A rule that copies source files to the output tree.
This rule uses a Bash command (diff) on Linux/macOS/non-Windows, and a cmd.exe
command (fc.exe) on Windows (no Bash is required).
Originally authored in rules_nodejs
https://github.com/bazelbuild/rules_nodejs/blob/8b5d27400db51e7027fe95ae413eeabea4856f8e/internal/common/copy_to_bin.bzl
## copy_file_to_bin_action
copy_file_to_bin_action(ctx, file)
Factory function that creates an action to copy a file to the output tree.
File are copied to the same workspace-relative path. The resulting files is
returned.
If the file passed in is already in the output tree is then it is returned
without a copy action.
To use `copy_file_to_bin_action` in your own rules, you need to include the toolchains it uses
in your rule definition. For example:
```starlark
load("@aspect_bazel_lib//lib:copy_to_bin.bzl", "COPY_FILE_TO_BIN_TOOLCHAINS")
my_rule = rule(
...,
toolchains = COPY_FILE_TO_BIN_TOOLCHAINS,
)
```
Additionally, you must ensure that the coreutils toolchain is has been registered in your
WORKSPACE if you are not using bzlmod:
```starlark
load("@aspect_bazel_lib//lib:repositories.bzl", "register_coreutils_toolchains")
register_coreutils_toolchains()
```
**PARAMETERS**
| Name | Description | Default Value |
| :------------- | :------------- | :------------- |
| ctx | The rule context. | none |
| file | The file to copy. | none |
**RETURNS**
A File in the output tree.
## copy_files_to_bin_actions
copy_files_to_bin_actions(ctx, files)
Factory function that creates actions to copy files to the output tree.
Files are copied to the same workspace-relative path. The resulting list of
files is returned.
If a file passed in is already in the output tree is then it is added
directly to the result without a copy action.
**PARAMETERS**
| Name | Description | Default Value |
| :------------- | :------------- | :------------- |
| ctx | The rule context. | none |
| files | List of File objects. | none |
**RETURNS**
List of File objects in the output tree.
## copy_to_bin
copy_to_bin(name, srcs, kwargs)
Copies a source file to output tree at the same workspace-relative path.
e.g. `<execroot>/path/to/file -> <execroot>/bazel-out/<platform>/bin/path/to/file`
If a file passed in is already in the output tree is then it is added directly to the
DefaultInfo provided by the rule without a copy.
This is useful to populate the output folder with all files needed at runtime, even
those which aren't outputs of a Bazel rule.
This way you can run a binary in the output folder (execroot or runfiles_root)
without that program needing to rely on a runfiles helper library or be aware that
files are divided between the source tree and the output tree.
**PARAMETERS**
| Name | Description | Default Value |
| :------------- | :------------- | :------------- |
| name | Name of the rule. | none |
| srcs | A list of labels. File(s) to copy. | none |
| kwargs | further keyword arguments, e.g. visibility | none |