tests/perf_bench: Add string/qstr/map tests.

These tests are designed to measure changes in performance relating to:
 - string interning / searching for existing strings
 - map lookup
 - string operations
 - string hashing

This work was funded through GitHub Sponsors.

Signed-off-by: Jim Mussared <jim.mussared@gmail.com>

tests/perf_bench/core_str.py

@@ -0,0 +1,65 @@
+# This tests string handling operations
+
+ZEN = """
+The Zen of Python
+Beautiful is better than ugly.
+Explicit is better than implicit.
+Simple is better than complex.
+Complex is better than complicated.
+Flat is better than nested.
+Sparse is better than dense.
+Readability counts.
+Special cases aren't special enough to break the rules.
+Although practicality beats purity.
+Errors should never pass silently.
+Unless explicitly silenced.
+In the face of ambiguity, refuse the temptation to guess.
+There should be one-- and preferably only one --obvious way to do it.
+Although that way may not be obvious at first unless you're Dutch.
+Now is better than never.
+Although never is often better than *right* now.
+If the implementation is hard to explain, it's a bad idea.
+If the implementation is easy to explain, it may be a good idea.
+Namespaces are one honking great idea -- let's do more of those!
+"""
+
+
+def test(niter):
+    counts = {}
+    for _ in range(niter):
+        x = ZEN.replace("\n", " ").split(" ")
+        y = " ".join(x)
+        for i in range(50):
+            a = ZEN[i : i * 2]
+            b = a + "hello world"
+        for c in ZEN:
+            i = ord(c)
+            c = chr(i)
+    return (x[0], a)
+
+
+###########################################################################
+# Benchmark interface
+
+bm_params = {
+    (32, 10): (2,),
+    (50, 10): (3,),
+    (100, 10): (6,),
+    (500, 10): (30,),
+    (1000, 10): (60,),
+    (5000, 10): (300,),
+}
+
+
+def bm_setup(params):
+    (niter,) = params
+    state = None
+
+    def run():
+        nonlocal state
+        state = test(niter)
+
+    def result():
+        return niter, state
+
+    return run, result