exp/cmd/apidiff: incorrectly reporting changes

[jeanbza]

Running apidiff against two of the same thing results in changes. This must be impossible, since nothing has changed since apidiff -w and apidiff. This started happening within the last week, IIRC. Here's a repro:

deklerk at deklerk-macbookpro2 in ~/workspace/google-cloud-go/bigquery on rege*
$ cd /tmp
deklerk at deklerk-macbookpro2 in /tmp
$ git clone https://code.googlesource.com/gocloud gocloud1
Cloning into 'gocloud1'...
remote: Sending approximately 25.35 MiB ...
remote: Counting objects: 10, done
remote: Total 28180 (delta 15088), reused 28180 (delta 15088)
Receiving objects: 100% (28180/28180), 25.35 MiB | 8.26 MiB/s, done.
Resolving deltas: 100% (15088/15088), done.
deklerk at deklerk-macbookpro2 in /tmp
$ cd gocloud1/bigquery
deklerk at deklerk-macbookpro2 in /tmp/gocloud1/bigquery on master
$ apidiff -w /tmp/pkg.master cloud.google.com/go/bigquery
deklerk at deklerk-macbookpro2 in /tmp/gocloud1/bigquery on master
$ apidiff /tmp/pkg.master cloud.google.com/go/bigquery
Incompatible changes:
- Reader: removed
Compatible changes:
- AccessEntry: added
- AccessRole: added
- Avro: added
- BatchPriority: added
- Bigtable: added
- BigtableColumn: added
- BigtableColumnFamily: added
- BigtableOptions: added
- BooleanFieldType: added
- BytesFieldType: added
- CSV: added
- CSVOptions: added
- CivilDateTimeString: added
- CivilTimeString: added
- Client: added
- Clustering: added
- Compression: added
- Copier: added
- CopyConfig: added
- CreateIfNeeded: added
- CreateNever: added
- DataFormat: added
- Dataset: added
- DatasetIterator: added
- DatasetMetadata: added
- DatasetMetadataToUpdate: added
- DatastoreBackup: added
- DateFieldType: added
- DateTimeFieldType: added
- DomainEntity: added
- Done: added
- Encoding: added
- EncryptionConfig: added
- EntityType: added
- Error: added
- ExplainQueryStage: added
- ExplainQueryStep: added
- ExternalData: added
- ExternalDataConfig: added
- ExternalDataConfigOptions: added
- ExternalTable: added
- ExtractConfig: added
- ExtractStatistics: added
- Extractor: added
- FieldSchema: added
- FieldType: added
- FileConfig: added
- FloatFieldType: added
- GCSReference: added
- GeographyFieldType: added
- GoogleSheets: added
- GoogleSheetsOptions: added
- GroupEmailEntity: added
- Gzip: added
- ISO_8859_1: added
- InferSchema: added
- Inserter: added
- IntegerFieldType: added
- InteractivePriority: added
- JSON: added
- Job: added
- JobConfig: added
- JobIDConfig: added
- JobIterator: added
- JobStatistics: added
- JobStatus: added
- LoadConfig: added
- LoadSource: added
- LoadStatistics: added
- Loader: added
- Model: added
- ModelIterator: added
- ModelMetadata: added
- ModelMetadataToUpdate: added
- MultiError: added
- NeverExpire: added
- NewClient: added
- NewGCSReference: added
- NewReaderSource: added
- None: added
- NullBool: added
- NullDate: added
- NullDateTime: added
- NullFloat64: added
- NullGeography: added
- NullInt64: added
- NullString: added
- NullTime: added
- NullTimestamp: added
- NumericFieldType: added
- NumericPrecisionDigits: added
- NumericScaleDigits: added
- NumericString: added
- ORC: added
- OwnerRole: added
- Parquet: added
- Pending: added
- PutMultiError: added
- Query: added
- QueryConfig: added
- QueryParameter: added
- QueryPriority: added
- QueryStatistics: added
- QueryTimelineSample: added
- ReaderRole: added
- ReaderSource: added
- RecordFieldType: added
- RegularTable: added
- Routine: added
- RoutineArgument: added
- RoutineIterator: added
- RoutineMetadata: added
- RoutineMetadataToUpdate: added
- RowInsertionError: added
- RowIterator: added
- Running: added
- Schema: added
- SchemaFromJSON: added
- Scope: added
- Seed: added
- SpecialGroupEntity: added
- StandardSQLDataType: added
- StandardSQLField: added
- StandardSQLStructType: added
- State: added
- StateUnspecified: added
- Statistics: added
- StreamingBuffer: added
- StringFieldType: added
- StructSaver: added
- Table: added
- TableCreateDisposition: added
- TableIterator: added
- TableMetadata: added
- TableMetadataToUpdate: added
- TableType: added
- TableWriteDisposition: added
- TimeFieldType: added
- TimePartitioning: added
- TimestampFieldType: added
- TrainingRun: added
- UTF_8: added
- Uploader: added
- UserEmailEntity: added
- Value: added
- ValueLoader: added
- ValueSaver: added
- ValuesSaver: added
- ViewEntity: added
- ViewTable: added
- WriteAppend: added
- WriteEmpty: added
- WriteTruncate: added
- WriterRole: added

[jeanbza]

cc @jba

[jeanbza]

FYI we are using golang.org/x/tools v0.0.0-20191010201905-e5ffc44a6fee. It may be useful to build an apidiff version for easier debugging, as gopls has.

[jba]

Wild. Will take a look.

[jeanbza]

tyvm! FWIW that directory is its own module nested under cloud.google.com/go, so maybe there's some weird multi-module thing going on.

[jba]

Could not reproduce.
First I did:

> git clone https://go.googlesource.com/exp go-exp
> cd go-exp
> go install ./cmd/apidiff

Then I followed what you did. I got no output from the apidiff call. Just to make sure it was looking in the right place, I changed something in bigquery.go and ran it again, and it produced the right output.

[jeanbza]

When I install apidiff the way you did, the errors went away. But, when I use go get -u golang.org/x/tools && go install golang.org/x/exp/cmd/apidiff, I see the error. Here's another repro: https://gist.github.com/jadekler/934ea1fdd5bb6d47e70de0cd389a16ce. And, another repro on a goobuntu machine: https://gist.github.com/jadekler/ef356b1a1dee2a798e2c422ebfd41610.

I wonder if I'm somehow not getting the latest version of apidiff with go get && go install...? Also, it's weird to me that go get -u golang.org/x/exp doesn't result in a golang.org/x/exp entry in my go.mod. Any idea what's up with that?

[gopherbot]

Change https://golang.org/cl/200997 mentions this issue: cmd/apidiff: store package path with export data