f remove xonly_pubkey_to_pubkey

Author: jonasnick

include/secp256k1.h

@@ -801,29 +801,6 @@ SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_from_pubke
     const secp256k1_pubkey *pubkey
 ) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(4);
 
-/** Convert a secp256k1_xonly_pubkey into a secp256k1_pubkey. If this
- *  function is used to invert secp256k1_xonly_pubkey_from_pubkey, the
- *  sign bit must be set to the output of that function. If the sign bit
- *  is 0 the output pubkey encodes a positive point (has a Y coordinate that is
- *  square), otherwise it is negative.
- *
- *  Returns: 1 if the public key was successfully converted
- *           0 otherwise
- *
- *  Args:           ctx: pointer to a context object
- *  Out:         pubkey: pointer to a public key object for placing the
- *                       converted public key (cannot be NULL)
- *  In: xonly_pubkey: pointer to an x-only public key that is converted
- *                    (cannot be NULL)
- *                 sign: sign bit of the resulting public key (can be NULL)
- */
-SECP256K1_API SECP256K1_WARN_UNUSED_RESULT int secp256k1_xonly_pubkey_to_pubkey(
-    const secp256k1_context* ctx,
-    secp256k1_pubkey *pubkey,
-    const secp256k1_xonly_pubkey *xonly_pubkey,
-    int sign
-) SECP256K1_ARG_NONNULL(1) SECP256K1_ARG_NONNULL(2) SECP256K1_ARG_NONNULL(3);
-
 /** Tweak the private key of an x-only pubkey by adding a tweak to it. The public
  *  key of the resulting private key will be the same as the output of
  *  secp256k1_xonly_pubkey_tweak_add called with the same tweak and corresponding

src/secp256k1.c

@@ -803,18 +803,6 @@ int secp256k1_xonly_pubkey_from_pubkey(const secp256k1_context* ctx, secp256k1_x
     return 1;
 }
 
-int secp256k1_xonly_pubkey_to_pubkey(const secp256k1_context* ctx, secp256k1_pubkey *pubkey, const secp256k1_xonly_pubkey *xonly_pubkey, int sign) {
-    VERIFY_CHECK(ctx != NULL);
-    ARG_CHECK(pubkey != NULL);
-    ARG_CHECK(xonly_pubkey != NULL);
-
-    *pubkey = *(const secp256k1_pubkey *) xonly_pubkey;
-    if (sign) {
-        return secp256k1_ec_pubkey_negate(ctx, pubkey);
-    }
-    return 1;
-}
-
 int secp256k1_xonly_privkey_tweak_add(const secp256k1_context* ctx, unsigned char *seckey32, const unsigned char *tweak32) {
     secp256k1_ge ge;
     secp256k1_pubkey pubkey;

src/tests.c

@@ -4273,7 +4273,6 @@ void test_xonly_pubkey(void) {
     unsigned char ones32[32];
     unsigned char zeros64[64] = { 0 };
     secp256k1_pubkey xy_pk;
-    secp256k1_pubkey xy_pk_tmp;
     secp256k1_xonly_pubkey xonly_pk;
     secp256k1_xonly_pubkey xonly_pk_tmp;
     secp256k1_ge pk1;
@@ -4297,12 +4296,10 @@ void test_xonly_pubkey(void) {
     secp256k1_fe_negate(&y, &pk2.y, 1);
     CHECK(secp256k1_fe_equal(&pk1.y, &y) == 1);
 
-    /* Check from_pubkey and to_pubkey */
+    /* Test from_pubkey */
     CHECK(secp256k1_xonly_pubkey_from_pubkey(ctx, &xonly_pk_tmp, &sign, &xy_pk) == 1);
     CHECK(memcmp(&xonly_pk_tmp, &xonly_pk, sizeof(xonly_pk)) == 0);
     CHECK(sign == 1);
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(ctx, &xy_pk_tmp, &xonly_pk, sign) == 1);
-    CHECK(memcmp(&xy_pk_tmp, &xy_pk, sizeof(xy_pk)) == 0);
 
     /* Serialization and parse roundtrip */
     CHECK(secp256k1_xonly_pubkey_create(ctx, &xonly_pk, sk) == 1);
@@ -4421,15 +4418,6 @@ void test_xonly_pubkey_api(void) {
     CHECK(secp256k1_xonly_pubkey_from_pubkey(none, &pk, &pk_is_positive, NULL) == 0);
     CHECK(ecount == 2);
 
-    ecount = 0;
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(none, &xy_pk, &pk, pk_is_positive) == 1);
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(sign, &xy_pk, &pk, pk_is_positive) == 1);
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(vrfy, &xy_pk, &pk, pk_is_positive) == 1);
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(none, NULL, &pk, pk_is_positive) == 0);
-    CHECK(ecount == 1);
-    CHECK(secp256k1_xonly_pubkey_to_pubkey(none, &xy_pk, NULL, pk_is_positive) == 0);
-    CHECK(ecount == 2);
-
     secp256k1_context_destroy(none);
     secp256k1_context_destroy(sign);
     secp256k1_context_destroy(vrfy);