feat: fix SavePolicy bug to preserve unique indexes by using DeleteMany instead of Drop

[Copilot]

fix: #72

[CLAassistant]

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[coveralls]

coverage: 82.744%. remained the same
when pulling 34640bb on copilot/fix-savepolicy-unique-index-issue
into 843cf7b on master.

[hsluoyz]

@copilot fix failed CI check:

Run go test -v -coverprofile=./profile.cov ./...
go: downloading github.com/casbin/casbin/v2 v2.71.1
go: downloading go.mongodb.org/mongo-driver/v2 v2.2.1
go: downloading github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible
go: downloading github.com/youmark/pkcs8 v0.0.0-20240726163527-a2c0da244d78
go: downloading github.com/golang/snappy v1.0.0
go: downloading github.com/klauspost/compress v1.16.7
go: downloading github.com/xdg-go/scram v1.1.2
go: downloading github.com/xdg-go/stringprep v1.0.4
go: downloading golang.org/x/crypto v0.33.0
go: downloading golang.org/x/text v0.22.0
go: downloading golang.org/x/sync v0.11.0
go: downloading github.com/xdg-go/pbkdf2 v1.0.0
=== RUN   TestAdapter
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:158: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:176: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:195: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write] [alice data1 write]]
    adapter_test.go:212: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:226: Policy:  [[alice data1 read] [bob data2 write]]
    adapter_test.go:236: Policy:  [[bob data2 write]]
    adapter_test.go:242: Policy:  []
--- PASS: TestAdapter (0.03s)
=== RUN   TestAddPolicies
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:258: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:278: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write] [bob data2 read] [alice data2 write] [alice data2 read] [bob data1 write] [bob data1 read]]
    adapter_test.go:304: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
--- PASS: TestAddPolicies (0.02s)
=== RUN   TestDeleteFilteredAdapter
    adapter_test.go:332: Policy:  [[domain1 alice data3 read accept service1] [domain1 alice data3 write accept service2]]
    adapter_test.go:342: Policy:  [[domain1 alice data3 write accept service2]]
    adapter_test.go:351: Policy:  []
--- PASS: TestDeleteFilteredAdapter (0.01s)
=== RUN   TestFilteredAdapter
    adapter_test.go:377: Policy:  [[bob data2 write]]
    adapter_test.go:385: Policy:  [[alice data1 read] [alice data1 write]]
    adapter_test.go:406: Policy:  [[alice data1 read] [data2_admin data2 read]]
--- PASS: TestFilteredAdapter (0.01s)
=== RUN   TestNewAdapterWithInvalidURL
--- PASS: TestNewAdapterWithInvalidURL (0.00s)
=== RUN   TestNewAdapterWithUnknownURL
--- PASS: TestNewAdapterWithUnknownURL (30.00s)
=== RUN   TestNewAdapterWithDatabase
--- PASS: TestNewAdapterWithDatabase (0.01s)
=== RUN   TestNewAdapterWithClientOption
--- PASS: TestNewAdapterWithClientOption (0.01s)
=== RUN   TestNewAdapterWithCollectionName
--- PASS: TestNewAdapterWithCollectionName (0.01s)
=== RUN   TestNewAdapterByDB
--- PASS: TestNewAdapterByDB (0.00s)
=== RUN   TestUpdatePolicy
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:507: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:525: Policy:  [[alice data1 write] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:535: Policy:  [[alice data1 read] [bob data2 read] [data2_admin data2 read] [data2_admin data2 write]]
--- PASS: TestUpdatePolicy (0.01s)
=== RUN   TestUpdateFilteredPolicies
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:594: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
Warning: 7 05:06:08 [WARNING]: As your mongodb server doesn't allow a replica set, transaction operation is not supported. So Casbin Adapter will run non-transactional updating!
Warning: 7 05:06:08 [WARNING]: As your mongodb server doesn't allow a replica set, transaction operation is not supported. So Casbin Adapter will run non-transactional updating!
--- PASS: TestUpdateFilteredPolicies (0.01s)
=== RUN   TestUpdateFilteredPoliciesTxn
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:624: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
--- PASS: TestUpdateFilteredPoliciesTxn (0.02s)
=== RUN   TestSavePolicyPreservesIndexes
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
--- PASS: TestSavePolicyPreservesIndexes (0.01s)
=== RUN   TestSavePolicyPreventsDuplicates
    adapter_test.go:124: Policy:  []
    adapter_test.go:131: Policy:  [[alice data1 read] [bob data2 write] [data2_admin data2 read] [data2_admin data2 write]]
    adapter_test.go:694: Expected AddPolicy of duplicate to fail due to unique index, but it succeeded
--- FAIL: TestSavePolicyPreventsDuplicates (0.01s)
FAIL
	github.com/casbin/mongodb-adapter/v4	coverage: 85.5% of statements
FAIL	github.com/casbin/mongodb-adapter/v4	30.152s
FAIL
Error: Process completed with exit code 1.

[Copilot]

@copilot fix failed CI check:

...

Fixed in commit 34640bb. The test was calling e.AddPolicy() which performs in-memory duplicate checking before calling the adapter. Changed to call adapter.AddPolicy() directly to test the MongoDB unique index constraint.