//mojo:mojo.bzl

Build files should import these rules from @rules_mojo//mojo:defs.bzl.

mojo_binary

mojo_binary(name, deps, srcs, compile_flags, compile_string_flags, defines, includes, runtime_data)

Creates an executable.

Example:

mojo_binary(
    name = "hello",
    srcs = ["hello.mojo"],
)

Attributes

Name	Description
name	Name, required. A unique name for this target.
deps	List of labels, optional, defaults to []. The dependencies for this target. Use ll_library targets here. Other targets won’t work.
srcs	List of labels, optional, defaults to []. Compilable source files for this target. Allowed file extensions: [".mojo", ".🔥"]. Place headers in the hdrs attribute.
compile_flags	List of strings, optional, defaults to []. Flags for the compiler. Pass a list of strings here. For instance ["-O3", "-std=c++20"]. Split flag pairs -Xclang -somearg into separate flags ["-Xclang", "-somearg"]. Unavailable to downstream targets.
compile_string_flags	List of labels, optional, defaults to []. Flags for the compiler in the form of string_flags. Splits the values of each string_flag along colons like so: load(“@bazel_skylib//rules:common_settings .bzl”, “string_flag”) string_flag( name = “myflags”, build_setting_default = “a:b:c ”, ) mojo_library( # … # Equivalent to compile_flags = ["a", "b", "c"] compile_string_flags = [":myflags "], ) Useful for externally configurable build attributes, such as generated flags from Nix environments.
defines	List of strings, optional, defaults to []. Defines for this target. Pass a list of strings here. For instance ["MYDEFINE_1", "MYDEFINE_2"]. Unavailable to downstream targets.
includes	List of strings, optional, defaults to []. Include paths, relative to the target workspace. Uses -iquote. Useful if you need custom include prefix stripping for dynamic paths, for instance the ones generated by bzlmod. Instead of compile_flags = ["-iquoteexternal/mydep.someversion/include"], use includes = ["include"] to add the path to the workspace automatically. Expands paths starting with $(GENERATED) to the workspace location in the GENDIR path. Unavailable to downstream targets.
runtime_data	List of labels, optional, defaults to []. Extra files made available during test time.

mojo_library

mojo_library(name, deps, srcs, compile_flags, compile_string_flags, defines, includes)

Creates a Mojo package.

Example:

mojo_library(
    name = "mypackage",
    srcs = [
        "__init__.mojo",
        "my_package.mojo",
    ],
)

Attributes

Name	Description
name	Name, required. A unique name for this target.
deps	List of labels, optional, defaults to []. The dependencies for this target. Use ll_library targets here. Other targets won’t work.
srcs	List of labels, optional, defaults to []. Compilable source files for this target. Allowed file extensions: [".mojo", ".🔥"]. Place headers in the hdrs attribute.
compile_flags	List of strings, optional, defaults to []. Flags for the compiler. Pass a list of strings here. For instance ["-O3", "-std=c++20"]. Split flag pairs -Xclang -somearg into separate flags ["-Xclang", "-somearg"]. Unavailable to downstream targets.
compile_string_flags	List of labels, optional, defaults to []. Flags for the compiler in the form of string_flags. Splits the values of each string_flag along colons like so: load(“@bazel_skylib//rules:common_settings .bzl”, “string_flag”) string_flag( name = “myflags”, build_setting_default = “a:b:c ”, ) mojo_library( # … # Equivalent to compile_flags = ["a", "b", "c"] compile_string_flags = [":myflags "], ) Useful for externally configurable build attributes, such as generated flags from Nix environments.
defines	List of strings, optional, defaults to []. Defines for this target. Pass a list of strings here. For instance ["MYDEFINE_1", "MYDEFINE_2"]. Unavailable to downstream targets.
includes	List of strings, optional, defaults to []. Include paths, relative to the target workspace. Uses -iquote. Useful if you need custom include prefix stripping for dynamic paths, for instance the ones generated by bzlmod. Instead of compile_flags = ["-iquoteexternal/mydep.someversion/include"], use includes = ["include"] to add the path to the workspace automatically. Expands paths starting with $(GENERATED) to the workspace location in the GENDIR path. Unavailable to downstream targets.

mojo_test

mojo_test(name, deps, srcs, compile_flags, compile_string_flags, defines, includes, runtime_data)

Testable wrapper around mojo_binary.

Consider using this rule over Skylib’s native_test targets to propagate shared libraries to the test invocations.

Example:

mojo_test(
    name = "hello_test",
    srcs = ["my_test.mojo"],
)

Attributes

Name	Description
name	Name, required. A unique name for this target.
deps	List of labels, optional, defaults to []. The dependencies for this target. Use ll_library targets here. Other targets won’t work.
srcs	List of labels, optional, defaults to []. Compilable source files for this target. Allowed file extensions: [".mojo", ".🔥"]. Place headers in the hdrs attribute.
compile_flags	List of strings, optional, defaults to []. Flags for the compiler. Pass a list of strings here. For instance ["-O3", "-std=c++20"]. Split flag pairs -Xclang -somearg into separate flags ["-Xclang", "-somearg"]. Unavailable to downstream targets.
compile_string_flags	List of labels, optional, defaults to []. Flags for the compiler in the form of string_flags. Splits the values of each string_flag along colons like so: load(“@bazel_skylib//rules:common_settings .bzl”, “string_flag”) string_flag( name = “myflags”, build_setting_default = “a:b:c ”, ) mojo_library( # … # Equivalent to compile_flags = ["a", "b", "c"] compile_string_flags = [":myflags "], ) Useful for externally configurable build attributes, such as generated flags from Nix environments.
defines	List of strings, optional, defaults to []. Defines for this target. Pass a list of strings here. For instance ["MYDEFINE_1", "MYDEFINE_2"]. Unavailable to downstream targets.
includes	List of strings, optional, defaults to []. Include paths, relative to the target workspace. Uses -iquote. Useful if you need custom include prefix stripping for dynamic paths, for instance the ones generated by bzlmod. Instead of compile_flags = ["-iquoteexternal/mydep.someversion/include"], use includes = ["include"] to add the path to the workspace automatically. Expands paths starting with $(GENERATED) to the workspace location in the GENDIR path. Unavailable to downstream targets.
runtime_data	List of labels, optional, defaults to []. Extra files made available during test time.

expand_includes

expand_includes(ctx, include_string)

Prefix include_string with the path to the workspace root.

If include_string starts with $(GENERATED), prefixes with theGENDIR path as well.

Args:

Name	Description
ctx
include_string

find_package_dir

find_package_dir(ctx)

Find the directory to turn into a package.

Each directory with an __init__.mojo file corresponds to a package.

This function constructs a package from the first __init__.mojo file it finds, starting from the top level directory. If you have files like this:

mypackage/
    __init__.mojo
    subpackage/
        __init__.mojo

you’ll get an output package mypackage.mojopkg.

Args:

Name	Description
ctx	The rule context.

Returns:

The package directory.

mojo_artifact

mojo_artifact(ctx, filename)

Return a string of the form "{ctx.label.name}/filename".

Encapsulate intermediary build artifacts to avoid name clashes for files of the same name built by targets in the same build invocation.

Args:

Name	Description
ctx	The build context.
filename	defaults to None. An optional string representing a filename. If omitted, creates a path of the form "{ctx.label.name}".

resolve_rule_inputs

resolve_rule_inputs(ctx)

Gather the inputs for downstream actions.

Args:

Name	Description
ctx	The rule context.

Returns:

A tuple (defines, includes). See //mojo:actions .bzl for usage.