attempted to encode a malformed backend state file; state st

Error message

attempted to encode a malformed backend state file; state store type is missing

What it means

A defensive check at statestore_config_state.go:48 that rejects a state store whose Type is the empty string. Note: in the current code this branch is effectively unreachable because Empty() (checked just above at line 45) already returns true when Type == '', so error 767 fires first. It exists to guard against a future change to Empty() semantics.

Source

Thrown at internal/command/workdir/statestore_config_state.go:49

	Hash               uint64                          `json:"hash"`                 // Hash of the state_store block's configuration, including the nested provider block
	ProviderSupplyMode getproviders.ProviderSupplyMode `json:"provider_supply_mode"` // How the provider was supplied to Terraform during the init operation that created this config state.
}

// Empty returns true if there is no active state store.
func (s *StateStoreConfigState) Empty() bool {
	return s == nil || s.Type == ""
}

// Validate returns true if there are no missing expected values, and
// important values have been validated, e.g. FQNs. When the config is
// invalid an error will be returned.
func (s *StateStoreConfigState) Validate() error {
	// Are any bits of data totally missing?
	if s.Empty() {
		return fmt.Errorf("attempted to encode a malformed backend state file; data is empty")
	}
	if s.Type == "" {
		return fmt.Errorf("attempted to encode a malformed backend state file; state store type is missing")
	}
	if s.Provider == nil {
		return fmt.Errorf("attempted to encode a malformed backend state file; provider data is missing")
	}
	if s.ConfigRaw == nil {
		return fmt.Errorf("attempted to encode a malformed backend state file; state_store configuration data is missing")
	}

	// Validity of data that is there
	err := s.Provider.Source.Validate()
	if err != nil {
		return fmt.Errorf("state store is not valid: %w", err)
	}

	// Version information is required if the provider isn't builtin or unmanaged by Terraform
	switch s.ProviderSupplyMode {
	case getproviders.BuiltIn, getproviders.Reattached, getproviders.DevOverride:
		// These modes do not require version information

View on GitHub (pinned to c9def3e214)

Solutions

Treat occurrence as a code bug and report it, since the guards are inconsistent.
Populate Type before constructing/encoding the StateStoreConfigState.
Re-run 'terraform init' to regenerate a well-formed file.

Example fix

// before — dead path in current code; if Empty() ever changed:
s := &StateStoreConfigState{ /* Type missing */ }
// after
s.Type = "remote"

Defensive patterns

Strategy: validation

Validate before calling

// Direct guard mirroring the (currently redundant) check.
if s != nil && s.Type == "" {
    return errors.New("state store type must be set")
}

Type guard

null

Try / catch

null

Prevention

Keep Empty() semantics consistent with the per-field validation checks.
If this branch ever fires, treat it as a divergence bug and add a test pinning the invariant.

When it happens

Trigger: Validate() reaches line 48 with s.Type == '' but s.Empty() returned false — only possible if Empty()'s definition diverges from the individual field checks.

Common situations: Not reachable in shipped code; would indicate Empty() logic and the per-field checks drifted apart (a maintenance bug).

Understand the failure class

Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

AI-assisted analysis of hashicorp/terraform@c9def3e214 (2026-08-07). Data as JSON: /api/errors/796c32a50015a248. Report an issue: GitHub.