wallet: unit test for duplicate detection in wallet_save_chain_mvt.

diff --git a/wallet/Makefile b/wallet/Makefile
index b79ce3c6..708ebf46 100644
--- a/wallet/Makefile
+++ b/wallet/Makefile
@@ -37,6 +37,7 @@ WALLET_SQL_FILES := 			\
 	wallet/wallet.c 		\
 	wallet/test/run-db.c		\
 	wallet/test/run-wallet.c	\
+	wallet/test/run-chain_moves_duplicate-detect.c	\
 
 wallet/statements_gettextgen.po: $(WALLET_SQL_FILES) $(FORCE)
 	@if $(call SHA256STAMP_CHANGED); then \
diff --git a/wallet/test/run-chain_moves_duplicate-detect.c b/wallet/test/run-chain_moves_duplicate-detect.c
new file mode 100644
index 00000000..fdf62145
--- /dev/null
+++ b/wallet/test/run-chain_moves_duplicate-detect.c
@@ -0,0 +1,538 @@
+#include "config.h"
+
+#include <common/setup.h>
+#include <common/status_levels.h>
+#include <common/utils.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#include "lightningd/log.h"
+
+struct node_id;
+
+static void db_log_(struct logger *log UNUSED, enum log_level level UNUSED, const struct node_id *node_id UNUSED, bool call_notifier UNUSED, const char *fmt UNUSED, ...)
+{
+}
+#define log_ db_log_
+
+#include "wallet/wallet.c"
+
+#include "db/bindings.c"
+#include "db/db_sqlite3.c"
+#include "db/exec.c"
+#include "db/utils.c"
+#include "wallet/db.c"
+#include "common/coin_mvt.c"
+
+/* AUTOGENERATED MOCKS START */
+/* Generated stub for bip32_pubkey */
+void bip32_pubkey(struct lightningd *ld UNNEEDED, struct pubkey *pubkey UNNEEDED, u32 index UNNEEDED)
+{ fprintf(stderr, "bip32_pubkey called!\n"); abort(); }
+/* Generated stub for bitcoind_getrawblockbyheight_ */
+void bitcoind_getrawblockbyheight_(const tal_t *ctx UNNEEDED,
+				   struct bitcoind *bitcoind UNNEEDED,
+				   u32 height UNNEEDED,
+				   void (*cb)(struct bitcoind *bitcoind_ UNNEEDED,
+					      u32 height_ UNNEEDED,
+					      struct bitcoin_blkid *blkid UNNEEDED,
+					      struct bitcoin_block *blk UNNEEDED,
+					      void *arg) UNNEEDED,
+				   void *arg UNNEEDED)
+{ fprintf(stderr, "bitcoind_getrawblockbyheight_ called!\n"); abort(); }
+/* Generated stub for channel_by_dbid */
+struct channel *channel_by_dbid(struct lightningd *ld UNNEEDED, const u64 dbid UNNEEDED)
+{ fprintf(stderr, "channel_by_dbid called!\n"); abort(); }
+/* Generated stub for channel_gossip_get_remote_update */
+const struct peer_update *channel_gossip_get_remote_update(const struct channel *channel UNNEEDED)
+{ fprintf(stderr, "channel_gossip_get_remote_update called!\n"); abort(); }
+/* Generated stub for channel_gossip_update */
+void channel_gossip_update(struct channel *channel UNNEEDED)
+{ fprintf(stderr, "channel_gossip_update called!\n"); abort(); }
+/* Generated stub for channel_mvt_index_created */
+u64 channel_mvt_index_created(struct lightningd *ld UNNEEDED,
+			      struct db *db UNNEEDED,
+			      const struct mvt_account_id *account UNNEEDED,
+			      struct amount_msat credit UNNEEDED,
+			      struct amount_msat debit UNNEEDED)
+{ fprintf(stderr, "channel_mvt_index_created called!\n"); abort(); }
+/* Generated stub for channel_scid_or_local_alias */
+struct short_channel_id channel_scid_or_local_alias(const struct channel *chan UNNEEDED)
+{ fprintf(stderr, "channel_scid_or_local_alias called!\n"); abort(); }
+/* Generated stub for channel_state_name */
+const char *channel_state_name(const struct channel *channel UNNEEDED)
+{ fprintf(stderr, "channel_state_name called!\n"); abort(); }
+/* Generated stub for connect_htlc_in */
+void connect_htlc_in(struct htlc_in_map *map UNNEEDED, struct htlc_in *hin UNNEEDED)
+{ fprintf(stderr, "connect_htlc_in called!\n"); abort(); }
+/* Generated stub for connect_htlc_out */
+void connect_htlc_out(struct htlc_out_map *map UNNEEDED, struct htlc_out *hout UNNEEDED)
+{ fprintf(stderr, "connect_htlc_out called!\n"); abort(); }
+/* Generated stub for create_onionreply */
+struct onionreply *create_onionreply(const tal_t *ctx UNNEEDED,
+				     const struct secret *shared_secret UNNEEDED,
+				     const u8 *failure_msg UNNEEDED)
+{ fprintf(stderr, "create_onionreply called!\n"); abort(); }
+/* Generated stub for fatal */
+void   fatal(const char *fmt UNNEEDED, ...)
+{ fprintf(stderr, "fatal called!\n"); abort(); }
+/* Generated stub for fatal_vfmt */
+void  fatal_vfmt(const char *fmt UNNEEDED, va_list ap UNNEEDED)
+{ fprintf(stderr, "fatal_vfmt called!\n"); abort(); }
+/* Generated stub for find_peer_by_dbid */
+struct peer *find_peer_by_dbid(struct lightningd *ld UNNEEDED, u64 dbid UNNEEDED)
+{ fprintf(stderr, "find_peer_by_dbid called!\n"); abort(); }
+/* Generated stub for forward_index_created */
+u64 forward_index_created(struct lightningd *ld UNNEEDED,
+			  enum forward_status status UNNEEDED,
+			  struct short_channel_id in_channel UNNEEDED,
+			  u64 in_htlc_id UNNEEDED,
+			  struct amount_msat in_amount UNNEEDED,
+			  const struct short_channel_id *out_channel UNNEEDED)
+{ fprintf(stderr, "forward_index_created called!\n"); abort(); }
+/* Generated stub for forward_index_deleted */
+void forward_index_deleted(struct lightningd *ld UNNEEDED,
+			   enum forward_status status UNNEEDED,
+			   struct short_channel_id in_channel UNNEEDED,
+			   u64 in_htlc_id UNNEEDED,
+			   const struct amount_msat *in_amount UNNEEDED,
+			   const struct short_channel_id *out_channel UNNEEDED)
+{ fprintf(stderr, "forward_index_deleted called!\n"); abort(); }
+/* Generated stub for forward_index_update_status */
+u64 forward_index_update_status(struct lightningd *ld UNNEEDED,
+				enum forward_status status UNNEEDED,
+				struct short_channel_id in_channel UNNEEDED,
+				u64 in_htlc_id UNNEEDED,
+				struct amount_msat in_amount UNNEEDED,
+				const struct short_channel_id *out_channel UNNEEDED)
+{ fprintf(stderr, "forward_index_update_status called!\n"); abort(); }
+/* Generated stub for fromwire_hsmd_get_channel_basepoints_reply */
+bool fromwire_hsmd_get_channel_basepoints_reply(const void *p UNNEEDED, struct basepoints *basepoints UNNEEDED, struct pubkey *funding_pubkey UNNEEDED)
+{ fprintf(stderr, "fromwire_hsmd_get_channel_basepoints_reply called!\n"); abort(); }
+/* Generated stub for fromwire_hsmd_get_output_scriptpubkey_reply */
+bool fromwire_hsmd_get_output_scriptpubkey_reply(const tal_t *ctx UNNEEDED, const void *p UNNEEDED, u8 **script UNNEEDED)
+{ fprintf(stderr, "fromwire_hsmd_get_output_scriptpubkey_reply called!\n"); abort(); }
+/* Generated stub for get_channel_basepoints */
+void get_channel_basepoints(struct lightningd *ld UNNEEDED,
+			    const struct node_id *peer_id UNNEEDED,
+			    const u64 dbid UNNEEDED,
+			    struct basepoints *local_basepoints UNNEEDED,
+			    struct pubkey *local_funding_pubkey UNNEEDED)
+{ fprintf(stderr, "get_channel_basepoints called!\n"); abort(); }
+/* Generated stub for hash_cid */
+size_t hash_cid(const struct channel_id *cid UNNEEDED)
+{ fprintf(stderr, "hash_cid called!\n"); abort(); }
+/* Generated stub for htlc_in_check */
+struct htlc_in *htlc_in_check(const struct htlc_in *hin UNNEEDED, const char *abortstr UNNEEDED)
+{ fprintf(stderr, "htlc_in_check called!\n"); abort(); }
+/* Generated stub for htlc_out_connect_htlc_in */
+void htlc_out_connect_htlc_in(struct htlc_out *hout UNNEEDED, struct htlc_in *hin UNNEEDED)
+{ fprintf(stderr, "htlc_out_connect_htlc_in called!\n"); abort(); }
+/* Generated stub for htlcs_index_created */
+u64 htlcs_index_created(struct lightningd *ld UNNEEDED,
+			u64 htlc_id UNNEEDED,
+			const struct channel *channel UNNEEDED,
+			const struct sha256 *payment_hash UNNEEDED,
+			enum side owner UNNEEDED,
+			u32 expiry UNNEEDED,
+			struct amount_msat amount UNNEEDED,
+			enum htlc_state hstate UNNEEDED)
+{ fprintf(stderr, "htlcs_index_created called!\n"); abort(); }
+/* Generated stub for htlcs_index_deleted */
+void htlcs_index_deleted(struct lightningd *ld UNNEEDED,
+			 const struct channel *channel UNNEEDED,
+			 u64 num_deleted UNNEEDED)
+{ fprintf(stderr, "htlcs_index_deleted called!\n"); abort(); }
+/* Generated stub for htlcs_index_update_status */
+u64 htlcs_index_update_status(struct lightningd *ld UNNEEDED,
+			      u64 htlc_id UNNEEDED,
+			      const struct channel *channel UNNEEDED,
+			      const struct sha256 *payment_hash UNNEEDED,
+			      enum side owner UNNEEDED,
+			      u32 expiry UNNEEDED,
+			      struct amount_msat amount UNNEEDED,
+			      enum htlc_state hstate UNNEEDED)
+{ fprintf(stderr, "htlcs_index_update_status called!\n"); abort(); }
+/* Generated stub for inflight_set_last_tx */
+void inflight_set_last_tx(struct channel_inflight *inflight UNNEEDED,
+		          struct bitcoin_tx *last_tx STEALS UNNEEDED,
+		          const struct bitcoin_signature last_sig UNNEEDED)
+{ fprintf(stderr, "inflight_set_last_tx called!\n"); abort(); }
+/* Generated stub for invoices_new */
+struct invoices *invoices_new(const tal_t *ctx UNNEEDED,
+			      struct wallet *wallet UNNEEDED,
+			      struct timers *timers UNNEEDED)
+{ fprintf(stderr, "invoices_new called!\n"); abort(); }
+/* Generated stub for memleak_scan_outpointfilter */
+void memleak_scan_outpointfilter(struct htable *memtable UNNEEDED,
+				 const struct outpointfilter *opf UNNEEDED)
+{ fprintf(stderr, "memleak_scan_outpointfilter called!\n"); abort(); }
+/* Generated stub for new_channel */
+struct channel *new_channel(struct peer *peer UNNEEDED, u64 dbid UNNEEDED,
+			    /* NULL or stolen */
+			    struct wallet_shachain *their_shachain STEALS UNNEEDED,
+			    enum channel_state state UNNEEDED,
+			    enum side opener UNNEEDED,
+			    /* NULL or stolen */
+			    struct logger *log STEALS UNNEEDED,
+			    const char *transient_billboard TAKES UNNEEDED,
+			    u8 channel_flags UNNEEDED,
+			    bool req_confirmed_ins_local UNNEEDED,
+			    bool req_confirmed_ins_remote UNNEEDED,
+			    const struct channel_config *our_config UNNEEDED,
+			    u32 minimum_depth UNNEEDED,
+			    u64 next_index_local UNNEEDED,
+			    u64 next_index_remote UNNEEDED,
+			    u64 next_htlc_id UNNEEDED,
+			    const struct bitcoin_outpoint *funding UNNEEDED,
+			    struct amount_sat funding_sats UNNEEDED,
+			    struct amount_msat push UNNEEDED,
+			    struct amount_sat our_funds UNNEEDED,
+			    bool remote_channel_ready UNNEEDED,
+			    /* NULL or stolen */
+			    struct short_channel_id *scid TAKES UNNEEDED,
+			    struct short_channel_id *old_scids TAKES UNNEEDED,
+			    struct short_channel_id alias_local UNNEEDED,
+			    struct short_channel_id *alias_remote STEALS UNNEEDED,
+			    struct channel_id *cid UNNEEDED,
+			    struct amount_msat our_msatoshi UNNEEDED,
+			    struct amount_msat msatoshi_to_us_min UNNEEDED,
+			    struct amount_msat msatoshi_to_us_max UNNEEDED,
+			    struct bitcoin_tx *last_tx STEALS UNNEEDED,
+			    const struct bitcoin_signature *last_sig UNNEEDED,
+			    /* NULL or stolen */
+			    const struct bitcoin_signature *last_htlc_sigs STEALS UNNEEDED,
+			    const struct channel_info *channel_info UNNEEDED,
+			    const struct fee_states *fee_states TAKES UNNEEDED,
+			    /* NULL or stolen */
+			    u8 *remote_shutdown_scriptpubkey STEALS UNNEEDED,
+			    const u8 *local_shutdown_scriptpubkey UNNEEDED,
+			    u64 final_key_idx UNNEEDED,
+			    bool last_was_revoke UNNEEDED,
+			    /* NULL or stolen */
+			    struct changed_htlc *last_sent_commit STEALS UNNEEDED,
+			    u32 first_blocknum UNNEEDED,
+			    u32 min_possible_feerate UNNEEDED,
+			    u32 max_possible_feerate UNNEEDED,
+			    const struct basepoints *local_basepoints UNNEEDED,
+			    const struct pubkey *local_funding_pubkey UNNEEDED,
+			    bool has_future_per_commitment_point UNNEEDED,
+			    u32 feerate_base UNNEEDED,
+			    u32 feerate_ppm UNNEEDED,
+			    /* NULL or stolen */
+			    const u8 *remote_upfront_shutdown_script STEALS UNNEEDED,
+			    u64 local_static_remotekey_start UNNEEDED,
+			    u64 remote_static_remotekey_start UNNEEDED,
+			    const struct channel_type *type STEALS UNNEEDED,
+			    enum side closer UNNEEDED,
+			    u32 close_attempt_height UNNEEDED,
+			    enum state_change reason UNNEEDED,
+			    /* NULL or stolen */
+			    const struct bitcoin_outpoint *shutdown_wrong_funding STEALS UNNEEDED,
+			    const struct height_states *height_states TAKES UNNEEDED,
+			    u32 lease_expiry UNNEEDED,
+			    secp256k1_ecdsa_signature *lease_commit_sig STEALS UNNEEDED,
+			    u32 lease_chan_max_msat UNNEEDED,
+			    u16 lease_chan_max_ppt UNNEEDED,
+			    struct amount_msat htlc_minimum_msat UNNEEDED,
+			    struct amount_msat htlc_maximum_msat UNNEEDED,
+			    bool ignore_fee_limits UNNEEDED,
+			    /* NULL or stolen */
+			    struct peer_update *peer_update STEALS UNNEEDED,
+			    u64 last_stable_connection UNNEEDED,
+			    const struct channel_stats *stats UNNEEDED,
+			    struct channel_state_change **state_changes STEALS UNNEEDED)
+{ fprintf(stderr, "new_channel called!\n"); abort(); }
+/* Generated stub for new_channel_state_change */
+struct channel_state_change *new_channel_state_change(const tal_t *ctx UNNEEDED,
+						      struct timeabs timestamp UNNEEDED,
+						      enum channel_state old_state UNNEEDED,
+						      enum channel_state new_state UNNEEDED,
+						      enum state_change cause UNNEEDED,
+						      const char *message TAKES UNNEEDED)
+{ fprintf(stderr, "new_channel_state_change called!\n"); abort(); }
+/* Generated stub for new_inflight */
+struct channel_inflight *new_inflight(struct channel *channel UNNEEDED,
+	     struct pubkey *remote_funding STEALS UNNEEDED,
+	     const struct bitcoin_outpoint *funding_outpoint UNNEEDED,
+	     u32 funding_feerate UNNEEDED,
+	     struct amount_sat funding_sat UNNEEDED,
+	     struct amount_sat our_funds UNNEEDED,
+	     struct wally_psbt *funding_psbt STEALS UNNEEDED,
+	     const u32 lease_expiry UNNEEDED,
+	     const secp256k1_ecdsa_signature *lease_commit_sig UNNEEDED,
+	     const u32 lease_chan_max_msat UNNEEDED,
+	     const u16 lease_chan_max_ppt UNNEEDED,
+	     const u32 lease_blockheight_start UNNEEDED,
+	     const struct amount_msat lease_fee UNNEEDED,
+	     const struct amount_sat lease_amt UNNEEDED,
+	     s64 splice_amnt UNNEEDED,
+	     bool i_am_initiator UNNEEDED,
+	     bool force_sign_first UNNEEDED,
+	     bool i_sent_sigs UNNEEDED)
+{ fprintf(stderr, "new_inflight called!\n"); abort(); }
+/* Generated stub for new_logger */
+struct logger *new_logger(const tal_t *ctx UNNEEDED, struct log_book *record UNNEEDED,
+			  const struct node_id *default_node_id UNNEEDED,
+			  const char *fmt UNNEEDED, ...)
+{ fprintf(stderr, "new_logger called!\n"); abort(); }
+/* Generated stub for new_peer */
+struct peer *new_peer(struct lightningd *ld UNNEEDED, u64 dbid UNNEEDED,
+		      const struct node_id *id UNNEEDED,
+		      const struct wireaddr_internal *addr UNNEEDED,
+		      const struct wireaddr *last_known_addr UNNEEDED,
+		      const u8 *their_features TAKES UNNEEDED,
+		      bool connected_incoming UNNEEDED)
+{ fprintf(stderr, "new_peer called!\n"); abort(); }
+/* Generated stub for notify_channel_mvt */
+void notify_channel_mvt(struct lightningd *ld UNNEEDED,
+			const struct channel_coin_mvt *chan_mvt UNNEEDED,
+			u64 id UNNEEDED)
+{ fprintf(stderr, "notify_channel_mvt called!\n"); abort(); }
+/* Generated stub for notify_forward_event */
+void notify_forward_event(struct lightningd *ld UNNEEDED,
+			  const struct htlc_in *in UNNEEDED,
+			  /* May be NULL if we don't know. */
+			  const struct short_channel_id *scid_out UNNEEDED,
+			  /* May be NULL. */
+			  const struct amount_msat *amount_out UNNEEDED,
+			  enum forward_status state UNNEEDED,
+			  enum onion_wire failcode UNNEEDED,
+			  struct timeabs *resolved_time UNNEEDED,
+			  enum forward_style forward_style UNNEEDED,
+			  u64 created_index UNNEEDED,
+			  u64 updated_index UNNEEDED)
+{ fprintf(stderr, "notify_forward_event called!\n"); abort(); }
+/* Generated stub for onion_wire_name */
+const char *onion_wire_name(int e UNNEEDED)
+{ fprintf(stderr, "onion_wire_name called!\n"); abort(); }
+/* Generated stub for outpointfilter_add */
+void outpointfilter_add(struct outpointfilter *of UNNEEDED,
+			const struct bitcoin_outpoint *outpoint UNNEEDED)
+{ fprintf(stderr, "outpointfilter_add called!\n"); abort(); }
+/* Generated stub for outpointfilter_matches */
+bool outpointfilter_matches(struct outpointfilter *of UNNEEDED,
+			    const struct bitcoin_outpoint *outpoint UNNEEDED)
+{ fprintf(stderr, "outpointfilter_matches called!\n"); abort(); }
+/* Generated stub for outpointfilter_new */
+struct outpointfilter *outpointfilter_new(tal_t *ctx UNNEEDED)
+{ fprintf(stderr, "outpointfilter_new called!\n"); abort(); }
+/* Generated stub for outpointfilter_remove */
+void outpointfilter_remove(struct outpointfilter *of UNNEEDED,
+			   const struct bitcoin_outpoint *outpoint UNNEEDED)
+{ fprintf(stderr, "outpointfilter_remove called!\n"); abort(); }
+/* Generated stub for peer_set_dbid */
+void peer_set_dbid(struct peer *peer UNNEEDED, u64 dbid UNNEEDED)
+{ fprintf(stderr, "peer_set_dbid called!\n"); abort(); }
+/* Generated stub for psbt_fixup */
+const u8 *psbt_fixup(const tal_t *ctx UNNEEDED, const u8 *psbtblob UNNEEDED)
+{ fprintf(stderr, "psbt_fixup called!\n"); abort(); }
+/* Generated stub for remove_htlc_in_by_dbid */
+struct htlc_in *remove_htlc_in_by_dbid(struct htlc_in_map *remaining_htlcs_in UNNEEDED,
+				       u64 dbid UNNEEDED)
+{ fprintf(stderr, "remove_htlc_in_by_dbid called!\n"); abort(); }
+/* Generated stub for rune_unique_id */
+u64 rune_unique_id(const struct rune *rune UNNEEDED)
+{ fprintf(stderr, "rune_unique_id called!\n"); abort(); }
+/* Generated stub for sendpay_index_created */
+u64 sendpay_index_created(struct lightningd *ld UNNEEDED,
+			  const struct sha256 *payment_hash UNNEEDED,
+			  u64 partid UNNEEDED,
+			  u64 groupid UNNEEDED,
+			  enum payment_status status UNNEEDED)
+{ fprintf(stderr, "sendpay_index_created called!\n"); abort(); }
+/* Generated stub for sendpay_index_deleted */
+void sendpay_index_deleted(struct lightningd *ld UNNEEDED,
+			   const struct sha256 *payment_hash UNNEEDED,
+			   u64 partid UNNEEDED,
+			   u64 groupid UNNEEDED,
+			   enum payment_status status UNNEEDED)
+{ fprintf(stderr, "sendpay_index_deleted called!\n"); abort(); }
+/* Generated stub for sendpay_index_update_status */
+u64 sendpay_index_update_status(struct lightningd *ld UNNEEDED,
+				const struct sha256 *payment_hash UNNEEDED,
+				u64 partid UNNEEDED,
+				u64 groupid UNNEEDED,
+				enum payment_status status UNNEEDED)
+{ fprintf(stderr, "sendpay_index_update_status called!\n"); abort(); }
+/* Generated stub for to_canonical_invstr */
+const char *to_canonical_invstr(const tal_t *ctx UNNEEDED, const char *invstring UNNEEDED)
+{ fprintf(stderr, "to_canonical_invstr called!\n"); abort(); }
+/* Generated stub for towire_hsmd_get_channel_basepoints */
+u8 *towire_hsmd_get_channel_basepoints(const tal_t *ctx UNNEEDED, const struct node_id *peerid UNNEEDED, u64 dbid UNNEEDED)
+{ fprintf(stderr, "towire_hsmd_get_channel_basepoints called!\n"); abort(); }
+/* Generated stub for towire_hsmd_get_output_scriptpubkey */
+u8 *towire_hsmd_get_output_scriptpubkey(const tal_t *ctx UNNEEDED, u64 channel_id UNNEEDED, const struct node_id *peer_id UNNEEDED, const struct pubkey *commitment_point UNNEEDED)
+{ fprintf(stderr, "towire_hsmd_get_output_scriptpubkey called!\n"); abort(); }
+/* Generated stub for towire_temporary_node_failure */
+u8 *towire_temporary_node_failure(const tal_t *ctx UNNEEDED)
+{ fprintf(stderr, "towire_temporary_node_failure called!\n"); abort(); }
+/* Generated stub for txfilter_add_scriptpubkey */
+void txfilter_add_scriptpubkey(struct txfilter *filter UNNEEDED, const u8 *script TAKES UNNEEDED)
+{ fprintf(stderr, "txfilter_add_scriptpubkey called!\n"); abort(); }
+/* Generated stub for wait_index_name */
+const char *wait_index_name(enum wait_index index UNNEEDED)
+{ fprintf(stderr, "wait_index_name called!\n"); abort(); }
+/* Generated stub for wait_subsystem_name */
+const char *wait_subsystem_name(enum wait_subsystem subsystem UNNEEDED)
+{ fprintf(stderr, "wait_subsystem_name called!\n"); abort(); }
+/* Generated stub for wire_sync_read */
+u8 *wire_sync_read(const tal_t *ctx UNNEEDED, int fd UNNEEDED)
+{ fprintf(stderr, "wire_sync_read called!\n"); abort(); }
+/* Generated stub for wire_sync_write */
+bool wire_sync_write(int fd UNNEEDED, const void *msg TAKES UNNEEDED)
+{ fprintf(stderr, "wire_sync_write called!\n"); abort(); }
+/* AUTOGENERATED MOCKS END */
+
+void plugin_hook_db_sync(struct db *db UNNEEDED)
+{
+}
+
+void migrate_from_account_db(struct lightningd *ld UNNEEDED, struct db *db UNNEEDED)
+{
+}
+
+u64 chain_mvt_index_created(struct lightningd *ld UNNEEDED,
+			    struct db *db UNNEEDED,
+			    const struct mvt_account_id *account UNNEEDED,
+			    struct amount_msat credit UNNEEDED,
+			    struct amount_msat debit UNNEEDED)
+{
+	static u64 idx = 1;
+	return idx++;
+}
+
+void notify_chain_mvt(struct lightningd *ld UNNEEDED,
+		      const struct chain_coin_mvt *chain_mvt UNNEEDED,
+		      u64 id UNNEEDED)
+{
+}
+
+void logv(struct logger *logger UNNEEDED, enum log_level level UNNEEDED, const struct node_id *node_id UNNEEDED,
+	  bool call_notifier UNNEEDED, const char *fmt UNNEEDED, va_list ap UNNEEDED)
+{
+}
+
+static size_t count_moves(struct db *db)
+{
+	struct db_stmt *stmt;
+	size_t ret;
+
+	stmt = db_prepare_v2(db,
+			     SQL("SELECT COUNT(*)"
+				 " FROM chain_moves"));
+	db_query_prepared(stmt);
+	db_step(stmt);
+
+	ret = db_col_int(stmt, "COUNT(*)");
+	tal_free(stmt);
+	return ret;
+}
+
+int main(int argc, const char *argv[])
+{
+	char *filename;
+	struct wallet *w;
+	struct lightningd *ld;
+	struct chain_coin_mvt *chain_mvt;
+	struct channel_id cid;
+	struct channel *channel;
+	const char *channel_cid_name;
+	struct bitcoin_txid txid, txid2;
+	struct bitcoin_outpoint outpoint, outpoint2;
+	struct db_stmt *stmt;
+
+	common_setup(argv[0]);
+	close(tmpdir_mkstemp(tmpctx, "ldb-XXXXXX", &filename));
+
+	ld = talz(tmpctx, struct lightningd);
+
+	chainparams = chainparams_for_network("bitcoin");
+	ld->wallet_dsn = tal_fmt(ld, "sqlite3://%s", filename);
+	ld->developer = false;
+	ld->wallet = w = tal(ld, struct wallet);
+	ld->wallet->db = db_setup(ld->wallet, ld, NULL);
+
+	memset(&cid, 1, sizeof(cid));
+	memset(&txid, 2, sizeof(txid));
+	txid2 = txid;
+	txid2.shad.sha.u.u8[0] = 0;
+	memset(&outpoint, 3, sizeof(outpoint));
+	outpoint2 = outpoint;
+	outpoint2.n++;
+	channel = tal(ld, struct channel);
+	channel->cid = cid;
+	channel->dbid = 1;
+	channel_cid_name = fmt_channel_id(tmpctx, &cid);
+
+	db_begin_transaction(w->db);
+	stmt = db_prepare_v2(
+		w->db, SQL("INSERT INTO channels ("
+			   "id, full_channel_id"
+			   ") VALUES (?,?);"));
+	db_bind_u64(stmt, channel->dbid);
+	db_bind_channel_id(stmt, &cid);
+	db_exec_prepared_v2(take(stmt));
+
+	chain_mvt = new_coin_channel_close(tmpctx,
+					   NULL,
+					   channel_cid_name,
+					   &txid,
+					   &outpoint,
+					   100,
+					   AMOUNT_MSAT(100000),
+					   AMOUNT_SAT(1000),
+					   5, false);
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 1);
+	/* Exact duplicate: no */
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 1);
+
+	/* Different txid */
+	chain_mvt = new_coin_channel_close(tmpctx,
+					   NULL,
+					   channel_cid_name,
+					   &txid2,
+					   &outpoint,
+					   100,
+					   AMOUNT_MSAT(100000),
+					   AMOUNT_SAT(1000),
+					   5, false);
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 2);
+
+	/* Same one: channel by channel not name. */
+	chain_mvt = new_coin_channel_close(tmpctx,
+					   NULL,
+					   channel_cid_name,
+					   &txid,
+					   &outpoint2,
+					   100,
+					   AMOUNT_MSAT(100000),
+					   AMOUNT_SAT(1000),
+					   5, false);
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 3);
+
+	/* Same one: channel by channel not name. */
+	chain_mvt = new_coin_channel_close(tmpctx,
+					   channel,
+					   NULL,
+					   &txid,
+					   &outpoint,
+					   100,
+					   AMOUNT_MSAT(100000),
+					   AMOUNT_SAT(1000),
+					   5, false);
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 3);
+
+	/* Different tag */
+	chain_mvt->tags = mk_mvt_tags(MVT_DEPOSIT);
+	wallet_save_chain_mvt(ld, chain_mvt);
+	assert(count_moves(w->db) == 4);
+	db_commit_transaction(w->db);
+	unlink(filename);
+	common_shutdown();
+	trace_cleanup();
+}