Query - Aspect Build

function Query.eval

def Query.eval(
*,
flags: list[str | (str, str)] = [],
announce_version: bool = False,
announce_command: bool = False
) -> typing.Iterable[generated_file | package_group | rule | source_file]

The query system provides a programmatic interface for analyzing build dependencies and target relationships. Queries are constructed using a chain API and are lazily evaluated only when .eval() is explicitly called. The entry point is ctx.bazel.query(), which returns a query for creating initial query expressions. Most operations operate on query objects, which represent sets of targets that can be filtered, transformed, and combined. Example

**Query** dependencies of a target
deps = ctx.bazel.query().targets("//myapp:main").deps()
all_deps: target_set = deps.eval()

**Chain** multiple operations
sources = ctx.bazel.query().targets("//myapp:main")
    .deps()
    .kind("source file")
    .eval()

Fails with Bazel’s own stderr if the query exits non-zero (bad expression, BUILD evaluation error, …), rather than returning an empty target set — a failed query is not the same as one that matched nothing. Parameters

flags: - Command flags to pass to bazel query (between the expression and --output). Callers that run query alongside build / test under --ignore_all_rc_files MUST forward the rc-expanded command flags here, so the query resolves external repositories the same way the build does (e.g. an rc-set --noenable_bzlmod / --enable_workspace). Omitting them lets the query diverge from the build and fail on repos the build can see. Accepts the same str | (str, version-constraint) shape as ctx.bazel.build / .test; version-gated flags are filtered against the running Bazel version identically.
announce_version: - Print an INFO: Bazel <version> line before spawning. Resolved from the --announce-bazel-version task flag.
announce_command: - Print an INFO: Spawning: <command> line before spawning. Resolved from the --announce-bazel-command task flag. Both mirror the ctx.bazel.build / .test disclosure.

function Query.raw

def Query.raw(
expr: str,
/
) -> bazel.query.Query

Replaces the query expression with a raw query expression string. This escape hatch allows direct use of the underlying query language for complex cases, while still supporting further chaining.

**Complex** intersection query
complex = ctx.bazel.query().raw("deps(//foo) intersect kind('test', //bar:*)")

**Path**-based query
path_query = ctx.bazel.query().raw("somepath(//start, //end)")

**Chaining** after raw
filtered = complex.kind("source file")