BLD: Ensure pympler is present

asv/benchmark.py

@@ -706,20 +706,25 @@ def __init__(self, name, func, attr_sources):
 
     def run(self, *param):
         if ON_PYPY:
-            raise UserWarning("asizeof doesn't work on pypy")
+            raise NotImplementedError("asizeof doesn't work on pypy")
             return
+
         try:
             from pympler.asizeof import asizeof
         except ImportError:
-            raise UserWarning("pympler not found, memory benchmarks shall fail")
+            try:
+                subprocess.check_output(["python", "-mpip", "install", "pympler==0.9"])
+            except subprocess.CalledProcessError as e:
+                raise NotImplementedError(f"Failed to install pympler: {e.output.decode()}")
+            raise NotImplementedError("pympler not found, installed successfully")
+
         obj = self.func(*param)
 
         sizeof2 = asizeof([obj, obj])
         sizeofcopy = asizeof([obj, copy.copy(obj)])
 
         return sizeofcopy - sizeof2
 
-
 class PeakMemBenchmark(Benchmark):
     """
     Represents a single benchmark for tracking the peak memory consumption

pyproject.toml

@@ -46,6 +46,7 @@ test = [
     "selenium",
     "pytest-rerunfailures",
     "python-hglib",
+    "pympler; platform_python_implementation != \"PyPy\"",
 ]
 doc = [
     "sphinx",

requirements-dev.txt

@@ -18,3 +18,4 @@ python-hglib
 flake8
 isort>= 5.11.5
 json5
+pympler; platform_python_implementation != "PyPy"