[infra] Add a check for incompatible changes to ir.proto
This check is not designed to be all encompassing of any possible
incompatible change, just catching enumerated values changing in the
proto, and existing types being removed.
The parsing in the change is simple, not importing and using the proto
library, so there is lots of corner cases that will probably cause it to
bail, but it works for the existing ir.proto file and should work
reasonably for future versions that are well formed and have a readable
style. It not handling tricky 'technically' valid syntax is considered a
feature not a bug.
This check also hardcodes the location of the ir.proto file. This path
isn't expected to change, and the check can be updated if it does need
to move.
Fixes: 422414025
Change-Id: Ib4f51b21f90913429fe7af58d62389cc6e3e4768
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/247174
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Auto-Submit: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dan sinclair <dsinclair@chromium.org>
diff --git a/PRESUBMIT.py b/PRESUBMIT.py
index 6f4eb51..5ce900c 100644
--- a/PRESUBMIT.py
+++ b/PRESUBMIT.py
@@ -138,6 +138,93 @@
return []
+def _CalculateEnumeratedEntriesAndTypes(lines):
+ """Returns a dictionary of enumerated entries, and a list of all the 'types' encountered.
+
+ The implemented parsing is unsophisticated, and assumes a readable/well-formed .proto file.
+ Things like unmatched '{}'s will cause a crash. Missing ';'s or writing something like `} message Foo {` will also
+ cause misbehaviour.
+ Constructs like this are normally bad style, so if really needed, adding support for them is left as an exercise for
+ the reader.
+ """
+ push_re = re.compile(r'(\w+) {(.*)')
+ value_re = re.compile(r'(\w+) = (\d+);(.*)')
+ pop_re = re.compile(r'}(.*)')
+
+ prefix_stack = []
+ prefix_str = ""
+ enumerated_entries = {}
+ types = []
+ for l in lines:
+ l = l.strip().rstrip()
+ l = l.split("//", 1)[0]
+ while l:
+ if match := re.search(push_re, l):
+ prefix_stack.append(match.group(1))
+ prefix_str = '.'.join(prefix_stack)
+ types.append(prefix_str)
+ l = match.group(2)
+ continue
+ if match := re.search(value_re, l):
+ enumerated_entries[
+ f"{prefix_str}.{match.group(1)}"] = match.group(2)
+ l = match.group(2)
+ continue
+ if match := re.search(pop_re, l):
+ prefix_stack.pop()
+ prefix_str = '_'.join(prefix_stack)
+ l = match.group(1)
+ continue
+ l = ""
+
+ return enumerated_entries, types
+
+
+def CheckIRBinaryCompatibility(input_api, output_api):
+ """Checks for changes to ir.proto that may cause compatibility issues"""
+ proto_file = None
+ old_entries, old_types = {}, []
+ new_entries, new_types = {}, []
+ for file in input_api.AffectedFiles(
+ include_deletes=False,
+ file_filter=lambda f: f.LocalPath().replace(
+ '\\', '/') == "src/tint/utils/protos/ir/ir.proto"):
+ if proto_file:
+ return [
+ output_api.PresubmitError(
+ f"Unexpectedly found more than one ir.proto in change, [{file.AbsoluteLocalPath()}, {proto_file}]"
+ )
+ ]
+ proto_file = file.AbsoluteLocalPath()
+ old_entries, old_types = _CalculateEnumeratedEntriesAndTypes(
+ file.OldContents())
+ new_entries, new_types = _CalculateEnumeratedEntriesAndTypes(
+ file.NewContents())
+
+ changes = []
+ for k in old_entries:
+ if k not in new_entries:
+ changes.append(
+ f"entry '{k}' has been removed, old={old_entries[k]}")
+ continue
+ if old_entries[k] != new_entries[k]:
+ changes.append(
+ f"entry '{k}' has changed, old={old_entries[k]}, new={new_entries[k]}"
+ )
+ continue
+
+ for s in old_types:
+ if s not in new_types:
+ changes.append(f"type '{s}' has been removed")
+
+ if changes:
+ return [
+ output_api.PresubmitError(
+ "Incompatible changes detected in ir.proto", items=changes)
+ ]
+ return []
+
+
def CheckNoStaleGen(input_api, output_api):
"""Checks that Tint generated files are not stale."""
results = []
