fix(browser): ignore duplicate frame navigations and read block-form source map directives (#546)

src/domain/javascriptStaticAnalysisSourceMaps.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+
+import { analyzeJavaScriptStaticSource } from "./javascriptStaticAnalysis.js";
+
+const sourceMapUrls = (source: string): readonly string[] =>
+  analyzeJavaScriptStaticSource(source).source_map_urls.map(
+    ({ declared_url: declaredUrl }) => declaredUrl,
+  );
+
+describe("source map directives", () => {
+  it.each([
+    ["line comment", "//# sourceMappingURL=app.js.map", "app.js.map"],
+    ["legacy line comment", "//@ sourceMappingURL=app.js.map", "app.js.map"],
+    // Minifiers commonly emit the block form; it previously matched nothing.
+    ["block comment", "/*# sourceMappingURL=app.js.map */", "app.js.map"],
+    [
+      "block comment after code",
+      "code();\n/*# sourceMappingURL=vendor.abc.map */",
+      "vendor.abc.map",
+    ],
+  ])("reads the %s form", (_label, source, expected) => {
+    expect(sourceMapUrls(source)).toEqual([expected]);
+  });
+
+  it("keeps the comment terminator out of the declared url", () => {
+    expect(sourceMapUrls("/*# sourceMappingURL=app.js.map */")).toEqual([
+      "app.js.map",
+    ]);
+  });
+
+  it("retains every directive in a source", () => {
+    expect(
+      sourceMapUrls(
+        "//# sourceMappingURL=first.map\n/*# sourceMappingURL=second.map */",
+      ),
+    ).toEqual(["first.map", "second.map"]);
+  });
+
+  it("reports nothing when no directive is present", () => {
+    expect(sourceMapUrls("const value = 1;")).toEqual([]);
+  });
+});