Add optional decimals to Solidity ERC20/Stablecoin/RWA, Confidential ERC7984, and Stellar Fungible/Stablecoin (#812)

Author: ericglau

.changeset/decimals-confidential.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/wizard-confidential': patch
+---
+
+Add optional `decimals` to `erc7984`, which overrides `decimals()` when set to a non-default value. Defaults to 6 as before, with a maximum of 10 since confidential token amounts are represented as uint64. Incompatible with `wrappable`, which derives its decimals from the underlying token (capped at 6).

.changeset/decimals-schemas-mcp.md

@@ -0,0 +1,7 @@
+---
+'@openzeppelin/wizard-common': patch
+'@openzeppelin/contracts-mcp': patch
+'@openzeppelin/contracts-cli': patch
+---
+
+Add `decimals` to the AI schemas, MCP tools, and CLI for Solidity `erc20`, `stablecoin`, `realWorldAsset`, Confidential `erc7984`, and Stellar `fungible`, `stablecoin`.

.changeset/decimals-solidity.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/wizard': patch
+---
+
+Add optional `decimals` to `erc20`, `stablecoin`, and `realWorldAsset`, which overrides `decimals()` when set to a non-default value. Defaults to 18 as before.

.changeset/decimals-stellar.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/wizard-stellar': patch
+---
+
+Add optional `decimals` to `fungible` and `stablecoin`, which sets the token's metadata decimals. Defaults to 7 as before.

packages/cli/src/cli.test.ts.md

@@ -43,6 +43,7 @@ Generated by [AVA](https://avajs.dev).
       --symbol <string>                     The short symbol for the token␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 18.␊
       --burnable                            Whether token holders will be able to destroy their tokens␊
       --pausable                            Whether privileged accounts will be able to pause specifically marked functionality. Useful for emergency response.␊
       --premint <string>                    The number of tokens to premint for the deployer.␊
@@ -120,6 +121,7 @@ Generated by [AVA](https://avajs.dev).
       --symbol <string>                     The short symbol for the token␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 18.␊
       --burnable                            Whether token holders will be able to destroy their tokens␊
       --pausable                            Whether privileged accounts will be able to pause specifically marked functionality. Useful for emergency response.␊
       --premint <string>                    The number of tokens to premint for the deployer.␊
@@ -150,6 +152,7 @@ Generated by [AVA](https://avajs.dev).
       --symbol <string>                     The short symbol for the token␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 18.␊
       --burnable                            Whether token holders will be able to destroy their tokens␊
       --pausable                            Whether privileged accounts will be able to pause specifically marked functionality. Useful for emergency response.␊
       --premint <string>                    The number of tokens to premint for the deployer.␊
@@ -449,6 +452,7 @@ Generated by [AVA](https://avajs.dev).
       --symbol <string>                     The short symbol for the token␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 7.␊
       --burnable                            Whether token holders will be able to destroy their tokens␊
       --votes                               Whether to enable vote checkpoints and delegation for governance.␊
       --pausable                            Whether privileged accounts will be able to pause specifically marked functionality. Useful for emergency response.␊
@@ -495,6 +499,7 @@ Generated by [AVA](https://avajs.dev).
       --symbol <string>                     The short symbol for the token␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 7.␊
       --burnable                            Whether token holders will be able to destroy their tokens␊
       --votes                               Whether to enable vote checkpoints and delegation for governance.␊
       --pausable                            Whether privileged accounts will be able to pause specifically marked functionality. Useful for emergency response.␊
@@ -596,8 +601,9 @@ Generated by [AVA](https://avajs.dev).
       --networkConfig <zama-ethereum>       Specify the provider and network configuration to use for FHEVM contracts.␊
     ␊
     Options:␊
+      --decimals <string>                   The number of decimals used to represent token amounts. Defaults to 6, with a maximum of 10, since confidential token amounts are represented as uint64 and higher decimals would make the maximum total supply too limited. Incompatible with wrappable, which derives its decimals from the underlying token (capped at 6).␊
       --premint <string>                    The number of tokens to premint for the deployer. Cannot be used with wrappable, since preminted tokens would not be backed by the underlying token.␊
-      --wrappable                           Whether to allow wrapping an ERC20 token into a confidential fungible token. Cannot be used with premint, since preminted tokens would not be backed by the underlying token.␊
+      --wrappable                           Whether to allow wrapping an ERC20 token into a confidential fungible token. Derives its decimals from the underlying token (capped at 6), so it cannot be used with custom decimals. Cannot be used with premint, since preminted tokens would not be backed by the underlying token.␊
       --votes <blocknumber|timestamp>       Whether to keep track of historical balances for voting in on-chain governance. Voting durations must be expressed as block numbers or timestamps.␊
       --info.securityContact <string>       Email where people can contact you to report security issues. Will only be visible if contract source code is verified.␊
       --info.license <string>               The license used by the contract, default is "MIT"␊

packages/cli/src/cli.test.ts.snap

@@ -9,11 +9,13 @@ export const confidentialPrompts = {
 export const confidentialERC7984Descriptions = {
   contractURI:
     'The metadata URI for the token. Should follow the schema defined in [ERC-7572](https://eips.ethereum.org/EIPS/eip-7572).',
+  decimals:
+    'The number of decimals used to represent token amounts. Defaults to 6, with a maximum of 10, since confidential token amounts are represented as uint64 and higher decimals would make the maximum total supply too limited. Incompatible with wrappable, which derives its decimals from the underlying token (capped at 6).',
   premint:
     'The number of tokens to premint for the deployer. Cannot be used with wrappable, since preminted tokens would not be backed by the underlying token.',
   networkConfig: 'Specify the provider and network configuration to use for FHEVM contracts.',
   wrappable:
-    'Whether to allow wrapping an ERC20 token into a confidential fungible token. Cannot be used with premint, since preminted tokens would not be backed by the underlying token.',
+    'Whether to allow wrapping an ERC20 token into a confidential fungible token. Derives its decimals from the underlying token (capped at 6), so it cannot be used with custom decimals. Cannot be used with premint, since preminted tokens would not be backed by the underlying token.',
   votes:
     'Whether to keep track of historical balances for voting in on-chain governance. Voting durations must be expressed as block numbers or timestamps.',
 };

packages/common/src/ai/descriptions/confidential.ts

@@ -23,6 +23,7 @@ export const solidityCommonDescriptions = {
 };
 
 export const solidityERC20Descriptions = {
+  decimals: 'The number of decimals used to represent token amounts. Defaults to 18.',
   premint: 'The number of tokens to premint for the deployer.',
   permit:
     'Whether without paying gas, token holders will be able to allow third parties to transfer from their account.',

packages/common/src/ai/descriptions/solidity.ts

@@ -18,6 +18,7 @@ export const stellarCommonDescriptions = {
 };
 
 export const stellarFungibleDescriptions = {
+  decimals: 'The number of decimals used to represent token amounts. Defaults to 7.',
   premint: 'The number of tokens to premint for the deployer.',
   votes: 'Whether to enable vote checkpoints and delegation for governance.',
 };
@@ -32,6 +33,7 @@ export const stellarNonFungibleDescriptions = {
 
 export const stellarStablecoinDescriptions = {
   limitations: 'Whether to restrict certain users from transferring tokens, either via allowing or blocking them.',
+  decimals: 'The number of decimals used to represent token amounts. Defaults to 7.',
   premint: 'The number of tokens to premint for the deployer.',
   votes: 'Whether to enable vote checkpoints and delegation for governance.',
 };

packages/common/src/ai/descriptions/stellar.ts

@@ -15,6 +15,7 @@ export const confidentialERC7984Schema = {
   name: z.string().describe(commonDescriptions.name),
   symbol: z.string().describe(commonDescriptions.symbol),
   contractURI: z.string().describe(confidentialERC7984Descriptions.contractURI),
+  decimals: z.string().optional().describe(confidentialERC7984Descriptions.decimals),
   premint: z.string().optional().describe(confidentialERC7984Descriptions.premint),
   networkConfig: z.literal('zama-ethereum').describe(confidentialERC7984Descriptions.networkConfig),
   wrappable: z.boolean().optional().describe(confidentialERC7984Descriptions.wrappable),