blob: 5535868bd7eb81d4bf89db776779a09c8575f541 [file] [log] [blame]
"""Starlark helpers for Objective-C protos."""
# State constants for objc_proto_camel_case_name.
_last_was_other = 0
_last_was_lowercase = 1
_last_was_uppercase = 2
_last_was_number = 3
def objc_proto_camel_case_name(name):
"""A Starlark version of the ObjC generator's CamelCase name transform.
This needs to track
src/google/protobuf/compiler/objectivec/'s UnderscoresToCamelCase()
NOTE: This code is written to model the C++ in protoc's ObjC generator so it
is easier to confirm that the algorithms between the implementations match.
The customizations for starlark performance are:
- The cascade within the loop is reordered and special cases "_" to
optimize for google3 inputs.
- The "last was" state is handled via integers instead of three booleans.
The `first_capitalized` argument in the C++ code is left off this code and
it acts as if the value were `True`.
name: The proto file name to convert to camel case. The extension should
already be removed.
The converted proto name to camel case.
segments = []
current = ""
last_was = _last_was_other
for c in name.elems():
if c.islower():
# lowercase letter can follow a lowercase or uppercase letter.
if last_was != _last_was_lowercase and last_was != _last_was_uppercase:
current = c.upper()
current += c
last_was = _last_was_lowercase
elif c == "_": # more common than rest, special case it.
last_was = _last_was_other
elif c.isdigit():
if last_was != _last_was_number:
current = ""
current += c
last_was = _last_was_number
elif c.isupper():
if last_was != _last_was_uppercase:
current = c
current += c.lower()
last_was = _last_was_uppercase
last_was = _last_was_other
result = ""
for x in segments:
if x in ("Url", "Http", "Https"):
result += x.upper()
result += x
return result