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ngiloq6laurentlb
ngiloq6
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laurentlb
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copy_file: add rule and tests (#123)
This PR adds two new rules: copy_file and copy_xfile. Both rules solve a common problem: to copy one file to another location. The problem is routinely solved using a genrule. That however requires Bash, since genrules execute Bash commands. Requiring Bash is a problem on Windows. The new rules do not require Bash on Windows (only on other platforms). The only difference between the rules is that copy_xfile creates an executable file while copy_file doesn't. See bazelbuild/bazel#4319
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‎docs/BUILD

+7
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@@ -92,6 +92,13 @@ stardoc(
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deps = ["//lib:versions"],
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)
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stardoc(
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name = "copy_file_docs",
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out = "copy_file_doc_gen.md",
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input = "//rules:copy_file.bzl",
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deps = ["//rules:copy_file"],
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)
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stardoc(
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name = "maprule_docs",
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out = "maprule_doc_gen.md",

‎rules/BUILD

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Original file line numberDiff line numberDiff line change
@@ -10,6 +10,18 @@ bzl_library(
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deps = ["//lib:new_sets"],
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)
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bzl_library(
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name = "copy_file",
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srcs = ["copy_file.bzl"],
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deps = [":copy_file_private"],
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)
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bzl_library(
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name = "copy_file_private",
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srcs = ["copy_file_private.bzl"],
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visibility = ["//visibility:private"],
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)
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bzl_library(
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name = "maprule",
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srcs = ["maprule.bzl"],

‎rules/copy_file.bzl

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# Copyright 2019 The Bazel Authors. All rights reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""A rule that copies a file to another place.
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native.genrule() is sometimes used to copy files (often wishing to rename them).
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The 'copy_file' rule does this with a simpler interface than genrule.
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The rule uses a Bash command on Linux/macOS/non-Windows, and a cmd.exe command
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on Windows (no Bash is required).
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"""
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load(
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":copy_file_private.bzl",
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_copy_file = "copy_file",
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)
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copy_file = _copy_file

‎rules/copy_file_private.bzl

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# Copyright 2019 The Bazel Authors. All rights reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""Implementation of copy_file macro and underlying rules.
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These rules copy a file to another location using Bash (on Linux/macOS) or
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cmd.exe (on Windows). '_copy_xfile' marks the resulting file executable,
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'_copy_file' does not.
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"""
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def _common_impl(ctx, is_executable):
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if ctx.attr.is_windows:
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# Most Windows binaries built with MSVC use a certain argument quoting
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# scheme. Bazel uses that scheme too to quote arguments. However,
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# cmd.exe uses different semantics, so Bazel's quoting is wrong here.
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# To fix that we write the command to a .bat file so no command line
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# quoting or escaping is required.
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bat = ctx.actions.declare_file(ctx.label.name + "-cmd.bat")
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ctx.actions.write(
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output = bat,
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# Do not use lib/shell.bzl's shell.quote() method, because that uses
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# Bash quoting syntax, which is different from cmd.exe's syntax.
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content = "@copy /Y \"%s\" \"%s\" >NUL" % (
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ctx.file.src.path.replace("/", "\\"),
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ctx.outputs.out.path.replace("/", "\\"),
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),
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is_executable = True,
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)
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ctx.actions.run(
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inputs = [ctx.file.src, bat],
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outputs = [ctx.outputs.out],
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executable = "cmd.exe",
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arguments = ["/C", bat.path.replace("/", "\\")],
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mnemonic = "CopyFile",
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progress_message = "Copying files",
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use_default_shell_env = True,
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)
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else:
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ctx.actions.run_shell(
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inputs = [ctx.file.src],
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outputs = [ctx.outputs.out],
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command = "cp -f \"$1\" \"$2\"",
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arguments = [ctx.file.src.path, ctx.outputs.out.path],
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mnemonic = "CopyFile",
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progress_message = "Copying files",
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use_default_shell_env = True,
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)
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files = depset(direct = [ctx.outputs.out])
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runfiles = ctx.runfiles(files = [ctx.outputs.out])
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if is_executable:
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return [DefaultInfo(files = files, runfiles = runfiles, executable = ctx.outputs.out)]
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else:
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return [DefaultInfo(files = files, runfiles = runfiles)]
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def _impl(ctx):
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return _common_impl(ctx, False)
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def _ximpl(ctx):
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return _common_impl(ctx, True)
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_ATTRS = {
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"src": attr.label(mandatory = True, allow_single_file = True),
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"out": attr.output(mandatory = True),
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"is_windows": attr.bool(mandatory = True),
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}
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_copy_file = rule(
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implementation = _impl,
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provides = [DefaultInfo],
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attrs = _ATTRS,
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)
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_copy_xfile = rule(
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implementation = _ximpl,
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executable = True,
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provides = [DefaultInfo],
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attrs = _ATTRS,
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)
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def copy_file(name, src, out, is_executable = False, **kwargs):
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"""Copies a file to another location.
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`native.genrule()` is sometimes used to copy files (often wishing to rename them). The 'copy_file' rule does this with a simpler interface than genrule.
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This rule uses a Bash command on Linux/macOS/non-Windows, and a cmd.exe command on Windows (no Bash is required).
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Args:
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name: Name of the rule.
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src: A Label. The file to make a copy of. (Can also be the label of a rule
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that generates a file.)
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out: Path of the output file, relative to this package.
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is_executable: A boolean. Whether to make the output file executable. When
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True, the rule's output can be executed using `bazel run` and can be
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in the srcs of binary and test rules that require executable sources.
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**kwargs: further keyword arguments, e.g. `visibility`
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"""
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if is_executable:
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_copy_xfile(
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name = name,
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src = src,
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out = out,
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is_windows = select({
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"@bazel_tools//src/conditions:host_windows": True,
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"//conditions:default": False,
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}),
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**kwargs
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)
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else:
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_copy_file(
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name = name,
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src = src,
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out = out,
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is_windows = select({
126+
"@bazel_tools//src/conditions:host_windows": True,
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"//conditions:default": False,
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}),
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**kwargs
130+
)

‎tests/BUILD

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@@ -16,6 +16,11 @@ load(":versions_tests.bzl", "versions_test_suite")
1616

1717
licenses(["notice"])
1818

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exports_files(
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["unittest.bash"],
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visibility = ["//tests:__subpackages__"],
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)
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1924
build_test_test_suite()
2025

2126
collections_test_suite()

‎tests/copy_file/BUILD

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# This package aids testing the 'copy_file' rule.
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#
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# The package contains 4 copy_file rules:
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# - 'copy_src' and 'copy_gen' copy a source file and a generated file
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# respectively
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# - 'copy_xsrc' and 'copy_xgen' copy a source file and a generated file
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# respectively (both are shell scripts), and mark their output as executable
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#
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# The generated file is the output of the 'gen' genrule.
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#
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# The 'bin_src' and 'bin_gen' rules are sh_binary rules. They use the
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# 'copy_xsrc' and 'copy_xgen' rules respectively. The sh_binary rule requires
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# its source to be executable, so building these two rules successfully means
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# that 'copy_file' managed to make its output executable.
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#
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# The 'run_executables' genrule runs the 'bin_src' and 'bin_gen' binaries,
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# partly to ensure they can be run, and partly so we can observe their output
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# and assert the contents in the 'copy_file_tests' test.
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#
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# The 'file_deps' filegroup depends on 'copy_src'. The filegroup rule uses the
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# DefaultInfo.files field from its dependencies. When we data-depend on the
22+
# filegroup from 'copy_file_tests', we transitively data-depend on the
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# DefaultInfo.files of the 'copy_src' rule.
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#
25+
# The 'copy_file_tests' test is the actual integration test. It data-depends
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# on:
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# - the 'run_executables' rule, to get the outputs of 'bin_src' and 'bin_gen'
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# - the 'file_deps' rule, and by nature of using a filegroup, we get the files
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# from the DefaultInfo.files of the 'copy_file' rule, and thereby assert that
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# that field contains the output file of the rule
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# - the 'copy_nonempty_text' rule, and thereby on the DefaultInfo.runfiles field
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# of it, so we assert that that field contains the output file of the rule
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load("//rules:copy_file.bzl", "copy_file")
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package(default_testonly = 1)
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sh_test(
39+
name = "copy_file_tests",
40+
srcs = ["copy_file_tests.sh"],
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data = [
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":run_executables",
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# Use DefaultInfo.files from 'copy_src' (via 'file_deps').
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":file_deps",
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# Use DefaultInfo.runfiles from 'copy_gen'.
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":copy_gen",
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"//tests:unittest.bash",
48+
],
49+
deps = ["@bazel_tools//tools/bash/runfiles"],
50+
)
51+
52+
filegroup(
53+
name = "file_deps",
54+
# Use DefaultInfo.files from 'copy_src'.
55+
srcs = [
56+
":copy_src",
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],
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)
59+
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# If 'run_executables' is built, then 'bin_gen' and 'bin_src' are
61+
# executable, asserting that copy_file makes the output executable.
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genrule(
63+
name = "run_executables",
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outs = [
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"xsrc-out.txt",
66+
"xgen-out.txt",
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],
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cmd = ("$(location :bin_src) > $(location xsrc-out.txt) && " +
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"$(location :bin_gen) > $(location xgen-out.txt)"),
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output_to_bindir = 1,
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tools = [
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":bin_gen",
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":bin_src",
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],
75+
)
76+
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# If 'bin_src' is built, then 'copy_xsrc' made its output executable.
78+
sh_binary(
79+
name = "bin_src",
80+
srcs = [":copy_xsrc"],
81+
)
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# If 'bin_gen' is built, then 'copy_xgen' made its output executable.
84+
sh_binary(
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name = "bin_gen",
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srcs = [":copy_xgen"],
87+
)
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copy_file(
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name = "copy_src",
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src = "a.txt",
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out = "out/a-out.txt",
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)
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copy_file(
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name = "copy_gen",
97+
src = ":gen",
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out = "out/gen-out.txt",
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)
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copy_file(
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name = "copy_xsrc",
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src = "a.txt",
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out = "xout/a-out.sh",
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is_executable = True,
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)
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copy_file(
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name = "copy_xgen",
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src = ":gen",
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out = "xout/gen-out.sh",
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is_executable = True,
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)
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genrule(
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name = "gen",
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outs = ["b.txt"],
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cmd = "echo -e '#!/bin/bash\necho potato' > $@",
119+
)

‎tests/copy_file/a.txt

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#!/bin/bash
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echo aaa

‎tests/copy_file/copy_file_tests.sh

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# Copyright 2019 The Bazel Authors. All rights reserved.
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#
3+
# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
7+
# http://www.apache.org/licenses/LICENSE-2.0
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#
9+
# Unless required by applicable law or agreed to in writing, software
10+
# distributed under the License is distributed on an "AS IS" BASIS,
11+
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12+
# See the License for the specific language governing permissions and
13+
# limitations under the License.
14+
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# --- begin runfiles.bash initialization ---
16+
# Copy-pasted from Bazel's Bash runfiles library (tools/bash/runfiles/runfiles.bash).
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set -euo pipefail
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if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
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if [[ -f "$0.runfiles_manifest" ]]; then
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export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
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elif [[ -f "$0.runfiles/MANIFEST" ]]; then
22+
export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
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elif [[ -f "$0.runfiles/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
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export RUNFILES_DIR="$0.runfiles"
25+
fi
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fi
27+
if [[ -f "${RUNFILES_DIR:-/dev/null}/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
28+
source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
29+
elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
30+
source "$(grep -m1 "^bazel_tools/tools/bash/runfiles/runfiles.bash " \
31+
"$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-)"
32+
else
33+
echo >&2 "ERROR: cannot find @bazel_tools//tools/bash/runfiles:runfiles.bash"
34+
exit 1
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fi
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# --- end runfiles.bash initialization ---
37+
38+
source "$(rlocation bazel_skylib/tests/unittest.bash)" \
39+
|| { echo "Could not source bazel_skylib/tests/unittest.bash" >&2; exit 1; }
40+
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function test_copy_src() {
42+
cat "$(rlocation bazel_skylib/tests/copy_file/out/a-out.txt)" >"$TEST_log"
43+
expect_log '^#!/bin/bash$'
44+
expect_log '^echo aaa$'
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}
46+
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function test_copy_gen() {
48+
cat "$(rlocation bazel_skylib/tests/copy_file/out/gen-out.txt)" >"$TEST_log"
49+
expect_log '^#!/bin/bash$'
50+
expect_log '^echo potato$'
51+
}
52+
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function test_copy_xsrc() {
54+
cat "$(rlocation bazel_skylib/tests/copy_file/xsrc-out.txt)" >"$TEST_log"
55+
expect_log '^aaa$'
56+
}
57+
58+
function test_copy_xgen() {
59+
cat "$(rlocation bazel_skylib/tests/copy_file/xgen-out.txt)" >"$TEST_log"
60+
expect_log '^potato$'
61+
}
62+
63+
run_suite "copy_file_tests test suite"

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