Make Python rules in Bazel actually work.

In particular: add a BazelPythonSemantics implementation and the respective RuleConfiguredTarget factories, rule class definitions and hook them up with BazelRuleClassProvider. Add implicit dependencies (2to3 is just a stub script for now that always fails) and a tiny exampe.

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MOS_MIGRATED_REVID=89691827

3 files changed, 19 insertions, 0 deletions

diff --git a/examples/py_native/BUILD b/examples/py_native/BUILD
new file mode 100644
index 0000000000..3d8de94251
--- /dev/null
+++ b/examples/py_native/BUILD
@@ -0,0 +1,10 @@
+py_binary(
+    name = "bin",
+    srcs = ["bin.py"],
+    deps = [":lib"],
+)
+
+py_library(
+    name = "lib",
+    srcs = ["lib.py"],
+)
diff --git a/examples/py_native/bin.py b/examples/py_native/bin.py
new file mode 100644
index 0000000000..f79379a237
--- /dev/null
+++ b/examples/py_native/bin.py
@@ -0,0 +1,4 @@
+"""A tiny example binary for the native Python rules of Bazel."""
+from examples.py_native.lib import GetNumber
+
+print "The number is %d" % GetNumber()
diff --git a/examples/py_native/lib.py b/examples/py_native/lib.py
new file mode 100644
index 0000000000..44522e0fe9
--- /dev/null
+++ b/examples/py_native/lib.py
@@ -0,0 +1,5 @@
+"""A tiny example binary for the native Python rules of Bazel."""
+
+
+def GetNumber():
+  return 42