Use None as default arguments.

As per
https://docs.bazel.build/versions/main/skylark/macros.html#conventions

Default values for macros should be None.

Test: TH
Bug: 209506769

Change-Id: Ia8d8889cec8e7699b3177c3d479d145fc08c8a21

2 files changed, 21 insertions, 8 deletions

diff --git a/dist/dist.bzl b/dist/dist.bzl
index ea50148..46aa6e5 100644
--- a/dist/dist.bzl
+++ b/dist/dist.bzl
@@ -39,7 +39,6 @@ _generate_dist_manifest = rule(
     doc = """Generate a manifest of files to be dist to a directory.""",
     attrs = {
         "data": attr.label_list(
-            mandatory = True,
             allow_files = True,
             doc = """Files or targets to copy to the dist dir.
 
@@ -47,7 +46,6 @@ In the case of targets, the rule copies the list of `files` from the target's De
 """,
         ),
         "archives": attr.label_list(
-            mandatory = True,
             allow_files = [".tar.gz", ".tar"],
             doc = """Files or targets to be extracted to the dist dir.
 
@@ -57,7 +55,10 @@ In the case of targets, the rule copies the list of `files` from the target's De
     },
 )
 
-def copy_to_dist_dir(name, data = [], archives = []):
+def copy_to_dist_dir(
+        name,
+        data = None,
+        archives = None):
     """A dist rule to copy files out of Bazel's output directory into a custom location.
 
     Example:
diff --git a/docs/docs.bzl b/docs/docs.bzl
index 1fe02bc..e770fb6 100644
--- a/docs/docs.bzl
+++ b/docs/docs.bzl
@@ -21,10 +21,10 @@ def docs(
         name,
         srcs,
         default = None,
-        deps = [],
-        func_template = "//build/bazel_common_rules/docs:templates/func.vm",
-        provider_template = "//build/bazel_common_rules/docs:templates/provider.vm",
-        rule_template = "//build/bazel_common_rules/docs:templates/rule.vm"):
+        deps = None,
+        func_template = None,
+        provider_template = None,
+        rule_template = None):
     """Build docs.
 
     The following rules are also generated:
@@ -48,9 +48,21 @@ def docs(
         rule_template: Template for generating docs for rules.
     """
 
+    all_deps = []
+    all_deps += srcs
+    if deps != None:
+        all_deps += deps
+
+    if func_template == None:
+        func_template = "//build/bazel_common_rules/docs:templates/func.vm"
+    if provider_template == None:
+        provider_template = "//build/bazel_common_rules/docs:templates/provider.vm"
+    if rule_template == None:
+        rule_template = "//build/bazel_common_rules/docs:templates/rule.vm"
+
     bzl_library(
         name = name + "_deps",
-        srcs = srcs + deps,
+        srcs = all_deps,
     )
 
     all_markdown_files = []