Rename native.rule and native.rules to {existing_rule,existing_rules}

This is to avoid confusion between rule(), which declares a new build
rules, and native.rule(), which can only be used in macros to inspect
the BUILD file processed so far.

native.{rule,rules} is maintained and marked deprecated to smooth the
transition for early adopters.

--
MOS_MIGRATED_REVID=113250194

1 files changed, 7 insertions, 7 deletions

diff --git a/site/docs/skylark/cookbook.md b/site/docs/skylark/cookbook.md
index 60f441fc71..bf96adc55f 100644
--- a/site/docs/skylark/cookbook.md
+++ b/site/docs/skylark/cookbook.md
@@ -66,11 +66,11 @@ macro(name = "myrule")
 ## <a name="conditional-instantiation"></a>Conditional instantiation.
 
 Macros can look at previously instantiated rules. This is done with
-`native.rule`, which returns information on a single rule defined in the same
+`native.existing_rule`, which returns information on a single rule defined in the same
 `BUILD` file, eg.,
 
 ```python
-native.rule("descriptor_proto")
+native.existing_rule("descriptor_proto")
 ```
 
 This is useful to avoid instantiating the same rule twice, which is an
@@ -82,7 +82,7 @@ tests for diverse flavors of the same test.
 ```python
 def system_test(test_file, flavor):
   n = "system_test_%s_%s_test" % (test_file, flavor)
-  if native.rule(n) == None:
+  if native.existing_rule(n) == None:
     native.py_test(
       name = n,
       srcs = [ "test_driver.py", test_file ],
@@ -115,22 +115,22 @@ system_test_suite("thorough", flavors=["fast", "debug", "opt"], ["basic_test.py"
 
 Macros can collect information from the BUILD file as processed so far.  We call
 this aggregation. The typical example is collecting data from all rules of a
-certain kind.  This is done by calling `native.rules`, which returns a
+certain kind.  This is done by calling `native.existing_rules`, which returns a
 dictionary representing all rules defined so far in the current BUILD file. The
 dictionary has entries of the form `name` => `rule`, with the values using the
-same format as `native.rule`.
+same format as `native.existing_rule`.
 
 ```python
 def archive_cc_src_files(tag):
   """Create an archive of all C++ sources that have the given tag."""
   all_src = []
-  for r in native.rules().values():
+  for r in native.existing_rules().values():
     if tag in r["tags"] and r["kind"] == "cc_library":
       all_src.append(r["srcs"])
   native.genrule(cmd = "zip $@ $^", srcs = all_src, outs = ["out.zip"])
 ```
 
-Since `native.rules` constructs a potentially large dictionary, you should avoid
+Since `native.existing_rules` constructs a potentially large dictionary, you should avoid
 calling it repeatedly within BUILD file.
 
 ## <a name="empty"></a>Empty rule