Adds 'dead_under_no_raise.py' to the bindings test suite, capturing the
three CPython patterns where bindings legitimately have no CFG node
because the surrounding code is unreachable under the 'no expressions
raise' abstraction:
1. Statements after a 'try: return X; except: pass' block.
2. The 'else:' clause of a try whose body always raises.
3. Cache-lookup pattern 'try: return cache[k]; except: pass' followed
by computation and store.
These bindings intentionally carry no 'cfgdefines=' annotations. If
raise modelling is later added to the CFG, the BindingsTest will surface
the new CFG nodes as unexpected results and this file will need to be
revisited.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds CFG coverage for the binding 'Name's introduced by PEP 695
type-parameter syntax on functions, classes, and 'type' aliases:
def func[T](...): ...
class Box[T]: ...
def multi[T: int, *Ts, **P](...): ...
type Alias[T] = ...
For each parametrised AST node, the type-parameter names (and, for
'type' aliases, the alias name itself) are added as children of the
enclosing CFG node so that 'Name.defines(v)' has a corresponding
position. Bounds and defaults are intentionally not wired (they have
no SSA-relevant semantics for our purposes).
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds `ImportStmt` and `ImportStarStmt` wrappers in `AstNodeImpl.qll`.
For each `Alias` in an import statement, both the value (module/member
expression) and the bound `asname` Name become children of the CFG node
for the import statement, in evaluation order.
Without this, every `Name` introduced by `import` / `from .. import ..`
lacked a CFG node, even though `Name.defines(v)` returns true for it on
the AST side. This was the highest-volume gap: 20,332 missing import
aliases across CPython.
Removes the corresponding MISSING: annotations from imports.py.
Verified: all 24 ControlFlow/evaluation-order tests still pass.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Implements `AstSig::Parameter` and `callableGetParameter(c, i)` in
`AstNodeImpl.qll`, following the C# template
(`csharp/.../ControlFlowGraph.qll:147-156`) rather than Java's
`Parameter() { none() }`.
Each Python parameter (positional, *args, keyword-only, **kwargs) now
becomes a CFG node at a stable position in the enclosing callable's
entry sequence. Defaults still evaluate at function-definition time
via `FunctionDefExpr.getDefault` / `LambdaExpr.getDefault`, so
`Parameter::getDefaultValue()` returns `none()` (the shared CFG
library calls this to model the missing-argument fallback, which
Python does not surface at the CFG level).
The bindings test now exercises parameters (the `py_expr_contexts(_, 4, ...)`
exclusion has been removed). A new `parameters.py` test case covers
positional, defaulted, vararg, kwarg, keyword-only, kitchen-sink,
method (self/cls), lambda, and PEP 570 positional-only parameters.
Several other test files were updated to annotate parameters that the
test had previously hidden (synthetic `.0` comprehension parameter,
method `self`, decorator `f`, etc.).
Verified:
- All 24 ControlFlow/evaluation-order tests still pass.
- CFG consistency query (`python/ql/consistency-queries/CfgConsistency.ql`)
shows zero violations on CPython.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds an `AnnAssignStmt` wrapper in `AstNodeImpl.qll` so that PEP 526
annotated assignments (`x: int = 1`, `x: int`) participate in the
control flow graph. Evaluation order follows CPython: annotation,
optional value, target binding.
Without this, `x: int = 1` had no CFG node for `x` even though
`Name.defines(v)` returns true for it on the AST side. SSA built on
the new CFG would therefore miss every annotated-assignment write.
Removes the corresponding MISSING: annotations from the CFG-binding
gap test:
- annassign.py — all four cases now green.
- match_pattern.py — class-body annotated fields (`x: int`, `y: int`).
- type_params.py — `item: T` inside class.
Verified: all 24 ControlFlow/evaluation-order tests still pass.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Adds inline-expectation tests for the new shared CFG implementation in
python/ql/lib/semmle/python/controlflow/internal/AstNodeImpl.qll,
covering every Python binding construct that introduces a variable.
The test files use MISSING: annotations to record bindings whose
defining Name AST node is *not* currently reachable from the new CFG.
These are the 'red' half of red-green commit pairs: subsequent commits
will extend AstNodeImpl to cover each construct and remove the
corresponding MISSING: marker.
Confirmed-broken categories:
- Import aliases (from x import a)
- Annotated assignment (x: int = 1)
- Exception handler (except E as e)
- Match patterns (case x, case [a,b], case ... as v)
- PEP 695 type params (def f[T], class C[T])
Confirmed-working (no MISSING:):
- Compound targets, with-as, comprehensions, decorated def/class,
walrus, starred.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
