Rust: Path resolution for static items

[hvitved]

This PR:

• Adds resolution for static items, similar to what we do for const items.
• Improves toString for static and const items.
• Skips statics and consts in the CFG.
• Add data flow (jump) steps for reads of/writes to statics and consts.

[Copilot]

Pull request overview

This PR extends the Rust CodeQL libraries to resolve static items (similar to existing const handling), improves string representations for const/static, excludes them from CFG construction, and adds dataflow “jump” steps to model reads/writes involving const/static items; accompanying library and extractor tests are updated/added accordingly.

Changes:

• Add static path resolution support and a public StaticAccess API, aligning behavior with const where appropriate.
• Update control-flow and dataflow modeling to handle const/static initialization/access patterns (including new dataflow steps).
• Add/expand Rust library tests for static/const access and update expected outputs impacted by the new toString/resolution behavior.

Show a summary per file

File	Description
rust/ql/test/TestUtils.qll	Adds a reusable helper predicate for locating line comments used by multiple inline-expectation tests.
rust/ql/test/library-tests/variables/variables.ql	Switches variable tests to use the shared comment helper from TestUtils.
rust/ql/test/library-tests/static_access/static_access.ql	New inline-expectations test query covering StaticAccess resolution (including shadowing).
rust/ql/test/library-tests/static_access/static_access.expected	Expected results for the new static_access library test.
rust/ql/test/library-tests/static_access/main.rs	New Rust test program exercising global/module/inner-block static accesses and shadowing.
rust/ql/test/library-tests/static_access/Cargo.lock	Lockfile for the new static_access test crate.
rust/ql/test/library-tests/path-resolution/path-resolution.expected	Updates expected path-resolution results to include const/static module cases and new item string forms.
rust/ql/test/library-tests/path-resolution/main.rs	Adds const_static module to exercise path resolution for const/static items and aliases.
rust/ql/test/library-tests/dataflow/local/DataFlowStep.ql	Filters local-step test results to source locations to avoid including summary-only nodes.
rust/ql/test/library-tests/dataflow/local/DataFlowStep.expected	Updates expected local-step results after filtering.
rust/ql/test/library-tests/dataflow/global/viableCallable.ql	Tightens viable-callable test results to source/implicit-deref calls.
rust/ql/test/library-tests/dataflow/global/viableCallable.expected	Updates expected viable-callable results based on the refined query predicate.
rust/ql/test/library-tests/dataflow/global/main.rs	Makes source a const fn and adds a module testing const/static value flows (incl. static mut).
rust/ql/test/library-tests/dataflow/global/inline-flow.expected	Updates inline-flow expected edges/nodes/subpaths to reflect new const/static dataflow modeling.
rust/ql/test/library-tests/controlflow/Cfg.expected	Updates CFG expected output to reflect skipping const/static items in CFG construction.
rust/ql/test/library-tests/const_access/main.rs	Extends const-access tests to cover more contexts and const shadowing via inner items.
rust/ql/test/library-tests/const_access/const_access.ql	Enhances the const-access test harness to disambiguate shadowed consts using line comments.
rust/ql/test/library-tests/const_access/const_access.expected	Updates expected const-access results (including improved toString output and added cases).
rust/ql/test/extractor-tests/macro-expansion/test.expected	Updates extractor macro-expansion expectations to match new const string rendering.
rust/ql/test/extractor-tests/macro-expansion/PrintAst.expected	Updates AST print expectations to match new const string rendering.
rust/ql/test/extractor-tests/generated/Static/Static.expected	Updates generated extractor expectations to match new static string rendering.
rust/ql/test/extractor-tests/generated/ExternItemList/ExternItemList.expected	Updates generated extractor expectations to match new static string rendering.
rust/ql/test/extractor-tests/generated/Const/Const.expected	Updates generated extractor expectations to match new const string rendering.
rust/ql/lib/rust.qll	Exports the new StaticAccess element API from the top-level Rust library.
rust/ql/lib/codeql/rust/internal/PathResolution.qll	Adds static item nodes to path resolution with canonical-path handling.
rust/ql/lib/codeql/rust/elements/StaticAccess.qll	Introduces the public StaticAccess/read/write access classes.
rust/ql/lib/codeql/rust/elements/internal/StaticImpl.qll	Implements Static helpers (getAnAccess), StaticAccess, and improved toString for statics.
rust/ql/lib/codeql/rust/elements/internal/ConstImpl.qll	Adds getAnAccess and improved toString for const items.
rust/ql/lib/codeql/rust/elements/internal/AstNodeImpl.qll	Adjusts enclosing CFG-scope handling to treat const/static specially.
rust/ql/lib/codeql/rust/dataflow/internal/Node.qll	Adds a dedicated dataflow node kind for static items.
rust/ql/lib/codeql/rust/dataflow/internal/DataFlowImpl.qll	Adds jump-step modeling for flows between const/static bodies and their accesses.
rust/ql/lib/codeql/rust/controlflow/internal/Scope.qll	Introduces a special “source-file scope” for const/static initialization contexts (no CFG computed).
rust/ql/lib/codeql/rust/controlflow/internal/ControlFlowGraphImpl.qll	Excludes const/static items from CFG item trees.
rust/ql/.gitattributes	Marks StaticImpl.qll as no longer linguist-generated.
rust/ql/.generated.list	Removes StaticImpl.qll from the generated-file tracking list.

Copilot's findings

• Files reviewed: 31/35 changed files
• Comments generated: 1

[geoffw0]

Code changes LGTM. Impact on tests and DCA look really good as well. 👍

[geoffw0]

I can see here (and in one of the new tests) that we assume all writes to a static could (via the two dataflow steps) reach all reads. This seems like a reasonable approximation, and I think it's what we do in other languages that have similar features.

[hvitved]

Yes, it is similar to what we do in other languages.