measurestack: Add a `dbg_sort` toggle

1 files changed, 43 insertions, 3 deletions

diff --git a/build-aux/measurestack/analyze.py b/build-aux/measurestack/analyze.py
index 86c51f2..3601707 100644
--- a/build-aux/measurestack/analyze.py
+++ b/build-aux/measurestack/analyze.py
@@ -3,6 +3,7 @@
 # Copyright (C) 2024-2025  Luke T. Shumaker <lukeshu@lukeshu.com>
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
+import random
 import re
 import sys
 import typing
@@ -13,6 +14,8 @@ from . import vcg
 dbg_dumpgraph = False
 # Whether to print "//dbg-nstatic:" lines that trace nstatic() execution
 dbg_nstatic = False
+# Whether to sort things for consistently-ordered execution, or shuffle things to detect bugs
+dbg_sort: typing.Literal["unsorted", "sorted", "shuffled"] = "unsorted"
 
 # pylint: disable=unused-variable
 __all__ = [
@@ -20,6 +23,7 @@ __all__ = [
     "QName",
     "UsageKind",
     "Node",
+    "maybe_sorted",
     "AnalyzeResultVal",
     "AnalyzeResultGroup",
     "AnalyzeResult",
@@ -306,6 +310,39 @@ class _Graph:
         return self._resolve_cache[funcname]
 
 
+if typing.TYPE_CHECKING:
+    from _typeshed import SupportsRichComparisonT as _T_sortable
+
+_T = typing.TypeVar("_T")
+
+
+@typing.overload
+def maybe_sorted(
+    unsorted: typing.Iterable["_T_sortable"], /, *, key: None = None
+) -> typing.Iterable["_T_sortable"]: ...
+@typing.overload
+def maybe_sorted(
+    unsorted: typing.Iterable[_T], /, *, key: typing.Callable[[_T], "_T_sortable"]
+) -> typing.Iterable[_T]: ...
+
+
+def maybe_sorted(
+    unsorted: typing.Iterable[_T],
+    /,
+    *,
+    key: typing.Callable[[_T], "_T_sortable"] | None = None,
+) -> typing.Iterable[_T]:
+    match dbg_sort:
+        case "unsorted":
+            return unsorted
+        case "sorted":
+            return sorted(unsorted, key=key)  # type: ignore
+        case "shuffled":
+            ret = [*unsorted]
+            random.shuffle(ret)
+            return ret
+
+
 def _make_graph(
     ci_fnames: typing.Collection[str],
     app: Application,
@@ -368,7 +405,7 @@ def _make_graph(
                     raise ValueError(f"unknown caller: {caller}")
                 if callee == QName("__indirect_call"):
                     callees, missing_ok = app.indirect_callees(elem)
-                    for callee in callees:
+                    for callee in maybe_sorted(callees):
                         if callee not in graph[caller].calls:
                             graph[caller].calls[callee] = missing_ok
                 else:
@@ -376,12 +413,15 @@ def _make_graph(
             case _:
                 raise ValueError(f"unknown elem type {elem.typ!r}")
 
-    for ci_fname in ci_fnames:
+    for ci_fname in maybe_sorted(ci_fnames):
         with open(ci_fname, "r", encoding="utf-8") as fh:
             for elem in vcg.parse_vcg(fh):
                 handle_elem(elem)
 
-    for node in app.extra_nodes():
+    def sort_key(node: Node) -> QName:
+        return node.funcname
+
+    for node in maybe_sorted(app.extra_nodes(), key=sort_key):
         if node.funcname in graph:
             raise ValueError(f"duplicate node {node.funcname}")
         graph[node.funcname] = node