Squashed 'third_party/pi/' content from commit d981de122

git-subtree-dir: third_party/pi
git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

packages/coding-agent/test/syntax-highlight.test.ts

@@ -0,0 +1,113 @@
+import { resetCapabilitiesCache, setCapabilities } from "@earendil-works/pi-tui";
+import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { highlightCode, initTheme } from "../src/modes/interactive/theme/theme.ts";
+import {
+	highlight,
+	loadAllHighlightLanguages,
+	renderHighlightedHtml,
+	supportsLanguage,
+} from "../src/utils/syntax-highlight.ts";
+
+const eagerLanguages = [
+	"python",
+	"java",
+	"go",
+	"javascript",
+	"cpp",
+	"typescript",
+	"php",
+	"ruby",
+	"c",
+	"csharp",
+	"nix",
+	"bash",
+	"rust",
+	"scala",
+	"kotlin",
+	"swift",
+	"dart",
+	"groovy",
+	"perl",
+	"lua",
+];
+const eagerLanguagesLoadedAtStartup = eagerLanguages.every(supportsLanguage);
+const uncommonLanguageLoadedAtStartup = supportsLanguage("ada");
+
+describe("syntax highlight renderer", () => {
+	it("loads the twenty most common languages at startup and defers the rest", async () => {
+		expect(eagerLanguagesLoadedAtStartup).toBe(true);
+		expect(uncommonLanguageLoadedAtStartup).toBe(false);
+		await loadAllHighlightLanguages();
+		expect(supportsLanguage("ada")).toBe(true);
+	});
+
+	it("renders highlighted spans with the provided theme", () => {
+		const rendered = renderHighlightedHtml('<span class="hljs-keyword">const</span> value', {
+			keyword: (text) => `[keyword:${text}]`,
+		});
+		expect(rendered).toBe("[keyword:const] value");
+	});
+
+	it("decodes HTML entities emitted by highlight.js", () => {
+		const rendered = renderHighlightedHtml("&lt;tag attr=&quot;value&quot;&gt;&amp;#x41;&#65;&lt;/tag&gt;");
+		expect(rendered).toBe('<tag attr="value">&#x41;A</tag>');
+	});
+
+	it("inherits parent formatting for unmapped nested scopes", () => {
+		const interpolation = "$" + "{x}";
+		const rendered = renderHighlightedHtml(
+			`<span class="hljs-string">a<span class="hljs-subst">${interpolation}</span>b</span>`,
+			{
+				string: (text) => `[string:${text}]`,
+			},
+		);
+		expect(rendered).toBe(`[string:a][string:${interpolation}][string:b]`);
+	});
+
+	it("keeps parent formatting across unscoped nested spans", () => {
+		const rendered = renderHighlightedHtml('<span class="hljs-string">a<span class="language-xml">b</span>c</span>', {
+			string: (text) => `[string:${text}]`,
+		});
+		expect(rendered).toBe("[string:a][string:b][string:c]");
+	});
+
+	it("highlights code through highlight.js", () => {
+		expect(supportsLanguage("typescript")).toBe(true);
+		const rendered = highlight("const value = 1", {
+			language: "typescript",
+			ignoreIllegals: true,
+			theme: {
+				keyword: (text) => `[keyword:${text}]`,
+				number: (text) => `[number:${text}]`,
+			},
+		});
+		expect(rendered).toContain("[keyword:const]");
+		expect(rendered).toContain("[number:1]");
+	});
+});
+
+describe("theme syntax highlighting", () => {
+	beforeEach(() => {
+		setCapabilities({ images: null, trueColor: true, hyperlinks: false });
+		initTheme("dark");
+	});
+
+	afterEach(() => {
+		resetCapabilitiesCache();
+	});
+
+	it("colors diff additions and deletions in fenced diff blocks", () => {
+		const lines = highlightCode("-old\n+new\n", "diff");
+
+		expect(lines[0]).toBe("\x1b[38;2;204;102;102m-old\x1b[39m");
+		expect(lines[1]).toBe("\x1b[38;2;181;189;104m+new\x1b[39m");
+	});
+
+	it("keeps cli-highlight default styled scopes mapped to theme styles", () => {
+		expect(highlightCode("const re = /foo+/gi;", "javascript")[0]).toContain(
+			"\x1b[38;2;206;145;120m/foo+/gi\x1b[39m",
+		);
+		expect(highlightCode("@decorator", "python")[0]).toBe("\x1b[38;2;128;128;128m@decorator\x1b[39m");
+		expect(highlightCode("<div></div>", "html")[0]).toContain("\x1b[38;2;86;156;214mdiv\x1b[39m");
+	});
+});