Second batch of test reblessings, capturing changes in result content
(not just toString labels):
- Framework taint/concept tests (fastapi, sqlalchemy, aiohttp, lxml,
stdlib, django-orm): mostly gained MISSING-tainted annotations where
the new dataflow no longer reaches sinks. Some are real taint
regressions; left as documented failures for follow-up.
- Exception-handler tests (CWE-209-StackTraceExposure, EmptyExcept,
CatchingBaseException, IncorrectExceptOrder, FileNotAlwaysClosed,
FindSubclass/Find, Statements/exit/UseOfExit): the no-raise shared CFG
abstraction does not emit ExceptionSuccessor abrupt-completion edges
from arbitrary expressions, so except-handler bodies (and their
exception target Names) are statically dead. Tracked separately under
cfg-modelling-exceptions.
- Dataflow-path / control-flow node toString polish across the security
query suite (PathInjection, CodeInjection, UnsafeUnpacking,
UnsafeUsageOfClientSideEncryptionVersion, RequestWithoutValidation,
ReflectedXss, CallGraph): simple-leaf nodes now stringify as their
AST text instead of 'After X'.
- SSA / call-graph improvements (CmpTest, CallGraph/InlineCallGraphTest):
fewer SSA mismatches between new and old; two previously-MISSING tt=
annotations resolved.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
The new SSA's implicit entry-def predicate previously placed entries in
the variable's defining scope. For closure variables that's the outer
function, so inner functions had no entry def for the captured
variable — reads in the inner scope failed to resolve to any
definition.
Mirrors legacy ESSA's 'NonLocalVariable.getScopeEntryDefinition()':
place an implicit entry def at every reading scope's entry block,
independently of where the variable is *defined*. A closure variable
accessed in two nested functions and the outer one gets three entry
defs (one per reading scope).
Also makes 'ScopeEntryDefinition' extend 'EssaNodeDefinition' (matching
legacy ESSA), with 'getDefiningNode()' returning the scope's entry CFG
node. This requires extending the private 'writeDefNode' helper to
project i=-1 entries to bb.getNode(0).
Updates the new-vs-legacy comparison snapshot: closure-variable reads
('x:32:5'), nested global reads ('GLOBAL:52:1') now resolve. New
'def-only-new' entries appear for unbound names ('sum', 'open',
'compute') — the new SSA uniformly creates scope-entry defs for all
non-local reads, including those that legacy ESSA classifies as
builtin and excludes. This is a more uniform semantic and arguably
cleaner.
Updates the SsaTest 'some_undefined' annotation: previously documented
as a known limitation, now correctly resolves to a scope-entry def.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Phase 0.5 - Adapter API on top of the shared SSA:
Adds the legacy-ESSA-shaped class hierarchy that the dataflow library
consumes, layered on the shared 'Ssa::Make' instantiation:
* EssaDefinition / EssaNodeDefinition: the latter exposes
'getDefiningNode()' (the CFG node at the def's index in its BB)
and 'getVariable()' / 'getScope()'.
* AssignmentDefinition: matches Assign, AnnAssign with value,
AssignExpr and AugAssign target Names. Exposes 'getValue()'
pointing at the RHS' CFG node.
* ParameterDefinition: matches when the defining Name is in
parameter context.
* WithDefinition: matches 'with ... as x:' bindings.
* ScopeEntryDefinition: implicit entry defs at synthetic position
'-1' of the scope's entry basic block (non-local / global /
builtin / captured reads).
* PhiFunction (alias for PhiNode).
* EssaVariable adapter wrapping a 'Ssa::Definition' with 'getAUse()',
'getDefinition()', 'getAnUltimateDefinition()', and 'getName()'.
* AdjacentUses module with 'firstUse' and 'adjacentUseUse' predicates
bridging to 'Ssa::firstUse' / 'Ssa::adjacentUseUse'.
This is the minimum API the new dataflow's internals call into. The
richer legacy ESSA (refinement nodes, attribute refinements, edge
refinements) stays in 'semmle.python.essa.Essa' for legacy code.
Phase 0.6 - Comparison test:
Adds 'dataflow-new-ssa-vs-legacy/CmpTest.ql' that snapshots the
difference between definitions produced by new SSA vs legacy ESSA on
the same Python source. Baseline output records the current
'def-only-old' mismatches, grouped by category:
* function/class/global definitions with no in-scope read (intentional;
SSA is liveness-pruned)
* captured / closure variables (real gap in new SSA - no
closure-capture handling yet)
* module variables __name__ / __package__ / $ (legacy ESSA implicit
bindings)
* exception 'as' bindings (depend on raise modelling)
Zero 'def-only-new' mismatches: the new SSA never produces a spurious
definition compared to legacy ESSA on this corpus.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
