Deprecate UiTokenAmount::ui_amount (bp #15616) (#15651)

* Deprecate UiTokenAmount::ui_amount (#15616)

* Add TokenAmount::ui_amount_string

* Fixup solana-tokens

* Update docs

(cherry picked from commit 19ac79b5cc)

# Conflicts:
#	storage-proto/proto/solana.storage.confirmed_block.rs

* Fix conflicts

Co-authored-by: Tyera Eulberg <teulberg@gmail.com>
Co-authored-by: Tyera Eulberg <tyera@solana.com>

storage-proto/proto/solana.storage.confirmed_block.rs

@@ -104,6 +104,8 @@ pub struct UiTokenAmount {
     pub decimals: u32,
     #[prost(string, tag = "3")]
     pub amount: std::string::String,
+    #[prost(string, tag = "4")]
+    pub ui_amount_string: std::string::String,
 }
 #[derive(Clone, PartialEq, ::prost::Message)]
 pub struct Reward {

storage-proto/src/confirmed_block.proto

@@ -70,6 +70,7 @@ message UiTokenAmount {
     double ui_amount = 1;
     uint32 decimals = 2;
     string amount = 3;
+    string ui_amount_string = 4;
 }
 
 enum RewardType {

storage-proto/src/convert.rs

@@ -1,5 +1,5 @@
 use crate::StoredExtendedRewards;
-use solana_account_decoder::parse_token::UiTokenAmount;
+use solana_account_decoder::parse_token::{real_number_string_trimmed, UiTokenAmount};
 use solana_sdk::{
     hash::Hash,
     instruction::CompiledInstruction,
@@ -14,7 +14,10 @@ use solana_transaction_status::{
     ConfirmedBlock, InnerInstructions, Reward, RewardType, TransactionByAddrInfo,
     TransactionStatusMeta, TransactionTokenBalance, TransactionWithStatusMeta,
 };
-use std::convert::{TryFrom, TryInto};
+use std::{
+    convert::{TryFrom, TryInto},
+    str::FromStr,
+};
 
 pub mod generated {
     include!(concat!(
@@ -383,9 +386,10 @@ impl From<TransactionTokenBalance> for generated::TokenBalance {
             account_index: value.account_index as u32,
             mint: value.mint,
             ui_token_amount: Some(generated::UiTokenAmount {
-                ui_amount: value.ui_token_amount.ui_amount,
+                ui_amount: value.ui_token_amount.ui_amount.unwrap_or_default(),
                 decimals: value.ui_token_amount.decimals as u32,
                 amount: value.ui_token_amount.amount,
+                ui_amount_string: value.ui_token_amount.ui_amount_string,
             }),
         }
     }
@@ -398,9 +402,21 @@ impl From<generated::TokenBalance> for TransactionTokenBalance {
             account_index: value.account_index as u8,
             mint: value.mint,
             ui_token_amount: UiTokenAmount {
-                ui_amount: ui_token_amount.ui_amount,
+                ui_amount: if (ui_token_amount.ui_amount - f64::default()).abs() > f64::EPSILON {
+                    Some(ui_token_amount.ui_amount)
+                } else {
+                    None
+                },
                 decimals: ui_token_amount.decimals as u8,
-                amount: ui_token_amount.amount,
+                amount: ui_token_amount.amount.clone(),
+                ui_amount_string: if !ui_token_amount.ui_amount_string.is_empty() {
+                    ui_token_amount.ui_amount_string
+                } else {
+                    real_number_string_trimmed(
+                        u64::from_str(&ui_token_amount.amount).unwrap_or_default(),
+                        ui_token_amount.decimals as u8,
+                    )
+                },
             },
         }
     }