Refactor markdown render (#32728)

Follow up recent render system refactoring PRs (split test code), and
fine tune the math render (added some new cases)

modules/markup/markdown/markdown_math_test.go

@@ -0,0 +1,163 @@
+// Copyright 2024 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package markdown
+
+import (
+	"strings"
+	"testing"
+
+	"code.gitea.io/gitea/modules/markup"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestMathRender(t *testing.T) {
+	const nl = "\n"
+	testcases := []struct {
+		testcase string
+		expected string
+	}{
+		{
+			"$a$",
+			`<p><code class="language-math is-loading">a</code></p>` + nl,
+		},
+		{
+			"$ a $",
+			`<p><code class="language-math is-loading">a</code></p>` + nl,
+		},
+		{
+			"$a$ $b$",
+			`<p><code class="language-math is-loading">a</code> <code class="language-math is-loading">b</code></p>` + nl,
+		},
+		{
+			`\(a\) \(b\)`,
+			`<p><code class="language-math is-loading">a</code> <code class="language-math is-loading">b</code></p>` + nl,
+		},
+		{
+			`$a$.`,
+			`<p><code class="language-math is-loading">a</code>.</p>` + nl,
+		},
+		{
+			`.$a$`,
+			`<p>.$a$</p>` + nl,
+		},
+		{
+			`$a a$b b$`,
+			`<p>$a a$b b$</p>` + nl,
+		},
+		{
+			`a a$b b`,
+			`<p>a a$b b</p>` + nl,
+		},
+		{
+			`a$b $a a$b b$`,
+			`<p>a$b $a a$b b$</p>` + nl,
+		},
+		{
+			"a$x$",
+			`<p>a$x$</p>` + nl,
+		},
+		{
+			"$x$a",
+			`<p>$x$a</p>` + nl,
+		},
+		{
+			"$a$ ($b$) [$c$] {$d$}",
+			`<p><code class="language-math is-loading">a</code> (<code class="language-math is-loading">b</code>) [$c$] {$d$}</p>` + nl,
+		},
+		{
+			"$$a$$",
+			`<pre class="code-block is-loading"><code class="chroma language-math display">a</code></pre>` + nl,
+		},
+		{
+			"$$a$$ test",
+			`<p><code class="language-math display is-loading">a</code> test</p>` + nl,
+		},
+		{
+			"test $$a$$",
+			`<p>test <code class="language-math display is-loading">a</code></p>` + nl,
+		},
+		{
+			"foo $x=\\$$ bar",
+			`<p>foo <code class="language-math is-loading">x=\$</code> bar</p>` + nl,
+		},
+	}
+
+	for _, test := range testcases {
+		t.Run(test.testcase, func(t *testing.T) {
+			res, err := RenderString(markup.NewTestRenderContext(), test.testcase)
+			assert.NoError(t, err)
+			assert.Equal(t, test.expected, string(res))
+		})
+	}
+}
+
+func TestMathRenderBlockIndent(t *testing.T) {
+	testcases := []struct {
+		name     string
+		testcase string
+		expected string
+	}{
+		{
+			"indent-0",
+			`
+\[
+\alpha
+\]
+`,
+			`<pre class="code-block is-loading"><code class="chroma language-math display">
+\alpha
+</code></pre>
+`,
+		},
+		{
+			"indent-1",
+			`
+ \[
+ \alpha
+ \]
+`,
+			`<pre class="code-block is-loading"><code class="chroma language-math display">
+\alpha
+</code></pre>
+`,
+		},
+		{
+			"indent-2",
+			`
+  \[
+  \alpha
+  \]
+`,
+			`<pre class="code-block is-loading"><code class="chroma language-math display">
+\alpha
+</code></pre>
+`,
+		},
+		{
+			"indent-0-oneline",
+			`$$ x $$
+foo`,
+			`<pre class="code-block is-loading"><code class="chroma language-math display"> x </code></pre>
+<p>foo</p>
+`,
+		},
+		{
+			"indent-3-oneline",
+			`   $$ x $$<SPACE>
+foo`,
+			`<pre class="code-block is-loading"><code class="chroma language-math display"> x </code></pre>
+<p>foo</p>
+`,
+		},
+	}
+
+	for _, test := range testcases {
+		t.Run(test.name, func(t *testing.T) {
+			res, err := RenderString(markup.NewTestRenderContext(), strings.ReplaceAll(test.testcase, "<SPACE>", " "))
+			assert.NoError(t, err)
+			assert.Equal(t, test.expected, string(res), "unexpected result for test case:\n%s", test.testcase)
+		})
+	}
+}