Add docstring to providers to make buildifier happy.

RELNOTES: None.
PiperOrigin-RevId: 334807705
Change-Id: If0c97e6a464126367005143313dc4ddc5b47bdea

cc/cc_toolchain_config_lib.bzl

@@ -35,7 +35,10 @@ def _check_is_nonempty_list(obj, parameter_name, method_name):
         fail("{} parameter of {} must be a nonempty list."
             .format(parameter_name, method_name))
 
-EnvEntryInfo = provider(fields = ["key", "value", "type_name"])
+EnvEntryInfo = provider(
+    "A key/value pair to be added as an environment variable.",
+    fields = ["key", "value", "type_name"],
+)
 
 def env_entry(key, value):
     """ A key/value pair to be added as an environment variable.
@@ -57,7 +60,10 @@ def env_entry(key, value):
     _check_is_nonempty_string(value, "value", "env_entry")
     return EnvEntryInfo(key = key, value = value, type_name = "env_entry")
 
-VariableWithValueInfo = provider(fields = ["name", "value", "type_name"])
+VariableWithValueInfo = provider(
+    "Represents equality check between a variable and a certain value.",
+    fields = ["name", "value", "type_name"],
+)
 
 def variable_with_value(name, value):
     """ Represents equality check between a variable and a certain value.
@@ -81,7 +87,10 @@ def variable_with_value(name, value):
         type_name = "variable_with_value",
     )
 
-MakeVariableInfo = provider(fields = ["name", "value", "type_name"])
+MakeVariableInfo = provider(
+    "A make variable that is made accessible to rules.",
+    fields = ["name", "value", "type_name"],
+)
 
 def make_variable(name, value):
     """ A make variable that is made accessible to rules."""
@@ -93,7 +102,10 @@ def make_variable(name, value):
         type_name = "make_variable",
     )
 
-FeatureSetInfo = provider(fields = ["features", "type_name"])
+FeatureSetInfo = provider(
+    "A set of features.",
+    fields = ["features", "type_name"],
+)
 
 def feature_set(features = []):
     """ A set of features.
@@ -110,7 +122,10 @@ def feature_set(features = []):
     _check_right_type(features, [], "features", "feature_set")
     return FeatureSetInfo(features = features, type_name = "feature_set")
 
-WithFeatureSetInfo = provider(fields = ["features", "not_features", "type_name"])
+WithFeatureSetInfo = provider(
+    "A set of positive and negative features.",
+    fields = ["features", "not_features", "type_name"],
+)
 
 def with_feature_set(features = [], not_features = []):
     """ A set of positive and negative features.
@@ -133,7 +148,10 @@ def with_feature_set(features = [], not_features = []):
         type_name = "with_feature_set",
     )
 
-EnvSetInfo = provider(fields = ["actions", "env_entries", "with_features", "type_name"])
+EnvSetInfo = provider(
+    "Groups a set of environment variables to apply for certain actions.",
+    fields = ["actions", "env_entries", "with_features", "type_name"],
+)
 
 def env_set(actions, env_entries = [], with_features = []):
     """ Groups a set of environment variables to apply for certain actions.
@@ -166,7 +184,9 @@ def env_set(actions, env_entries = [], with_features = []):
         type_name = "env_set",
     )
 
-FlagGroupInfo = provider(fields = [
+FlagGroupInfo = provider(
+    "A group of flags. Supports parametrization via variable expansion.",
+    fields = [
         "flags",
         "flag_groups",
         "iterate_over",
@@ -176,7 +196,8 @@ FlagGroupInfo = provider(fields = [
         "expand_if_false",
         "expand_if_equal",
         "type_name",
-])
+    ],
+)
 
 def flag_group(
         flags = [],
@@ -285,12 +306,15 @@ def flag_group(
         type_name = "flag_group",
     )
 
-FlagSetInfo = provider(fields = [
+FlagSetInfo = provider(
+    "A set of flags to be expanded in the command line for specific actions.",
+    fields = [
         "actions",
         "with_features",
         "flag_groups",
         "type_name",
-])
+    ],
+)
 
 def flag_set(
         actions = [],
@@ -322,7 +346,9 @@ def flag_set(
         type_name = "flag_set",
     )
 
-FeatureInfo = provider(fields = [
+FeatureInfo = provider(
+    "Contains all flag specifications for one feature.",
+    fields = [
         "name",
         "enabled",
         "flag_sets",
@@ -331,7 +357,8 @@ FeatureInfo = provider(fields = [
         "implies",
         "provides",
         "type_name",
-])
+    ],
+)
 
 def feature(
         name,
@@ -395,7 +422,10 @@ def feature(
         type_name = "feature",
     )
 
-ToolPathInfo = provider(fields = ["name", "path", "type_name"])
+ToolPathInfo = provider(
+    "Tool locations.",
+    fields = ["name", "path", "type_name"],
+)
 
 def tool_path(name, path):
     """ Tool locations.
@@ -416,7 +446,10 @@ def tool_path(name, path):
     _check_is_nonempty_string(path, "path", "tool_path")
     return ToolPathInfo(name = name, path = path, type_name = "tool_path")
 
-ToolInfo = provider(fields = ["path", "with_features", "execution_requirements", "type_name"])
+ToolInfo = provider(
+    "Describes a tool associated with a crosstool action config.",
+    fields = ["path", "with_features", "execution_requirements", "type_name"],
+)
 
 def tool(path, with_features = [], execution_requirements = []):
     """ Describes a tool associated with a crosstool action config.
@@ -448,7 +481,9 @@ def tool(path, with_features = [], execution_requirements = []):
         type_name = "tool",
     )
 
-ActionConfigInfo = provider(fields = [
+ActionConfigInfo = provider(
+    "Configuration of a Bazel action.",
+    fields = [
         "config_name",
         "action_name",
         "enabled",
@@ -456,7 +491,8 @@ ActionConfigInfo = provider(fields = [
         "flag_sets",
         "implies",
         "type_name",
-])
+    ],
+)
 
 def action_config(
         action_name,
@@ -506,12 +542,15 @@ def action_config(
         type_name = "action_config",
     )
 
-ArtifactNamePatternInfo = provider(fields = [
+ArtifactNamePatternInfo = provider(
+    "The name for an artifact of a given category of input or output artifacts to an action.",
+    fields = [
         "category_name",
         "prefix",
         "extension",
         "type_name",
-])
+    ],
+)
 
 def artifact_name_pattern(category_name, prefix, extension):
     """ The name for an artifact of a given category of input or output artifacts to an action.

examples/experimental_cc_shared_library.bzl

@@ -17,11 +17,13 @@ load("//cc:find_cc_toolchain.bzl", "find_cc_toolchain")
 LINKABLE_MORE_THAN_ONCE = "LINKABLE_MORE_THAN_ONCE"
 
 CcSharedLibraryPermissionsInfo = provider(
+    "Permissions for a cc shared library.",
     fields = {
         "targets": "Matches targets that can be exported.",
     },
 )
 GraphNodeInfo = provider(
+    "Nodes in the graph of shared libraries.",
     fields = {
         "children": "Other GraphNodeInfo from dependencies of this target",
         "label": "Label of the target visited",
@@ -29,6 +31,7 @@ GraphNodeInfo = provider(
     },
 )
 CcSharedLibraryInfo = provider(
+    "Information about a cc shared library.",
     fields = {
         "dynamic_deps": "All shared libraries depended on transitively",
         "exports": "cc_libraries that are linked statically and exported",