fix: resolve Dgraph type name from DType tag in mutation validation

[mlwelles]

Problem

When AutoSchema is disabled, the pre-mutation schema check in client.process derives the type name from the Go struct name (reflect.ValueOf(...).Type().Name()), while schema generation derives it from the DType tag. For a struct whose Dgraph type differs from its Go name, the two disagree and every mutation is rejected:

type migrationLock struct {
    DType []string `json:"dgraph.type,omitempty" dgraph:"MigrationLock"`
    // ...
}

After UpdateSchema registers type MigrationLock, an Insert of this struct fails with:

schema validation failed: database schema does not contain type migrationLock

even though the schema contains type MigrationLock. This breaks any AutoSchema-disabled workflow whose Go struct name differs from its Dgraph type name (for example, schema-migration tooling that keeps its bookkeeping types unexported).

Fix

Resolve the type name in the validation the same way mutations and schema generation already do — via the existing getNodeType helper, which reads the DType value and falls back to the Go struct name. One line, plus a regression test that fails before the change and passes after.

Test

TestMutateValidation_ResolvesDTypeName registers a type whose Dgraph name differs from its Go struct name and asserts the subsequent Insert passes validation with AutoSchema disabled.

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Summary by cubic

Fixes mutation validation to resolve the Dgraph type name from the DType tag (via getNodeType) instead of the Go struct name when AutoSchema is disabled. This prevents false “schema does not contain type …” errors for structs whose Dgraph type differs from their Go name.

• Bug Fixes
  • Use getNodeType in the pre-mutation schema check to read the DType tag and fall back to the struct name.
  • Add regression test TestMutateValidation_ResolvesDTypeName to cover the mismatch case with AutoSchema disabled.

^{Written for commit 0717e38. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 2 files

_{Re-trigger cubic}