Add a multi-language CRAP tool that writes .metrics/crap.edn for uml-viewer.

Score Clojure, Java, Go, TypeScript, Rust, and Python with each language's complexity rules and coverage report.

tests/test_typescript.py

@@ -0,0 +1,53 @@
+from crapper.languages.typescript import functions_in_source
+
+
+def test_function_class_method_and_arrow_are_separate_entries():
+    source = """
+export function choose(x: number): number {
+  if (x > 0 && x < 10) return 1;
+  for (let i = 0; i < x; i++) {
+    if (i === 2) return i;
+  }
+  try {
+    return x;
+  } catch (e) {
+    return 0;
+  }
+  return x > 0 ? 1 : 0;
+}
+
+export class Box {
+  open(flag?: boolean): number {
+    return flag ? 1 : 0;
+  }
+}
+
+const arrow = (n: number) => (n > 0 ? n : 0);
+
+function outer() {
+  function inner(n: number) {
+    if (n) return 1;
+    return 0;
+  }
+  return inner(1);
+}
+"""
+    functions = functions_in_source(source, "src/demo/box.ts", "/proj")
+    assert [(fn.namespace, fn.name, fn.complexity) for fn in functions] == [
+        ("demo.box", "choose", 7),
+        ("demo.box.Box", "open", 2),
+        ("demo.box", "arrow", 2),
+        ("demo.box", "outer", 2),
+    ]
+
+
+def test_tsx_counts_jsx_logic():
+    source = """
+export function View(ok: boolean, ready: boolean) {
+  return ok && ready ? 1 : 0;
+}
+"""
+    functions = functions_in_source(source, "src/ui/view.tsx", "/proj")
+    assert [(fn.namespace, fn.name, fn.complexity) for fn in functions] == [
+        ("ui.view", "View", 3)
+    ]