fix(viewer): pretty print fallback tokenizer quand highlight.js ne produit aucun token (txt/log/plaintext) (#89)

tests/frontend/pretty.test.mjs

@@ -40,8 +40,11 @@ function escapeHtml(s) {
 
 const sandbox = { escapeHtml };
 vm.createContext(sandbox);
-vm.runInContext(`${extractFn("detectPrettyLang")}\n${extractFn("buildPrettyHtml")}\nglobalThis.detectPrettyLang = detectPrettyLang; globalThis.buildPrettyHtml = buildPrettyHtml;`, sandbox);
-const { detectPrettyLang, buildPrettyHtml } = sandbox;
+vm.runInContext(
+  `${extractFn("detectPrettyLang")}\n${extractFn("buildPrettyHtml")}\n${src.slice(src.indexOf("const PP_TOKEN_RE"), src.indexOf("function applyPrettyHighlight"))}\nglobalThis.fallbackTokenize = fallbackTokenize;`,
+  sandbox,
+);
+const { detectPrettyLang, buildPrettyHtml, fallbackTokenize } = sandbox;
 
 console.log("Testing detectPrettyLang...");
 assert.equal(detectPrettyLang({ is_json: true }), "json");
@@ -68,4 +71,17 @@ const xss = buildPrettyHtml({ extension: ".py", html: "" }, 'print("<script>aler
 assert.ok(!xss.includes("<script>"), "no raw script tag injected");
 assert.ok(xss.includes("&lt;script&gt;"), "script tag escaped");
 
+console.log("Testing fallbackTokenize (log levels, strings, comments)...");
+const fb = fallbackTokenize('2026-09-14 ERROR failed to open "/var/db"\n# note simple\nvalue=42');
+assert.ok(fb.includes("pp-err"), "ERROR level colored");
+assert.ok(fb.includes("hljs-string"), "quoted string colored");
+assert.ok(fb.includes("hljs-comment"), "comment colored");
+assert.ok(fb.includes("hljs-number"), "number colored");
+assert.ok(fb.includes("hljs-attr"), "key= colored");
+
+console.log("Testing fallbackTokenize (no html injection)...");
+const fbXss = fallbackTokenize('bad <img src=x onerror="alert(1)">');
+assert.ok(!/<img/.test(fbXss), "no raw img tag");
+assert.ok(fbXss.includes("&lt;img"), "img escaped");
+
 console.log("✅ All pretty-print tests passed successfully!");