5 and $10')
+
+    expect(output).toContain('\\$5')
+    expect(output).toContain('\\$10')
+  })
 })