Merge pull request #111 from codellm-devkit/feat/vendor-scalpel-default-oracle

feat(dataflow): vendored typed_ast-free scalpel as the default L4 oracle

Author: rahlk

.claude/SCHEMA_DECISIONS.md

@@ -152,6 +152,17 @@ supported 3.9–3.13+ range; `compute_SSA`'s return contract is discovered from
 source (not a documented public API) — wrap it behind `ScalpelAliasOracle` to
 contain upstream drift.
 
+**Follow-up (2026-07-22): Scalpel vendored, now the default.** The Stage-0
+"dependency hygiene" concern proved fatal for a hard dependency: `python-scalpel`
+drags `typed_ast`, which has no wheel for Python 3.12+ and does not build from
+source there, so `pip install python-scalpel` fails on 3.12/3.13/3.14. Since
+`typed_ast` is imported only by `scalpel/typeinfer` (unused here), the 9-module
+`SSA`/`cfg`/`core` slice the oracle loads was **vendored** into
+`codeanalyzer/dataflow/scalpel/` (Apache-2.0, verbatim but for a `graphviz`-lazy
+patch). `ScalpelAliasOracle` is now the shipping default on all supported Python;
+`TypeBasedAliasOracle` is the runtime safety net only. See
+`docs/superpowers/specs/2026-07-22-vendored-scalpel-default-oracle-design.md`.
+
 ## Stage 5 — keystone conformance sweep (issue #98, schema_version 2.0.0)
 
 The stage-5 pre-release conformance check against the canonical schema-v2

CHANGELOG.md

@@ -7,6 +7,16 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- The Scalpel-backed L4 points-to oracle is now **vendored** (`typed_ast`-free)
+  and the default on all supported Python (3.9–3.14); `python-scalpel` is no
+  longer an optional dependency and the `[scalpel]` extra is removed. On Python
+  3.12+ (and anywhere the `[scalpel]` extra was not installed), L4
+  `prov:["points-to"]` data-dependence edges are now Scalpel-precise rather than
+  the coarser type-based over-approximation; the `prov:["ssa"]` set and the
+  `L3 ⊆ L4` monotonicity invariant are unchanged. Adds `astor` as a runtime
+  dependency.
+
 ## [1.0.3] - 2026-07-21
 
 ### Fixed

CLAUDE.md

@@ -122,10 +122,13 @@ declared callables by their `can://` tree id, imported/builtin targets by a
   (`codeanalyzer/dataflow/scalpel_oracle.py`) consumes `python-scalpel`'s **solved
   SSA + copy/const** state (it never forks the solver) as a copy-closure union-find
   over access paths, behind the frozen `may_alias(path_a, path_b) -> bool`
-  interface. `python-scalpel` is an **optional** dependency: if it is absent or a
-  build/query fails, the analyzer falls back to the total `TypeBasedAliasOracle`
-  (`alias.py`) and degrades, never raising. The type-based oracle is the sanctioned
-  fallback, not the shipping default.
+  interface. Scalpel is **vendored** (`codeanalyzer/dataflow/scalpel/`, a
+  `typed_ast`-free 9-module slice of `python-scalpel 1.0b0`, Apache-2.0) so it is
+  the **shipping default** L4 oracle on every supported Python — there is no
+  external `python-scalpel`/`typed_ast` dependency. `TypeBasedAliasOracle`
+  (`alias.py`) is retained only as the runtime safety net: on a per-callable
+  Scalpel build failure or a per-query unresolved access path, `may_alias`
+  degrades to it, never raising.
 - **CLI gating** (`codeanalyzer/__main__.py`): `-a` max is 4; `--graphs sdg`
   requires `-a 4` (a flag error below that); `cfg,dfg,pdg` require `-a 3`;
   `--graph-field-depth` (the `k_limit`) is valid at L3+.

NOTICE

@@ -16,3 +16,10 @@ Any other use of CodeQL, including its use on proprietary code or in closed-sour
 
 You can view the full CodeQL license at:
 https://github.com/github/codeql/blob/main/LICENSE
+
+--- Scalpel License Notice ---
+
+This project vendors a slice of Scalpel (python-scalpel), a product of SMAT-Lab,
+under codeanalyzer/dataflow/scalpel/. Scalpel is licensed under the Apache
+License 2.0. The full license text is included at
+codeanalyzer/dataflow/scalpel/LICENSE. Source: https://github.com/SMAT-Lab/Scalpel

README.md

@@ -104,12 +104,9 @@ For the optional **live Neo4j push** (`--emit neo4j --neo4j-uri …`), install t
 pip install 'codeanalyzer-python[neo4j]'
 ```
 
-For the **Scalpel-backed points-to oracle** at level 4, install the `scalpel` extra. It is optional:
-when it is absent, level 4 automatically falls back to the built-in type-based oracle.
-
-```sh
-pip install 'codeanalyzer-python[scalpel]'
-```
+The **Scalpel-backed points-to oracle** at level 4 is vendored and built in — no extra install
+required. If Scalpel cannot resolve a construct, level 4 automatically falls back to the built-in
+type-based oracle.
 
 ### Install via shell script
 
@@ -529,11 +526,12 @@ symbol-table signature by construction
 - **Points-to oracle (level 4):** the **Scalpel** may-alias oracle — `ScalpelAliasOracle`
   (`codeanalyzer/dataflow/scalpel_oracle.py`) — consumes Scalpel's SSA copy/const facts to answer
   `may_alias(path_a, path_b)`, adding the alias-aware DDG edges (`prov: ["points-to"]`) and the
-  interprocedural summaries. `python-scalpel` is an **optional dependency**
-  (`pip install 'codeanalyzer-python[scalpel]'`); when it is absent or cannot resolve a construct,
-  the analyzer automatically falls back to the built-in `TypeBasedAliasOracle` (Jedi-inferred types;
-  unknown types conservatively alias), keeping the `may_alias` interface total. Call dispatch comes
-  from the merged Jedi(+PyCG) call graph, treated as a frozen oracle.
+  interprocedural summaries. Scalpel is **vendored** — a `typed_ast`-free slice built into the
+  package under `codeanalyzer/dataflow/scalpel/` — so it is the **default** level-4 oracle with no
+  external dependency to install; the analyzer falls back to the built-in `TypeBasedAliasOracle`
+  (Jedi-inferred types; unknown types conservatively alias) only when Scalpel can't resolve a
+  construct or a per-callable build fails, keeping the `may_alias` interface total. Call dispatch
+  comes from the merged Jedi(+PyCG) call graph, treated as a frozen oracle.
 - **Summaries:** relational formal-in → formal-out flows composed bottom-up over the Tarjan SCC
   condensation of the call graph, a monotone fixpoint within SCCs; globals ride as extra formals,
   closure captures bind at definition sites.

codeanalyzer/dataflow/scalpel/LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (i) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.

codeanalyzer/dataflow/scalpel/README.md

@@ -0,0 +1,34 @@
+# Vendored Scalpel (typed_ast-free slice)
+
+Vendored from **[SMAT-Lab/Scalpel](https://github.com/SMAT-Lab/Scalpel)**,
+package `python-scalpel==1.0b0`, licensed **Apache-2.0** (see `LICENSE`).
+
+## Why vendored
+
+`python-scalpel` hard-depends on `typed_ast`, whose last release (1.5.5) has no
+wheel for Python 3.12+ and fails to build from source on modern compilers — so
+`pip install python-scalpel` fails on 3.12/3.13/3.14. `typed_ast` is imported by
+exactly one scalpel module, `typeinfer/analysers.py`, which codeanalyzer does not
+use. Vendoring the small slice the L4 may-alias oracle needs removes the
+`typed_ast` dependency and makes scalpel the default oracle on every supported
+Python.
+
+## What is vendored
+
+Exactly the 9-module closure that `scalpel.SSA.const` + `scalpel.cfg` load
+(verified via `sys.modules`; provably free of `typeinfer`/`typed_ast`):
+
+    __init__.py
+    SSA/__init__.py, SSA/const.py
+    cfg/__init__.py, cfg/builder.py, cfg/model.py
+    core/__init__.py, core/func_call_visitor.py, core/vars_visitor.py
+
+Copied verbatim except **one patch**: `cfg/model.py`'s top-level
+`import graphviz as gv` is guarded (`try/except ImportError: gv = None`) so the
+module imports without the `graphviz` package — the graphviz-using
+`build_visual()` methods are unused here.
+
+Runtime deps of this slice: `astor`, `networkx` (both core dependencies of
+codeanalyzer). `typed_ast` and `graphviz` are NOT required.
+
+To refresh: re-run the vendoring in `docs/superpowers/plans/2026-07-22-vendored-scalpel-default-oracle.md` Task 1.

codeanalyzer/dataflow/scalpel/SSA/__init__.py

@@ -0,0 +1,8 @@
+"""
+Static Single Assignment (SSA) is a technique of IR in the compiling thoery, it also shows great benefits to static anaysis tasks such as constant propagation, dead code elimination and etc.
+Constant propagation is also a matured technique in static anaysis. 
+It is the process of evaluating or recognizing the actual constant values or expressions at a particular program point. This is realized by utilizing control flow and data flow information. Determining the possible values for variables before runtime gives great benefits to software anaysis. 
+For instance, with constant value propagation, we can detect and remove dead code or perfrom type checking.
+In scalpel, we implement constant propagation along with the SSA for execution efficiency.
+"""
+__slots__ = ["const"]