Cairo: Add ERC20FlashMint extension

.changeset/erc20-flash-mint.md

@@ -0,0 +1,5 @@
+---
+'@openzeppelin/wizard-common': patch
+---
+
+Cairo: Add ERC20FlashMint extension and AI descriptions for ERC20 token kind.

.github/workflows/compile-cairo-alpha-project.yml

@@ -56,6 +56,7 @@ jobs:
           declare -a all_access_options=("disabled" "ownable" "roles" "roles-dar-default" "roles-dar-custom")
           declare -a all_upgradeable_options=("true" "false")
           declare -a all_royalty_options=("disabled" "enabled-default" "enabled-custom")
+          declare -a all_flashmint_options=("disabled" "enabled-default" "enabled-percent-fee" "enabled-custom-fee")
 
           kind="$KIND"
 
@@ -78,18 +79,38 @@ jobs:
                 done
               done
 
-            elif [[ "$kind" == "ERC20" || "$kind" == "ERC6909" || "$kind" == "Custom" ]]; then
+            elif [[ "$kind" == "ERC20" ]]; then
               for access_option in "${all_access_options[@]}"; do
-                proj_name="'$kind, macros: $macros_option, access: $access_option' test project"
-                echo "Generating $proj_name..."
-                yarn run update_scarb_project --kind=$kind --macros=$macros_option --access=$access_option
+                for upgradeable_option in "${all_upgradeable_options[@]}"; do
+                  for flashmint_option in "${all_flashmint_options[@]}"; do
+                    proj_name="'$kind, macros: $macros_option, access: $access_option, upgradeable: $upgradeable_option, flashmint: $flashmint_option' test project"
+                    echo "Generating $proj_name..."
+                    yarn run update_scarb_project --kind=$kind --macros=$macros_option --access=$access_option --upgradeable=$upgradeable_option --flashmint=$flashmint_option
+
+                    echo "Compiling $proj_name..."
+                    scarb clean
+                    scarb build
+
+                    echo "✅ Compiled $proj_name!"
+                    echo "---------------------------------"
+                  done
+                done
+              done
 
-                echo "Compiling $proj_name..."
-                scarb clean
-                scarb build
+            elif [[ "$kind" == "ERC6909" || "$kind" == "Custom" ]]; then
+              for access_option in "${all_access_options[@]}"; do
+                for upgradeable_option in "${all_upgradeable_options[@]}"; do
+                  proj_name="'$kind, macros: $macros_option, access: $access_option, upgradeable: $upgradeable_option' test project"
+                  echo "Generating $proj_name..."
+                  yarn run update_scarb_project --kind=$kind --macros=$macros_option --access=$access_option --upgradeable=$upgradeable_option
 
-                echo "✅ Compiled $proj_name!"
-                echo "---------------------------------"
+                  echo "Compiling $proj_name..."
+                  scarb clean
+                  scarb build
+
+                  echo "✅ Compiled $proj_name!"
+                  echo "---------------------------------"
+                done
               done
 
             else

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

@@ -55,6 +55,18 @@ export const cairoERC20Descriptions = {
   wrapper: 'Whether to include ERC20Wrapper functionality for depositing and withdrawing an underlying token.',
   votes:
     "Whether to keep track of historical balances for voting in on-chain governance, with a way to delegate one's voting power to a trusted account.",
+  flashmint:
+    'Configuration object for the ERC20FlashMint extension (ERC-3156 flash loans). The extension is included only when `enabled` is true; the other fields tune the loan limit, fee, and fee destination.',
+  flashMintEnabled:
+    'Whether to include ERC20FlashMint functionality, allowing flash loans of tokens compliant with ERC-3156.',
+  flashMintMaxAmount:
+    'Maximum amount of tokens that can be flash-loaned in a single call. Use the literal string "max" to inherit the default (the maximum representable u256 minus the current total supply), or a non-negative number in the token\'s decimal units to set a custom cap. A value of 0 effectively disables flash loans without removing the extension.',
+  flashMintFeeMode:
+    "Mode for the flash loan fee. 'percent' charges a percentage of the loaned amount (value provided via feePercent). 'custom' emits a TODO stub for the caller to implement.",
+  flashMintFeePercent:
+    'Percentage of the loan amount charged as the flash loan fee. Number between 0 and 100, fractional values supported (e.g. "0.0013725"). Used when feeMode is \'percent\'. Defaults to 0 (no fee).',
+  flashMintFeeDestination:
+    "Where the flash loan fee is sent. 'burn' sends it to the zero address (effectively burning it). 'fee_receiver' adds a constructor argument that the deployer must populate with a non-zero address; the address is stored on-chain and validated at deploy time.",
 };
 
 export const cairoERC721Descriptions = {

packages/core/cairo_alpha/CHANGELOG.md

@@ -11,6 +11,7 @@
 - Add ERC721URIStorage extension ([#772](https://github.com/OpenZeppelin/contracts-wizard/pull/772))
 - Add ERC721Wrapper extension ([#764](https://github.com/OpenZeppelin/contracts-wizard/pull/764))
 - Add ERC20Wrapper extension ([#763](https://github.com/OpenZeppelin/contracts-wizard/pull/763))
+- Add ERC20FlashMint extension ([#801](https://github.com/OpenZeppelin/contracts-wizard/pull/801))
 
 - **Breaking changes**:
   - Use OpenZeppelin Contracts for Cairo v4.0.0-alpha.0.

packages/core/cairo_alpha/src/contract.ts

@@ -15,6 +15,12 @@ export interface Contract {
   upgradeable: boolean;
   implementedTraits: ImplementedTrait[];
   superVariables: Variable[];
+  storageMembers: StorageMember[];
+}
+
+export interface StorageMember {
+  name: string;
+  type: string;
 }
 
 export type Value = string | number | bigint | { lit: string } | { note: string; value: Value };
@@ -118,6 +124,7 @@ export class ContractBuilder implements Contract {
   private constantsMap: Map<string, Variable> = new Map();
   private useClausesMap: Map<string, UseClause> = new Map();
   private interfaceFlagsSet: Set<string> = new Set();
+  private storageMembersMap: Map<string, StorageMember> = new Map();
 
   constructor(name: string, macros: MacrosOptions, account: boolean = false) {
     this.name = toIdentifier(name, true);
@@ -145,6 +152,24 @@ export class ContractBuilder implements Contract {
     return [...this.useClausesMap.values()];
   }
 
+  get storageMembers(): StorageMember[] {
+    return [...this.storageMembersMap.values()];
+  }
+
+  addStorageMember(member: StorageMember): boolean {
+    const existing = this.storageMembersMap.get(member.name);
+    if (existing !== undefined) {
+      if (existing.type !== member.type) {
+        throw new Error(
+          `Tried to add duplicate storage member ${member.name} with different type: ${member.type} instead of ${existing.type}.`,
+        );
+      }
+      return false;
+    }
+    this.storageMembersMap.set(member.name, member);
+    return true;
+  }
+
   /**
    * Custom flags to denote that the contract implements a specific interface, e.g. ISRC5, to avoid duplicates
    **/